Pritikin, Joshua N; Brick, Timothy R; Neale, Michael C
2018-04-01
A novel method for the maximum likelihood estimation of structural equation models (SEM) with both ordinal and continuous indicators is introduced using a flexible multivariate probit model for the ordinal indicators. A full information approach ensures unbiased estimates for data missing at random. Exceeding the capability of prior methods, up to 13 ordinal variables can be included before integration time increases beyond 1 s per row. The method relies on the axiom of conditional probability to split apart the distribution of continuous and ordinal variables. Due to the symmetry of the axiom, two similar methods are available. A simulation study provides evidence that the two similar approaches offer equal accuracy. A further simulation is used to develop a heuristic to automatically select the most computationally efficient approach. Joint ordinal continuous SEM is implemented in OpenMx, free and open-source software.
Simoneau, Gabrielle; Levis, Brooke; Cuijpers, Pim; Ioannidis, John P A; Patten, Scott B; Shrier, Ian; Bombardier, Charles H; de Lima Osório, Flavia; Fann, Jesse R; Gjerdingen, Dwenda; Lamers, Femke; Lotrakul, Manote; Löwe, Bernd; Shaaban, Juwita; Stafford, Lesley; van Weert, Henk C P M; Whooley, Mary A; Wittkampf, Karin A; Yeung, Albert S; Thombs, Brett D; Benedetti, Andrea
2017-11-01
Individual patient data (IPD) meta-analyses are increasingly common in the literature. In the context of estimating the diagnostic accuracy of ordinal or semi-continuous scale tests, sensitivity and specificity are often reported for a given threshold or a small set of thresholds, and a meta-analysis is conducted via a bivariate approach to account for their correlation. When IPD are available, sensitivity and specificity can be pooled for every possible threshold. Our objective was to compare the bivariate approach, which can be applied separately at every threshold, to two multivariate methods: the ordinal multivariate random-effects model and the Poisson correlated gamma-frailty model. Our comparison was empirical, using IPD from 13 studies that evaluated the diagnostic accuracy of the 9-item Patient Health Questionnaire depression screening tool, and included simulations. The empirical comparison showed that the implementation of the two multivariate methods is more laborious in terms of computational time and sensitivity to user-supplied values compared to the bivariate approach. Simulations showed that ignoring the within-study correlation of sensitivity and specificity across thresholds did not worsen inferences with the bivariate approach compared to the Poisson model. The ordinal approach was not suitable for simulations because the model was highly sensitive to user-supplied starting values. We tentatively recommend the bivariate approach rather than more complex multivariate methods for IPD diagnostic accuracy meta-analyses of ordinal scale tests, although the limited type of diagnostic data considered in the simulation study restricts the generalization of our findings. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Non-proportional odds multivariate logistic regression of ordinal family data.
Zaloumis, Sophie G; Scurrah, Katrina J; Harrap, Stephen B; Ellis, Justine A; Gurrin, Lyle C
2015-03-01
Methods to examine whether genetic and/or environmental sources can account for the residual variation in ordinal family data usually assume proportional odds. However, standard software to fit the non-proportional odds model to ordinal family data is limited because the correlation structure of family data is more complex than for other types of clustered data. To perform these analyses we propose the non-proportional odds multivariate logistic regression model and take a simulation-based approach to model fitting using Markov chain Monte Carlo methods, such as partially collapsed Gibbs sampling and the Metropolis algorithm. We applied the proposed methodology to male pattern baldness data from the Victorian Family Heart Study. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Tang, Yongqiang
2018-04-30
The controlled imputation method refers to a class of pattern mixture models that have been commonly used as sensitivity analyses of longitudinal clinical trials with nonignorable dropout in recent years. These pattern mixture models assume that participants in the experimental arm after dropout have similar response profiles to the control participants or have worse outcomes than otherwise similar participants who remain on the experimental treatment. In spite of its popularity, the controlled imputation has not been formally developed for longitudinal binary and ordinal outcomes partially due to the lack of a natural multivariate distribution for such endpoints. In this paper, we propose 2 approaches for implementing the controlled imputation for binary and ordinal data based respectively on the sequential logistic regression and the multivariate probit model. Efficient Markov chain Monte Carlo algorithms are developed for missing data imputation by using the monotone data augmentation technique for the sequential logistic regression and a parameter-expanded monotone data augmentation scheme for the multivariate probit model. We assess the performance of the proposed procedures by simulation and the analysis of a schizophrenia clinical trial and compare them with the fully conditional specification, last observation carried forward, and baseline observation carried forward imputation methods. Copyright © 2018 John Wiley & Sons, Ltd.
Multivariate decoding of brain images using ordinal regression.
Doyle, O M; Ashburner, J; Zelaya, F O; Williams, S C R; Mehta, M A; Marquand, A F
2013-11-01
Neuroimaging data are increasingly being used to predict potential outcomes or groupings, such as clinical severity, drug dose response, and transitional illness states. In these examples, the variable (target) we want to predict is ordinal in nature. Conventional classification schemes assume that the targets are nominal and hence ignore their ranked nature, whereas parametric and/or non-parametric regression models enforce a metric notion of distance between classes. Here, we propose a novel, alternative multivariate approach that overcomes these limitations - whole brain probabilistic ordinal regression using a Gaussian process framework. We applied this technique to two data sets of pharmacological neuroimaging data from healthy volunteers. The first study was designed to investigate the effect of ketamine on brain activity and its subsequent modulation with two compounds - lamotrigine and risperidone. The second study investigates the effect of scopolamine on cerebral blood flow and its modulation using donepezil. We compared ordinal regression to multi-class classification schemes and metric regression. Considering the modulation of ketamine with lamotrigine, we found that ordinal regression significantly outperformed multi-class classification and metric regression in terms of accuracy and mean absolute error. However, for risperidone ordinal regression significantly outperformed metric regression but performed similarly to multi-class classification both in terms of accuracy and mean absolute error. For the scopolamine data set, ordinal regression was found to outperform both multi-class and metric regression techniques considering the regional cerebral blood flow in the anterior cingulate cortex. Ordinal regression was thus the only method that performed well in all cases. Our results indicate the potential of an ordinal regression approach for neuroimaging data while providing a fully probabilistic framework with elegant approaches for model selection. Copyright © 2013. Published by Elsevier Inc.
Squeezing Interval Change From Ordinal Panel Data: Latent Growth Curves With Ordinal Outcomes
ERIC Educational Resources Information Center
Mehta, Paras D.; Neale, Michael C.; Flay, Brian R.
2004-01-01
A didactic on latent growth curve modeling for ordinal outcomes is presented. The conceptual aspects of modeling growth with ordinal variables and the notion of threshold invariance are illustrated graphically using a hypothetical example. The ordinal growth model is described in terms of 3 nested models: (a) multivariate normality of the…
A mixed-effects regression model for longitudinal multivariate ordinal data.
Liu, Li C; Hedeker, Donald
2006-03-01
A mixed-effects item response theory model that allows for three-level multivariate ordinal outcomes and accommodates multiple random subject effects is proposed for analysis of multivariate ordinal outcomes in longitudinal studies. This model allows for the estimation of different item factor loadings (item discrimination parameters) for the multiple outcomes. The covariates in the model do not have to follow the proportional odds assumption and can be at any level. Assuming either a probit or logistic response function, maximum marginal likelihood estimation is proposed utilizing multidimensional Gauss-Hermite quadrature for integration of the random effects. An iterative Fisher scoring solution, which provides standard errors for all model parameters, is used. An analysis of a longitudinal substance use data set, where four items of substance use behavior (cigarette use, alcohol use, marijuana use, and getting drunk or high) are repeatedly measured over time, is used to illustrate application of the proposed model.
Multivariate geometry as an approach to algal community analysis
Allen, T.F.H.; Skagen, S.
1973-01-01
Multivariate analyses are put in the context of more usual approaches to phycological investigations. The intuitive common-sense involved in methods of ordination, classification and discrimination are emphasised by simple geometric accounts which avoid jargon and matrix algebra. Warnings are given that artifacts result from technique abuses by the naive or over-enthusiastic. An analysis of a simple periphyton data set is presented as an example of the approach. Suggestions are made as to situations in phycological investigations, where the techniques could be appropriate. The discipline is reprimanded for its neglect of the multivariate approach.
Comparing interval estimates for small sample ordinal CFA models
Natesan, Prathiba
2015-01-01
Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading. Therefore, editors and policymakers should continue to emphasize the inclusion of interval estimates in research. PMID:26579002
Comparing interval estimates for small sample ordinal CFA models.
Natesan, Prathiba
2015-01-01
Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading. Therefore, editors and policymakers should continue to emphasize the inclusion of interval estimates in research.
A Composite Likelihood Inference in Latent Variable Models for Ordinal Longitudinal Responses
ERIC Educational Resources Information Center
Vasdekis, Vassilis G. S.; Cagnone, Silvia; Moustaki, Irini
2012-01-01
The paper proposes a composite likelihood estimation approach that uses bivariate instead of multivariate marginal probabilities for ordinal longitudinal responses using a latent variable model. The model considers time-dependent latent variables and item-specific random effects to be accountable for the interdependencies of the multivariate…
McMillen, Robert; Shackelford, Signe
2012-10-01
There is no safe level of exposure to tobacco smoke. More than 60 Mississippi communities have passed smoke-free ordinances in the past six years. Opponents claim that these ordinances harm local businesses. Mississippi law allows municipalities to place a tourism and economic development (TED) tax on local restaurants and hotels/motels. The objective of this study is to examine the impact of these ordinances on TED tax revenues. This study applies a pre/post quasi-experimental design to compare TED tax revenue before and after implementing ordinances. Descriptive analyses indicated that inflation-adjusted tax revenues increased during the 12 months following implementation of smoke-free ordinances while there was no change in aggregated control communities. Multivariate fixed-effects analyses found no statistically significant effect of smoke-free ordinances on hospitality tax revenue. No evidence was found that smoke-free ordinances have an adverse effect on the local hospitality industry.
Applying Multivariate Discrete Distributions to Genetically Informative Count Data.
Kirkpatrick, Robert M; Neale, Michael C
2016-03-01
We present a novel method of conducting biometric analysis of twin data when the phenotypes are integer-valued counts, which often show an L-shaped distribution. Monte Carlo simulation is used to compare five likelihood-based approaches to modeling: our multivariate discrete method, when its distributional assumptions are correct, when they are incorrect, and three other methods in common use. With data simulated from a skewed discrete distribution, recovery of twin correlations and proportions of additive genetic and common environment variance was generally poor for the Normal, Lognormal and Ordinal models, but good for the two discrete models. Sex-separate applications to substance-use data from twins in the Minnesota Twin Family Study showed superior performance of two discrete models. The new methods are implemented using R and OpenMx and are freely available.
Bayesian transformation cure frailty models with multivariate failure time data.
Yin, Guosheng
2008-12-10
We propose a class of transformation cure frailty models to accommodate a survival fraction in multivariate failure time data. Established through a general power transformation, this family of cure frailty models includes the proportional hazards and the proportional odds modeling structures as two special cases. Within the Bayesian paradigm, we obtain the joint posterior distribution and the corresponding full conditional distributions of the model parameters for the implementation of Gibbs sampling. Model selection is based on the conditional predictive ordinate statistic and deviance information criterion. As an illustration, we apply the proposed method to a real data set from dentistry.
Concurrent generation of multivariate mixed data with variables of dissimilar types.
Amatya, Anup; Demirtas, Hakan
2016-01-01
Data sets originating from wide range of research studies are composed of multiple variables that are correlated and of dissimilar types, primarily of count, binary/ordinal and continuous attributes. The present paper builds on the previous works on multivariate data generation and develops a framework for generating multivariate mixed data with a pre-specified correlation matrix. The generated data consist of components that are marginally count, binary, ordinal and continuous, where the count and continuous variables follow the generalized Poisson and normal distributions, respectively. The use of the generalized Poisson distribution provides a flexible mechanism which allows under- and over-dispersed count variables generally encountered in practice. A step-by-step algorithm is provided and its performance is evaluated using simulated and real-data scenarios.
Semiparametric Thurstonian Models for Recurrent Choices: A Bayesian Analysis
ERIC Educational Resources Information Center
Ansari, Asim; Iyengar, Raghuram
2006-01-01
We develop semiparametric Bayesian Thurstonian models for analyzing repeated choice decisions involving multinomial, multivariate binary or multivariate ordinal data. Our modeling framework has multiple components that together yield considerable flexibility in modeling preference utilities, cross-sectional heterogeneity and parameter-driven…
Bayesian Nonparametric Ordination for the Analysis of Microbial Communities.
Ren, Boyu; Bacallado, Sergio; Favaro, Stefano; Holmes, Susan; Trippa, Lorenzo
2017-01-01
Human microbiome studies use sequencing technologies to measure the abundance of bacterial species or Operational Taxonomic Units (OTUs) in samples of biological material. Typically the data are organized in contingency tables with OTU counts across heterogeneous biological samples. In the microbial ecology community, ordination methods are frequently used to investigate latent factors or clusters that capture and describe variations of OTU counts across biological samples. It remains important to evaluate how uncertainty in estimates of each biological sample's microbial distribution propagates to ordination analyses, including visualization of clusters and projections of biological samples on low dimensional spaces. We propose a Bayesian analysis for dependent distributions to endow frequently used ordinations with estimates of uncertainty. A Bayesian nonparametric prior for dependent normalized random measures is constructed, which is marginally equivalent to the normalized generalized Gamma process, a well-known prior for nonparametric analyses. In our prior, the dependence and similarity between microbial distributions is represented by latent factors that concentrate in a low dimensional space. We use a shrinkage prior to tune the dimensionality of the latent factors. The resulting posterior samples of model parameters can be used to evaluate uncertainty in analyses routinely applied in microbiome studies. Specifically, by combining them with multivariate data analysis techniques we can visualize credible regions in ecological ordination plots. The characteristics of the proposed model are illustrated through a simulation study and applications in two microbiome datasets.
Graphical Models for Ordinal Data
Guo, Jian; Levina, Elizaveta; Michailidis, George; Zhu, Ji
2014-01-01
A graphical model for ordinal variables is considered, where it is assumed that the data are generated by discretizing the marginal distributions of a latent multivariate Gaussian distribution. The relationships between these ordinal variables are then described by the underlying Gaussian graphical model and can be inferred by estimating the corresponding concentration matrix. Direct estimation of the model is computationally expensive, but an approximate EM-like algorithm is developed to provide an accurate estimate of the parameters at a fraction of the computational cost. Numerical evidence based on simulation studies shows the strong performance of the algorithm, which is also illustrated on data sets on movie ratings and an educational survey. PMID:26120267
A model for incomplete longitudinal multivariate ordinal data.
Liu, Li C
2008-12-30
In studies where multiple outcome items are repeatedly measured over time, missing data often occur. A longitudinal item response theory model is proposed for analysis of multivariate ordinal outcomes that are repeatedly measured. Under the MAR assumption, this model accommodates missing data at any level (missing item at any time point and/or missing time point). It allows for multiple random subject effects and the estimation of item discrimination parameters for the multiple outcome items. The covariates in the model can be at any level. Assuming either a probit or logistic response function, maximum marginal likelihood estimation is described utilizing multidimensional Gauss-Hermite quadrature for integration of the random effects. An iterative Fisher-scoring solution, which provides standard errors for all model parameters, is used. A data set from a longitudinal prevention study is used to motivate the application of the proposed model. In this study, multiple ordinal items of health behavior are repeatedly measured over time. Because of a planned missing design, subjects answered only two-third of all items at a given point. Copyright 2008 John Wiley & Sons, Ltd.
Saqib, Hafiz Sohaib Ahmed; You, Minsheng
2017-01-01
Conservation biological control emphasizes natural and other non-crop vegetation as a source of natural enemies to focal crops. There is an unmet need for better methods to identify the types of vegetation that are optimal to support specific natural enemies that may colonize the crops. Here we explore the commonality of the spider assemblage—considering abundance and diversity (H)—in brassica crops with that of adjacent non-crop and non-brassica crop vegetation. We employ spatial-based multivariate ordination approaches, hierarchical clustering and spatial eigenvector analysis. The small-scale mixed cropping and high disturbance frequency of southern Chinese vegetation farming offered a setting to test the role of alternate vegetation for spider conservation. Our findings indicate that spider families differ markedly in occurrence with respect to vegetation type. Grassy field margins, non-crop vegetation, taro and sweetpotato harbour spider morphospecies and functional groups that are also present in brassica crops. In contrast, pumpkin and litchi contain spiders not found in brassicas, and so may have little benefit for conservation biological control services for brassicas. Our findings also illustrate the utility of advanced statistical approaches for identifying spatial relationships between natural enemies and the land uses most likely to offer alternative habitats for conservation biological control efforts that generates testable hypotheses for future studies. PMID:29085741
London Measure of Unplanned Pregnancy: guidance for its use as an outcome measure
Hall, Jennifer A; Barrett, Geraldine; Copas, Andrew; Stephenson, Judith
2017-01-01
Background The London Measure of Unplanned Pregnancy (LMUP) is a psychometrically validated measure of the degree of intention of a current or recent pregnancy. The LMUP is increasingly being used worldwide, and can be used to evaluate family planning or preconception care programs. However, beyond recommending the use of the full LMUP scale, there is no published guidance on how to use the LMUP as an outcome measure. Ordinal logistic regression has been recommended informally, but studies published to date have all used binary logistic regression and dichotomized the scale at different cut points. There is thus a need for evidence-based guidance to provide a standardized methodology for multivariate analysis and to enable comparison of results. This paper makes recommendations for the regression method for analysis of the LMUP as an outcome measure. Materials and methods Data collected from 4,244 pregnant women in Malawi were used to compare five regression methods: linear, logistic with two cut points, and ordinal logistic with either the full or grouped LMUP score. The recommendations were then tested on the original UK LMUP data. Results There were small but no important differences in the findings across the regression models. Logistic regression resulted in the largest loss of information, and assumptions were violated for the linear and ordinal logistic regression. Consequently, robust standard errors were used for linear regression and a partial proportional odds ordinal logistic regression model attempted. The latter could only be fitted for grouped LMUP score. Conclusion We recommend the linear regression model with robust standard errors to make full use of the LMUP score when analyzed as an outcome measure. Ordinal logistic regression could be considered, but a partial proportional odds model with grouped LMUP score may be required. Logistic regression is the least-favored option, due to the loss of information. For logistic regression, the cut point for un/planned pregnancy should be between nine and ten. These recommendations will standardize the analysis of LMUP data and enhance comparability of results across studies. PMID:28435343
Gender discrimination may be worse than you think: testing ordinal interactions in power research.
Elias, Steven M; Cropanzano, Russell
2006-04-01
The authors reanalyze the data of a study by S. M. Elias and R. J. Loomis (2004), which aimed to determine how an instructor's gender may influence his or her ability to gain student compliance. S. M. Elias and R. J. Loomis observed few significant gender effects using traditional multivariate analyses of variance. The authors reanalyze this data using the more appropriate statistical techniques for detecting ordinal interactions recommended by M. J. Strube and P. Bobko (1989) and S. M. Elias (2004). An ordinal interaction occurs when 1 cell of a 2 x 2 design is responsible for a significant interaction (e.g., female instructors suffering only when rated by male students). Reanalysis of the data resulted in more robust findings.
Sample size calculations for case-control studies
This R package can be used to calculate the required samples size for unconditional multivariate analyses of unmatched case-control studies. The sample sizes are for a scalar exposure effect, such as binary, ordinal or continuous exposures. The sample sizes can also be computed for scalar interaction effects. The analyses account for the effects of potential confounder variables that are also included in the multivariate logistic model.
Guo, L W; Liu, S Z; Zhang, M; Chen, Q; Zhang, S K; Sun, X B
2017-12-10
Objective: To investigate the effect of fried food intake on the pathogenesis of esophageal cancer and precancerous lesions. Methods: From 2005 to 2013, all the residents aged 40-69 years from 11 counties (cities) where cancer screening of upper gastrointestinal cancer had been conducted in rural areas of Henan province, were recruited as the subjects of study. Information on demography and lifestyle was collected. The residents under study were screened with iodine staining endoscopic examination and biopsy samples were diagnosed pathologically, under standardized criteria. Subjects with high risk were divided into the groups based on their different pathological degrees. Multivariate ordinal logistic regression analysis was used to analyze the relationship between the frequency of fried food intake and esophageal cancer and precancerous lesions. Results: A total number of 8 792 cases with normal esophagus, 3 680 with mild hyperplasia, 972 with moderate hyperplasia, 413 with severe hyperplasia carcinoma in situ, and 336 cases of esophageal cancer were recruited. Results from multivariate logistic regression analysis showed that, when compared with those who did not eat fried food, the intake of fried food (<2 times/week: OR =1.60, 95% CI : 1.40-1.83; ≥2 times/week: OR =2.58, 95% CI : 1.98-3.37) appeared a risk factor for both esophageal cancer or precancerous lesions after adjustment for age, sex, marital status, educational level, body mass index, smoking and alcohol intake. Conclusion: The intake of fried food appeared a risk factor for both esophageal cancer and precancerous lesions.
Gaussian-based routines to impute categorical variables in health surveys.
Yucel, Recai M; He, Yulei; Zaslavsky, Alan M
2011-12-20
The multivariate normal (MVN) distribution is arguably the most popular parametric model used in imputation and is available in most software packages (e.g., SAS PROC MI, R package norm). When it is applied to categorical variables as an approximation, practitioners often either apply simple rounding techniques for ordinal variables or create a distinct 'missing' category and/or disregard the nominal variable from the imputation phase. All of these practices can potentially lead to biased and/or uninterpretable inferences. In this work, we develop a new rounding methodology calibrated to preserve observed distributions to multiply impute missing categorical covariates. The major attractiveness of this method is its flexibility to use any 'working' imputation software, particularly those based on MVN, allowing practitioners to obtain usable imputations with small biases. A simulation study demonstrates the clear advantage of the proposed method in rounding ordinal variables and, in some scenarios, its plausibility in imputing nominal variables. We illustrate our methods on a widely used National Survey of Children with Special Health Care Needs where incomplete values on race posed a valid threat on inferences pertaining to disparities. Copyright © 2011 John Wiley & Sons, Ltd.
Williams, L. Keoki; Buu, Anne
2017-01-01
We propose a multivariate genome-wide association test for mixed continuous, binary, and ordinal phenotypes. A latent response model is used to estimate the correlation between phenotypes with different measurement scales so that the empirical distribution of the Fisher’s combination statistic under the null hypothesis is estimated efficiently. The simulation study shows that our proposed correlation estimation methods have high levels of accuracy. More importantly, our approach conservatively estimates the variance of the test statistic so that the type I error rate is controlled. The simulation also shows that the proposed test maintains the power at the level very close to that of the ideal analysis based on known latent phenotypes while controlling the type I error. In contrast, conventional approaches–dichotomizing all observed phenotypes or treating them as continuous variables–could either reduce the power or employ a linear regression model unfit for the data. Furthermore, the statistical analysis on the database of the Study of Addiction: Genetics and Environment (SAGE) demonstrates that conducting a multivariate test on multiple phenotypes can increase the power of identifying markers that may not be, otherwise, chosen using marginal tests. The proposed method also offers a new approach to analyzing the Fagerström Test for Nicotine Dependence as multivariate phenotypes in genome-wide association studies. PMID:28081206
Generating Multivariate Ordinal Data via Entropy Principles.
Lee, Yen; Kaplan, David
2018-03-01
When conducting robustness research where the focus of attention is on the impact of non-normality, the marginal skewness and kurtosis are often used to set the degree of non-normality. Monte Carlo methods are commonly applied to conduct this type of research by simulating data from distributions with skewness and kurtosis constrained to pre-specified values. Although several procedures have been proposed to simulate data from distributions with these constraints, no corresponding procedures have been applied for discrete distributions. In this paper, we present two procedures based on the principles of maximum entropy and minimum cross-entropy to estimate the multivariate observed ordinal distributions with constraints on skewness and kurtosis. For these procedures, the correlation matrix of the observed variables is not specified but depends on the relationships between the latent response variables. With the estimated distributions, researchers can study robustness not only focusing on the levels of non-normality but also on the variations in the distribution shapes. A simulation study demonstrates that these procedures yield excellent agreement between specified parameters and those of estimated distributions. A robustness study concerning the effect of distribution shape in the context of confirmatory factor analysis shows that shape can affect the robust [Formula: see text] and robust fit indices, especially when the sample size is small, the data are severely non-normal, and the fitted model is complex.
Sampling effort affects multivariate comparisons of stream assemblages
Cao, Y.; Larsen, D.P.; Hughes, R.M.; Angermeier, P.L.; Patton, T.M.
2002-01-01
Multivariate analyses are used widely for determining patterns of assemblage structure, inferring species-environment relationships and assessing human impacts on ecosystems. The estimation of ecological patterns often depends on sampling effort, so the degree to which sampling effort affects the outcome of multivariate analyses is a concern. We examined the effect of sampling effort on site and group separation, which was measured using a mean similarity method. Two similarity measures, the Jaccard Coefficient and Bray-Curtis Index were investigated with 1 benthic macroinvertebrate and 2 fish data sets. Site separation was significantly improved with increased sampling effort because the similarity between replicate samples of a site increased more rapidly than between sites. Similarly, the faster increase in similarity between sites of the same group than between sites of different groups caused clearer separation between groups. The strength of site and group separation completely stabilized only when the mean similarity between replicates reached 1. These results are applicable to commonly used multivariate techniques such as cluster analysis and ordination because these multivariate techniques start with a similarity matrix. Completely stable outcomes of multivariate analyses are not feasible. Instead, we suggest 2 criteria for estimating the stability of multivariate analyses of assemblage data: 1) mean within-site similarity across all sites compared, indicating sample representativeness, and 2) the SD of within-site similarity across sites, measuring sample comparability.
Introduction to uses and interpretation of principal component analyses in forest biology.
J. G. Isebrands; Thomas R. Crow
1975-01-01
The application of principal component analysis for interpretation of multivariate data sets is reviewed with emphasis on (1) reduction of the number of variables, (2) ordination of variables, and (3) applications in conjunction with multiple regression.
Ali, Shehzad; Ronaldson, Sarah
2012-09-01
The predominant method of economic evaluation is cost-utility analysis, which uses cardinal preference elicitation methods, including the standard gamble and time trade-off. However, such approach is not suitable for understanding trade-offs between process attributes, non-health outcomes and health outcomes to evaluate current practices, develop new programmes and predict demand for services and products. Ordinal preference elicitation methods including discrete choice experiments and ranking methods are therefore commonly used in health economics and health service research. Cardinal methods have been criticized on the grounds of cognitive complexity, difficulty of administration, contamination by risk and preference attitudes, and potential violation of underlying assumptions. Ordinal methods have gained popularity because of reduced cognitive burden, lower degree of abstract reasoning, reduced measurement error, ease of administration and ability to use both health and non-health outcomes. The underlying assumptions of ordinal methods may be violated when respondents use cognitive shortcuts, or cannot comprehend the ordinal task or interpret attributes and levels, or use 'irrational' choice behaviour or refuse to trade-off certain attributes. CURRENT USE AND GROWING AREAS: Ordinal methods are commonly used to evaluate preference for attributes of health services, products, practices, interventions, policies and, more recently, to estimate utility weights. AREAS FOR ON-GOING RESEARCH: There is growing research on developing optimal designs, evaluating the rationalization process, using qualitative tools for developing ordinal methods, evaluating consistency with utility theory, appropriate statistical methods for analysis, generalizability of results and comparing ordinal methods against each other and with cardinal measures.
Gentry, Amanda Elswick; Jackson-Cook, Colleen K; Lyon, Debra E; Archer, Kellie J
2015-01-01
The pathological description of the stage of a tumor is an important clinical designation and is considered, like many other forms of biomedical data, an ordinal outcome. Currently, statistical methods for predicting an ordinal outcome using clinical, demographic, and high-dimensional correlated features are lacking. In this paper, we propose a method that fits an ordinal response model to predict an ordinal outcome for high-dimensional covariate spaces. Our method penalizes some covariates (high-throughput genomic features) without penalizing others (such as demographic and/or clinical covariates). We demonstrate the application of our method to predict the stage of breast cancer. In our model, breast cancer subtype is a nonpenalized predictor, and CpG site methylation values from the Illumina Human Methylation 450K assay are penalized predictors. The method has been made available in the ordinalgmifs package in the R programming environment.
Sugihara, Toru; Yasunaga, Hideo; Horiguchi, Hiromasa; Fujimura, Tetsuya; Fushimi, Kiyohide; Yu, Changhong; Kattan, Michael W; Homma, Yukio
2014-12-01
Little is known about the disparity of choices between three urinary diversions after radical cystectomy, focusing on patient and institutional factors. We identified urothelial carcinoma patients who received radical cystectomy with cutaneous ureterostomy, ileal conduit or continent reservoir using the Japanese Diagnosis Procedure Combination database from 2007 to 2012. Data comprised age, sex, comorbidities (converted into the Charlson index), TNM classification (converted into oncological stage), hospitals' academic status, hospital volume, bed volume and geographical region. Multivariate ordinal logistic regression analyses fitted with the proportional odds model were performed to analyze factors affecting urinary diversion choices. For dependent variables, the three diversions were converted into an ordinal variable in order of complexity: cutaneous ureterostomy (reference), ileal conduit and continent reservoir. Geographical variations were also examined by multivariate logistic regression models. A total of 4790 patients (1131 cutaneous ureterostomies [23.6 %], 2970 ileal conduits [62.0 %] and 689 continent reservoirs [14.4 %]) were included. Ordinal logistic regression analyses showed that male sex, lower age, lower Charlson index, early tumor stage, higher hospital volume (≥3.4 cases/year) and larger bed volume (≥450 beds) were significantly associated with the preference of more complex urinary diversion. Significant geographical disparity was also found. Good patient condition and early oncological status, as well as institutional factors, including high hospital volume, large bed volume and specific geographical regions, are independently related to the likelihood of choosing complex diversions. Recognizing this disparity would help reinforce the need for clinical practice uniformity.
ERIC Educational Resources Information Center
Ferrari, Pier Alda; Barbiero, Alessandro
2012-01-01
The increasing use of ordinal variables in different fields has led to the introduction of new statistical methods for their analysis. The performance of these methods needs to be investigated under a number of experimental conditions. Procedures to simulate from ordinal variables are then required. In this article, we deal with simulation from…
ERIC Educational Resources Information Center
Denham, Bryan E.
2009-01-01
Grounded conceptually in social cognitive theory, this research examines how personal, behavioral, and environmental factors are associated with risk perceptions of anabolic-androgenic steroids. Ordinal logistic regression and logit log-linear models applied to data gathered from high-school seniors (N = 2,160) in the 2005 Monitoring the Future…
Wheeler, David C.; Archer, Kellie J.; Burstyn, Igor; Yu, Kai; Stewart, Patricia A.; Colt, Joanne S.; Baris, Dalsu; Karagas, Margaret R.; Schwenn, Molly; Johnson, Alison; Armenti, Karla; Silverman, Debra T.; Friesen, Melissa C.
2015-01-01
Objectives: To evaluate occupational exposures in case–control studies, exposure assessors typically review each job individually to assign exposure estimates. This process lacks transparency and does not provide a mechanism for recreating the decision rules in other studies. In our previous work, nominal (unordered categorical) classification trees (CTs) generally successfully predicted expert-assessed ordinal exposure estimates (i.e. none, low, medium, high) derived from occupational questionnaire responses, but room for improvement remained. Our objective was to determine if using recently developed ordinal CTs would improve the performance of nominal trees in predicting ordinal occupational diesel exhaust exposure estimates in a case–control study. Methods: We used one nominal and four ordinal CT methods to predict expert-assessed probability, intensity, and frequency estimates of occupational diesel exhaust exposure (each categorized as none, low, medium, or high) derived from questionnaire responses for the 14983 jobs in the New England Bladder Cancer Study. To replicate the common use of a single tree, we applied each method to a single sample of 70% of the jobs, using 15% to test and 15% to validate each method. To characterize variability in performance, we conducted a resampling analysis that repeated the sample draws 100 times. We evaluated agreement between the tree predictions and expert estimates using Somers’ d, which measures differences in terms of ordinal association between predicted and observed scores and can be interpreted similarly to a correlation coefficient. Results: From the resampling analysis, compared with the nominal tree, an ordinal CT method that used a quadratic misclassification function and controlled tree size based on total misclassification cost had a slightly better predictive performance that was statistically significant for the frequency metric (Somers’ d: nominal tree = 0.61; ordinal tree = 0.63) and similar performance for the probability (nominal = 0.65; ordinal = 0.66) and intensity (nominal = 0.65; ordinal = 0.65) metrics. The best ordinal CT predicted fewer cases of large disagreement with the expert assessments (i.e. no exposure predicted for a job with high exposure and vice versa) compared with the nominal tree across all of the exposure metrics. For example, the percent of jobs with expert-assigned high intensity of exposure that the model predicted as no exposure was 29% for the nominal tree and 22% for the best ordinal tree. Conclusions: The overall agreements were similar across CT models; however, the use of ordinal models reduced the magnitude of the discrepancy when disagreements occurred. As the best performing model can vary by situation, researchers should consider evaluating multiple CT methods to maximize the predictive performance within their data. PMID:25433003
Confirmatory Factor Analysis of Ordinal Variables with Misspecified Models
ERIC Educational Resources Information Center
Yang-Wallentin, Fan; Joreskog, Karl G.; Luo, Hao
2010-01-01
Ordinal variables are common in many empirical investigations in the social and behavioral sciences. Researchers often apply the maximum likelihood method to fit structural equation models to ordinal data. This assumes that the observed measures have normal distributions, which is not the case when the variables are ordinal. A better approach is…
Correlational Analysis of Ordinal Data: From Pearson's "r" to Bayesian Polychoric Correlation
ERIC Educational Resources Information Center
Choi, Jaehwa; Peters, Michelle; Mueller, Ralph O.
2010-01-01
Correlational analyses are one of the most popular quantitative methods, yet also one of the mostly frequently misused methods in social and behavioral research, especially when analyzing ordinal data from Likert or other rating scales. Although several correlational analysis options have been developed for ordinal data, there seems to be a lack…
Proposed Ordinance for the Regulation of Cable Television. Working Draft.
ERIC Educational Resources Information Center
Chicago City Council, IL.
A model ordinance is proposed for the regulation of cable television in the city of Chicago. It defines the language of the ordinance, sets forth the method of granting franchises, and describes the terms of the franchises. The duties of a commission to regulate cable television are listed and the method of selecting commission members is…
The assignment of scores procedure for ordinal categorical data.
Chen, Han-Ching; Wang, Nae-Sheng
2014-01-01
Ordinal data are the most frequently encountered type of data in the social sciences. Many statistical methods can be used to process such data. One common method is to assign scores to the data, convert them into interval data, and further perform statistical analysis. There are several authors who have recently developed assigning score methods to assign scores to ordered categorical data. This paper proposes an approach that defines an assigning score system for an ordinal categorical variable based on underlying continuous latent distribution with interpretation by using three case study examples. The results show that the proposed score system is well for skewed ordinal categorical data.
ERIC Educational Resources Information Center
Yuan, Kun; McCaffrey, Daniel F.; Savitsky, Terrance D.
2013-01-01
Standardized teaching observation protocols have become increasingly popular in evaluating teaching in recent years. One of such protocols that has gained substantial interest from researchers and practitioners is the Classroom Assessment Scoring System-Secondary (CLASSS). According to the developer, CLASS-S has three domains of teacher-student…
Andrew M. Liebhold; Takehiko Yamanaka; Alain Roques; Sylvie Augustin; Steven L. Chown; Eckehard G. Brockerhoff; Petr Pysek
2016-01-01
Insects are among the world's most ecologically and economically important invasive species. Here we assemble inventories of native and nonnative species from 20 world regions and contrast relative numbers among these species assemblages. Multivariate ordination indicates that the distribution of species among insect orders is completely different between native...
Wilson, Bethany J; Nicholas, Frank W; James, John W; Wade, Claire M; Thomson, Peter C
2013-01-01
Canine hip dysplasia (CHD) is a serious and common musculoskeletal disease of pedigree dogs and therefore represents both an important welfare concern and an imperative breeding priority. The typical heritability estimates for radiographic CHD traits suggest that the accuracy of breeding dog selection could be substantially improved by the use of estimated breeding values (EBVs) in place of selection based on phenotypes of individuals. The British Veterinary Association/Kennel Club scoring method is a complex measure composed of nine bilateral ordinal traits, intended to evaluate both early and late dysplastic changes. However, the ordinal nature of the traits may represent a technical challenge for calculation of EBVs using linear methods. The purpose of the current study was to calculate EBVs of British Veterinary Association/Kennel Club traits in the Australian population of German Shepherd Dogs, using linear (both as individual traits and a summed phenotype), binary and ordinal methods to determine the optimal method for EBV calculation. Ordinal EBVs correlated well with linear EBVs (r = 0.90-0.99) and somewhat well with EBVs for the sum of the individual traits (r = 0.58-0.92). Correlation of ordinal and binary EBVs varied widely (r = 0.24-0.99) depending on the trait and cut-point considered. The ordinal EBVs have increased accuracy (0.48-0.69) of selection compared with accuracies from individual phenotype-based selection (0.40-0.52). Despite the high correlations between linear and ordinal EBVs, the underlying relationship between EBVs calculated by the two methods was not always linear, leading us to suggest that ordinal models should be used wherever possible. As the population of German Shepherd Dogs which was studied was purportedly under selection for the traits studied, we examined the EBVs for evidence of a genetic trend in these traits and found substantial genetic improvement over time. This study suggests the use of ordinal EBVs could increase the rate of genetic improvement in this population.
The effect of ordinances requiring smoke-free restaurants and bars on revenues: a follow-up.
Glantz, S A; Smith, L R
1997-01-01
OBJECTIVES: The purpose of this study was to extend an earlier evaluation of the economic effects of ordinances requiring smoke-free restaurants and bars. METHODS: Sales tax data for 15 cities with smoke-free restaurant ordinances, 5 cities and 2 counties with smoke-free bar ordinances, and matched comparison locations were analyzed by multiple regression, including time and a dummy variable for the ordinance. RESULTS: Ordinances had no significant effect on the fraction of total retail sales that went to eating and drinking places or on the ratio between sales in communities with ordinances and sales in comparison communities. Ordinances requiring smoke-free bars had no significant effect on the fraction of revenues going to eating and drinking places that serve all types of liquor. CONCLUSIONS: Smoke-free ordinances do not adversely affect either restaurant or bar sales. PMID:9357356
2010-01-01
Background Aneurysmal subarachnoid haemorrhage (aSAH) is a devastating event with a frequently disabling outcome. Our aim was to develop a prognostic model to predict an ordinal clinical outcome at two months in patients with aSAH. Methods We studied patients enrolled in the International Subarachnoid Aneurysm Trial (ISAT), a randomized multicentre trial to compare coiling and clipping in aSAH patients. Several models were explored to estimate a patient's outcome according to the modified Rankin Scale (mRS) at two months after aSAH. Our final model was validated internally with bootstrapping techniques. Results The study population comprised of 2,128 patients of whom 159 patients died within 2 months (8%). Multivariable proportional odds analysis identified World Federation of Neurosurgical Societies (WFNS) grade as the most important predictor, followed by age, sex, lumen size of the aneurysm, Fisher grade, vasospasm on angiography, and treatment modality. The model discriminated moderately between those with poor and good mRS scores (c statistic = 0.65), with minor optimism according to bootstrap re-sampling (optimism corrected c statistic = 0.64). Conclusion We presented a calibrated and internally validated ordinal prognostic model to predict two month mRS in aSAH patients who survived the early stage up till a treatment decision. Although generalizability of the model is limited due to the selected population in which it was developed, this model could eventually be used to support clinical decision making after external validation. Trial Registration International Standard Randomised Controlled Trial, Number ISRCTN49866681 PMID:20920243
Mark Borchert; Daniel Norris
1991-01-01
Microhabitat preferences and species-environment patterns were quantified for bryophytes in blue oak woodlands and forests of central coastal California. Presence data for mosses collected from 149 400 m2 plots were analyzed using canonical correspondence analysis (CCA), a multivariate direct gradient analysis technique. Separate ordinations were performed for...
Detecting depth gradients in the mid-Cretaceous Western Interior Seaway
NASA Astrophysics Data System (ADS)
Bryant, R.
2017-12-01
Multivariate data sets can be simplified using techniques like ordination and detrended correspondence analysis to identify important ecological gradients such as water depth, and thus provide insight into the environmental distribution of species (Patzkowsky & Holland, 2012). Here, these methods will be applied to abundance data of foraminiferal assemblages from the Western Interior Seaway through the Cenomanian/Turonian boundary ( 94-93 Ma). Through this interval the seaway experienced rapid and abrupt environmental and oceanographic changes, including the onset of Oceanic Anoxic Event 2 (OAE2) and peak transgression. The intense ocean and biosphere changes are well documented in the WIS, but the effect of OAE2 coupled with rising sea level on foraminiferal communities across the seaway is still poorly understood.
Introducing Students to Plant Geography: Polar Ordination Applied to Hanging Gardens.
ERIC Educational Resources Information Center
Malanson, George P.; And Others
1993-01-01
Reports on a research study in which college students used a statistical ordination method to reveal relationships among plant community structures and physical, disturbance, and spatial variables. Concludes that polar ordination helps students understand the methodology of plant geography and encourages further student research. (CFR)
Clean Indoor Air Ordinance Coverage in the Appalachian Region of the United States
Liber, Alex; Pennell, Michael; Nealy, Darren; Hammer, Jana; Berman, Micah
2010-01-01
Objectives. We sought to quantitatively examine the pattern of, and socioeconomic factors associated with, adoption of clean indoor air ordinances in Appalachia. Methods. We collected and reviewed clean indoor air ordinances in Appalachian communities in 6 states and rated the ordinances for completeness of coverage in workplaces, restaurants, and bars. Additionally, we computed a strength score to measure coverage in 7 locations. We fit mixed-effects models to determine whether the presence of a comprehensive ordinance and the ordinance strength were related to community socioeconomic disadvantage. Results. Of the 332 communities included in the analysis, fewer than 20% had adopted a comprehensive workplace, restaurant, or bar ordinance. Most ordinances were weak, achieving on average only 43% of the total possible points. Communities with a higher unemployment rate were less likely and those with a higher education level were more likely to have a strong ordinance. Conclusions. The majority of residents in these communities are not protected from secondhand smoke. Efforts to pass strong statewide clean indoor air laws should take priority over local initiatives in these states. PMID:20466957
Unified Least Squares Methods for the Evaluation of Diagnostic Tests With the Gold Standard
Tang, Liansheng Larry; Yuan, Ao; Collins, John; Che, Xuan; Chan, Leighton
2017-01-01
The article proposes a unified least squares method to estimate the receiver operating characteristic (ROC) parameters for continuous and ordinal diagnostic tests, such as cancer biomarkers. The method is based on a linear model framework using the empirically estimated sensitivities and specificities as input “data.” It gives consistent estimates for regression and accuracy parameters when the underlying continuous test results are normally distributed after some monotonic transformation. The key difference between the proposed method and the method of Tang and Zhou lies in the response variable. The response variable in the latter is transformed empirical ROC curves at different thresholds. It takes on many values for continuous test results, but few values for ordinal test results. The limited number of values for the response variable makes it impractical for ordinal data. However, the response variable in the proposed method takes on many more distinct values so that the method yields valid estimates for ordinal data. Extensive simulation studies are conducted to investigate and compare the finite sample performance of the proposed method with an existing method, and the method is then used to analyze 2 real cancer diagnostic example as an illustration. PMID:28469385
Ordinal feature selection for iris and palmprint recognition.
Sun, Zhenan; Wang, Libin; Tan, Tieniu
2014-09-01
Ordinal measures have been demonstrated as an effective feature representation model for iris and palmprint recognition. However, ordinal measures are a general concept of image analysis and numerous variants with different parameter settings, such as location, scale, orientation, and so on, can be derived to construct a huge feature space. This paper proposes a novel optimization formulation for ordinal feature selection with successful applications to both iris and palmprint recognition. The objective function of the proposed feature selection method has two parts, i.e., misclassification error of intra and interclass matching samples and weighted sparsity of ordinal feature descriptors. Therefore, the feature selection aims to achieve an accurate and sparse representation of ordinal measures. And, the optimization subjects to a number of linear inequality constraints, which require that all intra and interclass matching pairs are well separated with a large margin. Ordinal feature selection is formulated as a linear programming (LP) problem so that a solution can be efficiently obtained even on a large-scale feature pool and training database. Extensive experimental results demonstrate that the proposed LP formulation is advantageous over existing feature selection methods, such as mRMR, ReliefF, Boosting, and Lasso for biometric recognition, reporting state-of-the-art accuracy on CASIA and PolyU databases.
The effect of ordinances requiring smoke-free restaurants on restaurant sales.
Glantz, S A; Smith, L R
1994-01-01
OBJECTIVES: The effect on restaurant revenues of local ordinances requiring smoke-free restaurants is an important consideration for restauranteurs themselves and the cities that depend on sales tax revenues to provide services. METHODS: Data were obtained from the California State Board of Equalization and Colorado State Department of Revenue on taxable restaurant sales from 1986 (1982 for Aspen) through 1993 for all 15 cities where ordinances were in force, as well as for 15 similar control communities without smoke-free ordinances during this period. These data were analyzed using multiple regression, including time and a dummy variable for whether an ordinance was in force. Total restaurant sales were analyzed as a fraction of total retail sales and restaurant sales in smoke-free cities vs the comparison cities similar in population, median income, and other factors. RESULTS. Ordinances had no significant effect on the fraction of total retail sales that went to restaurants or on the ratio of restaurant sales in communities with ordinances compared with those in the matched control communities. CONCLUSIONS. Smoke-free restaurant ordinances do not adversely affect restaurant sales. PMID:8017529
ERIC Educational Resources Information Center
Linacre, John Michael
Various methods of estimating main effects from ordinal data are presented and contrasted. Problems discussed include: (1) at what level to accumulate ordinal data into linear measures; (2) how to maintain scaling across analyses; and (3) the inevitable confounding of within cell variance with measurement error. An example shows three methods of…
Tencer, John; Carlberg, Kevin; Larsen, Marvin; ...
2017-06-17
Radiation heat transfer is an important phenomenon in many physical systems of practical interest. When participating media is important, the radiative transfer equation (RTE) must be solved for the radiative intensity as a function of location, time, direction, and wavelength. In many heat-transfer applications, a quasi-steady assumption is valid, thereby removing time dependence. The dependence on wavelength is often treated through a weighted sum of gray gases (WSGG) approach. The discrete ordinates method (DOM) is one of the most common methods for approximating the angular (i.e., directional) dependence. The DOM exactly solves for the radiative intensity for a finite numbermore » of discrete ordinate directions and computes approximations to integrals over the angular space using a quadrature rule; the chosen ordinate directions correspond to the nodes of this quadrature rule. This paper applies a projection-based model-reduction approach to make high-order quadrature computationally feasible for the DOM for purely absorbing applications. First, the proposed approach constructs a reduced basis from (high-fidelity) solutions of the radiative intensity computed at a relatively small number of ordinate directions. Then, the method computes inexpensive approximations of the radiative intensity at the (remaining) quadrature points of a high-order quadrature using a reduced-order model constructed from the reduced basis. Finally, this results in a much more accurate solution than might have been achieved using only the ordinate directions used to compute the reduced basis. One- and three-dimensional test problems highlight the efficiency of the proposed method.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tencer, John; Carlberg, Kevin; Larsen, Marvin
Radiation heat transfer is an important phenomenon in many physical systems of practical interest. When participating media is important, the radiative transfer equation (RTE) must be solved for the radiative intensity as a function of location, time, direction, and wavelength. In many heat-transfer applications, a quasi-steady assumption is valid, thereby removing time dependence. The dependence on wavelength is often treated through a weighted sum of gray gases (WSGG) approach. The discrete ordinates method (DOM) is one of the most common methods for approximating the angular (i.e., directional) dependence. The DOM exactly solves for the radiative intensity for a finite numbermore » of discrete ordinate directions and computes approximations to integrals over the angular space using a quadrature rule; the chosen ordinate directions correspond to the nodes of this quadrature rule. This paper applies a projection-based model-reduction approach to make high-order quadrature computationally feasible for the DOM for purely absorbing applications. First, the proposed approach constructs a reduced basis from (high-fidelity) solutions of the radiative intensity computed at a relatively small number of ordinate directions. Then, the method computes inexpensive approximations of the radiative intensity at the (remaining) quadrature points of a high-order quadrature using a reduced-order model constructed from the reduced basis. Finally, this results in a much more accurate solution than might have been achieved using only the ordinate directions used to compute the reduced basis. One- and three-dimensional test problems highlight the efficiency of the proposed method.« less
Rios, Anthony; Kavuluru, Ramakanth
2017-11-01
The CEGS N-GRID 2016 Shared Task in Clinical Natural Language Processing (NLP) provided a set of 1000 neuropsychiatric notes to participants as part of a competition to predict psychiatric symptom severity scores. This paper summarizes our methods, results, and experiences based on our participation in the second track of the shared task. Classical methods of text classification usually fall into one of three problem types: binary, multi-class, and multi-label classification. In this effort, we study ordinal regression problems with text data where misclassifications are penalized differently based on how far apart the ground truth and model predictions are on the ordinal scale. Specifically, we present our entries (methods and results) in the N-GRID shared task in predicting research domain criteria (RDoC) positive valence ordinal symptom severity scores (absent, mild, moderate, and severe) from psychiatric notes. We propose a novel convolutional neural network (CNN) model designed to handle ordinal regression tasks on psychiatric notes. Broadly speaking, our model combines an ordinal loss function, a CNN, and conventional feature engineering (wide features) into a single model which is learned end-to-end. Given interpretability is an important concern with nonlinear models, we apply a recent approach called locally interpretable model-agnostic explanation (LIME) to identify important words that lead to instance specific predictions. Our best model entered into the shared task placed third among 24 teams and scored a macro mean absolute error (MMAE) based normalized score (100·(1-MMAE)) of 83.86. Since the competition, we improved our score (using basic ensembling) to 85.55, comparable with the winning shared task entry. Applying LIME to model predictions, we demonstrate the feasibility of instance specific prediction interpretation by identifying words that led to a particular decision. In this paper, we present a method that successfully uses wide features and an ordinal loss function applied to convolutional neural networks for ordinal text classification specifically in predicting psychiatric symptom severity scores. Our approach leads to excellent performance on the N-GRID shared task and is also amenable to interpretability using existing model-agnostic approaches. Copyright © 2017 Elsevier Inc. All rights reserved.
Quantitative characterisation of audio data by ordinal symbolic dynamics
NASA Astrophysics Data System (ADS)
Aschenbrenner, T.; Monetti, R.; Amigó, J. M.; Bunk, W.
2013-06-01
Ordinal symbolic dynamics has developed into a valuable method to describe complex systems. Recently, using the concept of transcripts, the coupling behaviour of systems was assessed, combining the properties of the symmetric group with information theoretic ideas. In this contribution, methods from the field of ordinal symbolic dynamics are applied to the characterisation of audio data. Coupling complexity between frequency bands of solo violin music, as a fingerprint of the instrument, is used for classification purposes within a support vector machine scheme. Our results suggest that coupling complexity is able to capture essential characteristics, sufficient to distinguish among different violins.
Association of Rhinoplasty With Perceived Attractiveness, Success, and Overall Health.
Nellis, Jason C; Ishii, Masaru; Bater, Kristin L; Papel, Ira D; Kontis, Theda C; Byrne, Patrick J; Boahene, Kofi D O; Ishii, Lisa E
2018-03-01
To date, the impact of rhinoplasty surgery on social perceptions has not been quantified. To measure the association of rhinoplasty with observer-graded perceived attractiveness, success, and overall health. In a web-based survey, blinded casual observers viewed independent images of 13 unique patient faces before or after rhinoplasty. Delphi method was used to select standardized patient images, confirming appropriate patient candidacy and overall surgical effect. Observers rated the attractiveness, perceived success, and perceived overall health for each patient image. Facial perception questions were answered on a visual analog scale from 0 to 100, where higher scores corresponded to more positive responses. A multivariate mixed-effects regression model was used to determine the effect of rhinoplasty while accounting for observer biases. To further characterize the effect of rhinoplasty, estimated ordinal rank change was calculated for each domain. The primary objective was to measure the effect of rhinoplasty on observer-graded perceived attractiveness, success, and overall health. A total of 473 observers (mean age, 29 years [range, 18-73 years]; 305 [70.8%] were female) successfully completed the survey. On multivariate regression, patients after rhinoplasty were rated as significantly more attractive (rhinoplasty effect, 6.26; 95% CI, 5.10-7.41), more successful (rhinoplasty effect, 3.24; 95% CI, 2.32-4.17), and overall healthier (rhinoplasty effect, 3.78; 95% CI, 2.79-4.81). The ordinal rank change for an average individual's perceived attractiveness, success, and overall health was a positive shift of 14, 9, and 10 out of 100 rank positions, respectively. As perceived by casual observers, rhinoplasty surgery was associatedwith perceptions that in patients appeared significantly more attractive, more successful, and healthier. These results suggest patients undergoing rhinoplasty may derive a multifaceted benefit when partaking in social interactions. Furthermore, these results facilitate improved patient discussions aiming to provide more precise surgical expectations with an understanding that these results represent optimal outcomes. NA.
Empirical Histograms in Item Response Theory with Ordinal Data
ERIC Educational Resources Information Center
Woods, Carol M.
2007-01-01
The purpose of this research is to describe, test, and illustrate a new implementation of the empirical histogram (EH) method for ordinal items. The EH method involves the estimation of item response model parameters simultaneously with the approximation of the distribution of the random latent variable (theta) as a histogram. Software for the EH…
Deterministic absorbed dose estimation in computed tomography using a discrete ordinates method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Norris, Edward T.; Liu, Xin, E-mail: xinliu@mst.edu; Hsieh, Jiang
Purpose: Organ dose estimation for a patient undergoing computed tomography (CT) scanning is very important. Although Monte Carlo methods are considered gold-standard in patient dose estimation, the computation time required is formidable for routine clinical calculations. Here, the authors instigate a deterministic method for estimating an absorbed dose more efficiently. Methods: Compared with current Monte Carlo methods, a more efficient approach to estimating the absorbed dose is to solve the linear Boltzmann equation numerically. In this study, an axial CT scan was modeled with a software package, Denovo, which solved the linear Boltzmann equation using the discrete ordinates method. Themore » CT scanning configuration included 16 x-ray source positions, beam collimators, flat filters, and bowtie filters. The phantom was the standard 32 cm CT dose index (CTDI) phantom. Four different Denovo simulations were performed with different simulation parameters, including the number of quadrature sets and the order of Legendre polynomial expansions. A Monte Carlo simulation was also performed for benchmarking the Denovo simulations. A quantitative comparison was made of the simulation results obtained by the Denovo and the Monte Carlo methods. Results: The difference in the simulation results of the discrete ordinates method and those of the Monte Carlo methods was found to be small, with a root-mean-square difference of around 2.4%. It was found that the discrete ordinates method, with a higher order of Legendre polynomial expansions, underestimated the absorbed dose near the center of the phantom (i.e., low dose region). Simulations of the quadrature set 8 and the first order of the Legendre polynomial expansions proved to be the most efficient computation method in the authors’ study. The single-thread computation time of the deterministic simulation of the quadrature set 8 and the first order of the Legendre polynomial expansions was 21 min on a personal computer. Conclusions: The simulation results showed that the deterministic method can be effectively used to estimate the absorbed dose in a CTDI phantom. The accuracy of the discrete ordinates method was close to that of a Monte Carlo simulation, and the primary benefit of the discrete ordinates method lies in its rapid computation speed. It is expected that further optimization of this method in routine clinical CT dose estimation will improve its accuracy and speed.« less
Chen, Ping; Harrington, Peter B
2008-02-01
A new method coupling multivariate self-modeling mixture analysis and pattern recognition has been developed to identify toxic industrial chemicals using fused positive and negative ion mobility spectra (dual scan spectra). A Smiths lightweight chemical detector (LCD), which can measure positive and negative ion mobility spectra simultaneously, was used to acquire the data. Simple-to-use interactive self-modeling mixture analysis (SIMPLISMA) was used to separate the analytical peaks in the ion mobility spectra from the background reactant ion peaks (RIP). The SIMPLSIMA analytical components of the positive and negative ion peaks were combined together in a butterfly representation (i.e., negative spectra are reported with negative drift times and reflected with respect to the ordinate and juxtaposed with the positive ion mobility spectra). Temperature constrained cascade-correlation neural network (TCCCN) models were built to classify the toxic industrial chemicals. Seven common toxic industrial chemicals were used in this project to evaluate the performance of the algorithm. Ten bootstrapped Latin partitions demonstrated that the classification of neural networks using the SIMPLISMA components was statistically better than neural network models trained with fused ion mobility spectra (IMS).
Chen, Jinsong; Zhang, Dake; Choi, Jaehwa
2015-12-01
It is common to encounter latent variables with ordinal data in social or behavioral research. Although a mediated effect of latent variables (latent mediated effect, or LME) with ordinal data may appear to be a straightforward combination of LME with continuous data and latent variables with ordinal data, the methodological challenges to combine the two are not trivial. This research covers model structures as complex as LME and formulates both point and interval estimates of LME for ordinal data using the Bayesian full-information approach. We also combine weighted least squares (WLS) estimation with the bias-corrected bootstrapping (BCB; Efron Journal of the American Statistical Association, 82, 171-185, 1987) method or the traditional delta method as the limited-information approach. We evaluated the viability of these different approaches across various conditions through simulation studies, and provide an empirical example to illustrate the approaches. We found that the Bayesian approach with reasonably informative priors is preferred when both point and interval estimates are of interest and the sample size is 200 or above.
Identification of Users for a Smoking Cessation Mobile App: Quantitative Study
Postel, Marloes G; Pieterse, Marcel E
2018-01-01
Background The number of mobile apps that support smoking cessation is growing, indicating the potential of the mobile phone as a means to support cessation. Knowledge about the potential end users for cessation apps results in suggestions to target potential user groups in a dissemination strategy, leading to a possible increase in the satisfaction and adherence of cessation apps. Objective This study aimed to characterize potential end users for a specific mobile health (mHealth) smoking cessation app. Methods A quantitative study was conducted among 955 Dutch smokers and ex-smokers. The respondents were primarily recruited from addiction care facilities and hospitals through Web-based media via websites and forums. The respondents were surveyed on their demographics, smoking behavior, and personal innovativeness. The intention to use and the attitude toward a cessation app were determined on a 5-point Likert scale. To study the association between the characteristics and intention to use and attitude, univariate and multivariate ordinal logistic regression analyses were performed. Results The multivariate ordinal logistic regression showed that the number of previous quit attempts (odds ratio [OR] 4.1, 95% CI 2.4-7.0, and OR 3.5, 95% CI 2.0-5.9) and the score on the Fagerstrom Test of Nicotine Dependence (OR 0.8, 95% CI 0.8-0.9, and OR 0.8, 95% CI 0.8-0.9) positively correlates with the intention to use a cessation app and the attitude toward cessation apps, respectively. Personal innovativeness also positively correlates with the intention to use (OR 0.3, 95% CI 0.2-0.4) and the attitude towards (OR 0.2, 95% CI 0.1-0.4) a cessation app. No associations between demographics and the intention to use or the attitude toward using a cessation app were observed. Conclusions This study is among the first to show that demographic characteristics such as age and level of education are not associated with the intention to use and the attitude toward using a cessation app when characteristics related specifically to the app, such as nicotine dependency and the number of quit attempts, are present in a multivariate regression model. This study shows that the use of mHealth apps depends on characteristics related to the content of the app rather than general user characteristics. PMID:29631988
Earth's rotation irregularities derived from UTIBLI by method of multi-composing of ordinates
NASA Astrophysics Data System (ADS)
Segan, S.; Damjanov, I.; Surlan, B.
Using the method of multi-composing of ordinates we have identified in Earth's rotation a long-periodic term with a period similar to the relaxation time of Chandler nutation. There was not enough information to assess its origin. We demonstrate that the method can be used even in the case when the data time span is comparable to the period of harmonic component.
Cameron, Isobel M; Scott, Neil W; Adler, Mats; Reid, Ian C
2014-12-01
It is important for clinical practice and research that measurement scales of well-being and quality of life exhibit only minimal differential item functioning (DIF). DIF occurs where different groups of people endorse items in a scale to different extents after being matched by the intended scale attribute. We investigate the equivalence or otherwise of common methods of assessing DIF. Three methods of measuring age- and sex-related DIF (ordinal logistic regression, Rasch analysis and Mantel χ(2) procedure) were applied to Hospital Anxiety Depression Scale (HADS) data pertaining to a sample of 1,068 patients consulting primary care practitioners. Three items were flagged by all three approaches as having either age- or sex-related DIF with a consistent direction of effect; a further three items identified did not meet stricter criteria for important DIF using at least one method. When applying strict criteria for significant DIF, ordinal logistic regression was slightly less sensitive. Ordinal logistic regression, Rasch analysis and contingency table methods yielded consistent results when identifying DIF in the HADS depression and HADS anxiety scales. Regardless of methods applied, investigators should use a combination of statistical significance, magnitude of the DIF effect and investigator judgement when interpreting the results.
Zhang, Xinyan; Li, Bingzong; Han, Huiying; Song, Sha; Xu, Hongxia; Hong, Yating; Yi, Nengjun; Zhuang, Wenzhuo
2018-05-10
Multiple myeloma (MM), like other cancers, is caused by the accumulation of genetic abnormalities. Heterogeneity exists in the patients' response to treatments, for example, bortezomib. This urges efforts to identify biomarkers from numerous molecular features and build predictive models for identifying patients that can benefit from a certain treatment scheme. However, previous studies treated the multi-level ordinal drug response as a binary response where only responsive and non-responsive groups are considered. It is desirable to directly analyze the multi-level drug response, rather than combining the response to two groups. In this study, we present a novel method to identify significantly associated biomarkers and then develop ordinal genomic classifier using the hierarchical ordinal logistic model. The proposed hierarchical ordinal logistic model employs the heavy-tailed Cauchy prior on the coefficients and is fitted by an efficient quasi-Newton algorithm. We apply our hierarchical ordinal regression approach to analyze two publicly available datasets for MM with five-level drug response and numerous gene expression measures. Our results show that our method is able to identify genes associated with the multi-level drug response and to generate powerful predictive models for predicting the multi-level response. The proposed method allows us to jointly fit numerous correlated predictors and thus build efficient models for predicting the multi-level drug response. The predictive model for the multi-level drug response can be more informative than the previous approaches. Thus, the proposed approach provides a powerful tool for predicting multi-level drug response and has important impact on cancer studies.
Semi-supervised learning for ordinal Kernel Discriminant Analysis.
Pérez-Ortiz, M; Gutiérrez, P A; Carbonero-Ruz, M; Hervás-Martínez, C
2016-12-01
Ordinal classification considers those classification problems where the labels of the variable to predict follow a given order. Naturally, labelled data is scarce or difficult to obtain in this type of problems because, in many cases, ordinal labels are given by a user or expert (e.g. in recommendation systems). Firstly, this paper develops a new strategy for ordinal classification where both labelled and unlabelled data are used in the model construction step (a scheme which is referred to as semi-supervised learning). More specifically, the ordinal version of kernel discriminant learning is extended for this setting considering the neighbourhood information of unlabelled data, which is proposed to be computed in the feature space induced by the kernel function. Secondly, a new method for semi-supervised kernel learning is devised in the context of ordinal classification, which is combined with our developed classification strategy to optimise the kernel parameters. The experiments conducted compare 6 different approaches for semi-supervised learning in the context of ordinal classification in a battery of 30 datasets, showing (1) the good synergy of the ordinal version of discriminant analysis and the use of unlabelled data and (2) the advantage of computing distances in the feature space induced by the kernel function. Copyright © 2016 Elsevier Ltd. All rights reserved.
Detection of illegal transfer of videos over the Internet
NASA Astrophysics Data System (ADS)
Chaisorn, Lekha; Sainui, Janya; Manders, Corey
2010-07-01
In this paper, a method for detecting infringements or modifications of a video in real-time is proposed. The method first segments a video stream into shots, after which it extracts some reference frames as keyframes. This process is performed employing a Singular Value Decomposition (SVD) technique developed in this work. Next, for each input video (represented by its keyframes), ordinal-based signature and SIFT (Scale Invariant Feature Transform) descriptors are generated. The ordinal-based method employs a two-level bitmap indexing scheme to construct the index for each video signature. The first level clusters all input keyframes into k clusters while the second level converts the ordinal-based signatures into bitmap vectors. On the other hand, the SIFT-based method directly uses the descriptors as the index. Given a suspect video (being streamed or transferred on the Internet), we generate the signature (ordinal and SIFT descriptors) then we compute similarity between its signature and those signatures in the database based on ordinal signature and SIFT descriptors separately. For similarity measure, besides the Euclidean distance, Boolean operators are also utilized during the matching process. We have tested our system by performing several experiments on 50 videos (each about 1/2 hour in duration) obtained from the TRECVID 2006 data set. For experiments set up, we refer to the conditions provided by TRECVID 2009 on "Content-based copy detection" task. In addition, we also refer to the requirements issued in the call for proposals by MPEG standard on the similar task. Initial result shows that our framework is effective and robust. As compared to our previous work, on top of the achievement we obtained by reducing the storage space and time taken in the ordinal based method, by introducing the SIFT features, we could achieve an overall accuracy in F1 measure of about 96% (improved about 8%).
Overstatement in happiness reporting with ordinal, bounded scale.
Tanaka, Saori C; Yamada, Katsunori; Kitada, Ryo; Tanaka, Satoshi; Sugawara, Sho K; Ohtake, Fumio; Sadato, Norihiro
2016-02-18
There are various methods by which people can express subjective evaluations quantitatively. For example, happiness can be measured on a scale from 1 to 10, and has been suggested as a measure of economic policy. However, there is resistance to these types of measurement from economists, who often regard welfare to be a cardinal, unbounded quantity. It is unclear whether there are differences between subjective evaluation reported on ordinal, bounded scales and on cardinal, unbounded scales. To answer this question, we developed functional magnetic resonance imaging experimental tasks for reporting happiness from monetary gain and the perception of visual stimulus. Subjects tended to report higher values when they used ordinal scales instead of cardinal scales. There were differences in neural activation between ordinal and cardinal reporting scales. The posterior parietal area showed greater activation when subjects used an ordinal scale instead of a cardinal scale. Importantly, the striatum exhibited greater activation when asked to report happiness on an ordinal scale than when asked to report on a cardinal scale. The finding that ordinal (bounded) scales are associated with higher reported happiness and greater activation in the reward system shows that overstatement bias in happiness data must be considered.
NASA Technical Reports Server (NTRS)
Puri, Ishwar K.
2004-01-01
Our goal has been to investigate the influence of both dilution and radiation on the extinction process of nonpremixed flames at low strain rates. Simulations have been performed by using a counterflow code and three radiation models have been included in it, namely, the optically thin, the narrowband, and discrete ordinate models. The counterflow flame code OPPDIFF was modified to account for heat transfer losses by radiation from the hot gases. The discrete ordinate method (DOM) approximation was first suggested by Chandrasekhar for solving problems in interstellar atmospheres. Carlson and Lathrop developed the method for solving multi-dimensional problem in neutron transport. Only recently has the method received attention in the field of heat transfer. Due to the applicability of the discrete ordinate method for thermal radiation problems involving flames, the narrowband code RADCAL was modified to calculate the radiative properties of the gases. A non-premixed counterflow flame was simulated with the discrete ordinate method for radiative emissions. In comparison with two other models, it was found that the heat losses were comparable with the optically thin and simple narrowband model. The optically thin model had the highest heat losses followed by the DOM model and the narrow-band model.
Mapping Quantitative Traits in Unselected Families: Algorithms and Examples
Dupuis, Josée; Shi, Jianxin; Manning, Alisa K.; Benjamin, Emelia J.; Meigs, James B.; Cupples, L. Adrienne; Siegmund, David
2009-01-01
Linkage analysis has been widely used to identify from family data genetic variants influencing quantitative traits. Common approaches have both strengths and limitations. Likelihood ratio tests typically computed in variance component analysis can accommodate large families but are highly sensitive to departure from normality assumptions. Regression-based approaches are more robust but their use has primarily been restricted to nuclear families. In this paper, we develop methods for mapping quantitative traits in moderately large pedigrees. Our methods are based on the score statistic which in contrast to the likelihood ratio statistic, can use nonparametric estimators of variability to achieve robustness of the false positive rate against departures from the hypothesized phenotypic model. Because the score statistic is easier to calculate than the likelihood ratio statistic, our basic mapping methods utilize relatively simple computer code that performs statistical analysis on output from any program that computes estimates of identity-by-descent. This simplicity also permits development and evaluation of methods to deal with multivariate and ordinal phenotypes, and with gene-gene and gene-environment interaction. We demonstrate our methods on simulated data and on fasting insulin, a quantitative trait measured in the Framingham Heart Study. PMID:19278016
Messai, Habib; Farman, Muhammad; Sarraj-Laabidi, Abir; Hammami-Semmar, Asma; Semmar, Nabil
2016-11-17
Olive oils (OOs) show high chemical variability due to several factors of genetic, environmental and anthropic types. Genetic and environmental factors are responsible for natural compositions and polymorphic diversification resulting in different varietal patterns and phenotypes. Anthropic factors, however, are at the origin of different blends' preparation leading to normative, labelled or adulterated commercial products. Control of complex OO samples requires their (i) characterization by specific markers; (ii) authentication by fingerprint patterns; and (iii) monitoring by traceability analysis. These quality control and management aims require the use of several multivariate statistical tools: specificity highlighting requires ordination methods; authentication checking calls for classification and pattern recognition methods; traceability analysis implies the use of network-based approaches able to separate or extract mixed information and memorized signals from complex matrices. This chapter presents a review of different chemometrics methods applied for the control of OO variability from metabolic and physical-chemical measured characteristics. The different chemometrics methods are illustrated by different study cases on monovarietal and blended OO originated from different countries. Chemometrics tools offer multiple ways for quantitative evaluations and qualitative control of complex chemical variability of OO in relation to several intrinsic and extrinsic factors.
NASA Astrophysics Data System (ADS)
Lopes de Oliveira, Paulo Sérgio; Garratt, Richard Charles
1998-11-01
We describe the application of a method for the reconstruction of three-dimensional atomic co-ordinates from a stereo ribbon diagram of a protein when additional information for some of the sidechain positions is available. The method has applications in cases where the 3D co-ordinates have not been made available by any means other than the original publication and are of interest as models for molecular replacement, homology modelling etc. The approach is, on the one hand, more general than other methods which are based on stereo figures which present specific atomic positions, but on the other hand relies on input from a specialist. Its exact implementation will depend on the figure of interest. We have applied the method to the case of the α-d-galactose-binding lectin jacalin with a resultant RMS deviation, compared to the crystal structure, of 1.5 Å for the 133 Cα positions of the α-chain and 2.6 Å for the less regular β-chain. The success of the method depends on the secondary structure of the protein under consideration and the orientation of the stereo diagram itself but can be expected to reproduce the mainchain co-ordinates more accurately than the sidechains. Some ways in which the method may be generalised to other cases are discussed.
Falcaro, Milena; Pickles, Andrew
2007-02-10
We focus on the analysis of multivariate survival times with highly structured interdependency and subject to interval censoring. Such data are common in developmental genetics and genetic epidemiology. We propose a flexible mixed probit model that deals naturally with complex but uninformative censoring. The recorded ages of onset are treated as possibly censored ordinal outcomes with the interval censoring mechanism seen as arising from a coarsened measurement of a continuous variable observed as falling between subject-specific thresholds. This bypasses the requirement for the failure times to be observed as falling into non-overlapping intervals. The assumption of a normal age-of-onset distribution of the standard probit model is relaxed by embedding within it a multivariate Box-Cox transformation whose parameters are jointly estimated with the other parameters of the model. Complex decompositions of the underlying multivariate normal covariance matrix of the transformed ages of onset become possible. The new methodology is here applied to a multivariate study of the ages of first use of tobacco and first consumption of alcohol without parental permission in twins. The proposed model allows estimation of the genetic and environmental effects that are shared by both of these risk behaviours as well as those that are specific. 2006 John Wiley & Sons, Ltd.
Nguyen, Trang Quynh; Webb-Vargas, Yenny; Koning, Ina M; Stuart, Elizabeth A
We investigate a method to estimate the combined effect of multiple continuous/ordinal mediators on a binary outcome: 1) fit a structural equation model with probit link for the outcome and identity/probit link for continuous/ordinal mediators, 2) predict potential outcome probabilities, and 3) compute natural direct and indirect effects. Step 2 involves rescaling the latent continuous variable underlying the outcome to address residual mediator variance/covariance. We evaluate the estimation of risk-difference- and risk-ratio-based effects (RDs, RRs) using the ML, WLSMV and Bayes estimators in Mplus. Across most variations in path-coefficient and mediator-residual-correlation signs and strengths, and confounding situations investigated, the method performs well with all estimators, but favors ML/WLSMV for RDs with continuous mediators, and Bayes for RRs with ordinal mediators. Bayes outperforms WLSMV/ML regardless of mediator type when estimating RRs with small potential outcome probabilities and in two other special cases. An adolescent alcohol prevention study is used for illustration.
Coles, J.F.; Cuffney, T.F.; McMahon, G.; Beaulieu, K.M.
2004-01-01
During August 2000, responses of biological communities (invertebrates, fish, and algae), physical habitat, and water chemistry to urban intensity were compared among 30 streams within 80 miles of Boston, Massachusetts. Sites chosen for sampling represented a gradient of the intensity of urban development (urban intensity) among drainage basins that had minimal natural variability. In this study, spatial differences were used as surrogates for temporal changes to represent the effects of urbanization over time. The degree of urban intensity for each drainage basin was characterized with a standardized urban index (0?100, lowest to highest) derived from land cover, infrastructure, and socioeconomic variables. Multivariate and multimetric analyses were used to compare urban index values with biological, physical, and chemical data to determine how the data indicated responses to urbanization. Multivariate ordinations were derived for the invertebrate-, fish-, and algaecommunity data by use of correspondence analysis, and ordinations were derived for the chemical and physical data by use of principal-component analysis. Site scores from each of the ordinations were plotted in relation to the urban index to test for a response. In all cases, the primary axis scores showed the strongest response to the urban index, indicating that urbanization was a primary factor affecting the data ordination. For the multimetric analyses, each of the biological data sets was used to calculate a series of community metrics. For the sets of chemical and physical data, the individual variables and various combinations of individual variables were used as measured and derived metrics, respectively. Metrics that were generally most responsive to the urban index for each data set included: EPT (Ephemeroptera, Plecoptera, Trichoptera) taxa for invertebrates; cyprinid taxa for fish; diatom taxa for algae; bicarbonate, conductivity, and nitrogen for chemistry; and water depth and temperature for physical habitat. The slopes of the responses generally were higher between the urban index values of 0 to 35, indicating that the greatest change in aquatic health may occur between low and moderate levels of urban intensity. Additionally, many of the responses showed that at urban index values greater than 35, there was a threshold effect where the response variable no longer changed with respect to urban intensity. Recognizing and understanding this type of response is important in management and monitoring programs that rely on decisive interpretations of variable responses. Any biological, physical, or chemical variable that is used to haracterize stream health over a gradient of disturbance would not be a reliable indicator when a level of disturbance is reached where the variable does not respond in a predictable manner.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Larsen, E.W.
A class of Projected Discrete-Ordinates (PDO) methods is described for obtaining iterative solutions of discrete-ordinates problems with convergence rates comparable to those observed using Diffusion Synthetic Acceleration (DSA). The spatially discretized PDO solutions are generally not equal to the DSA solutions, but unlike DSA, which requires great care in the use of spatial discretizations to preserve stability, the PDO solutions remain stable and rapidly convergent with essentially arbitrary spatial discretizations. Numerical results are presented which illustrate the rapid convergence and the accuracy of solutions obtained using PDO methods with commonplace differencing methods.
Measuring information interactions on the ordinal pattern of stock time series
NASA Astrophysics Data System (ADS)
Zhao, Xiaojun; Shang, Pengjian; Wang, Jing
2013-02-01
The interactions among time series as individual components of complex systems can be quantified by measuring to what extent they exchange information among each other. In many applications, one focuses not on the original series but on its ordinal pattern. In such cases, trivial noises appear more likely to be filtered and the abrupt influence of extreme values can be weakened. Cross-sample entropy and inner composition alignment have been introduced as prominent methods to estimate the information interactions of complex systems. In this paper, we modify both methods to detect the interactions among the ordinal pattern of stock return and volatility series, and we try to uncover the information exchanges across sectors in Chinese stock markets.
Co-Ordinating Education during Emergencies and Reconstruction: Challenges and Responsibilities
ERIC Educational Resources Information Center
Sommers, Marc
2004-01-01
While co-ordination is essentially a method of getting institutions to work together, it is clearly not synonymous with togetherness. Undercurrents of suspicion and distrust between individuals and institutional actors can affect important relationships and give rise to enduring misunderstandings and perplexing challenges. Turf battles involving…
Minimization of annotation work: diagnosis of mammographic masses via active learning
NASA Astrophysics Data System (ADS)
Zhao, Yu; Zhang, Jingyang; Xie, Hongzhi; Zhang, Shuyang; Gu, Lixu
2018-06-01
The prerequisite for establishing an effective prediction system for mammographic diagnosis is the annotation of each mammographic image. The manual annotation work is time-consuming and laborious, which becomes a great hindrance for researchers. In this article, we propose a novel active learning algorithm that can adequately address this problem, leading to the minimization of the labeling costs on the premise of guaranteed performance. Our proposed method is different from the existing active learning methods designed for the general problem as it is specifically designed for mammographic images. Through its modified discriminant functions and improved sample query criteria, the proposed method can fully utilize the pairing of mammographic images and select the most valuable images from both the mediolateral and craniocaudal views. Moreover, in order to extend active learning to the ordinal regression problem, which has no precedent in existing studies, but is essential for mammographic diagnosis (mammographic diagnosis is not only a classification task, but also an ordinal regression task for predicting an ordinal variable, viz. the malignancy risk of lesions), multiple sample query criteria need to be taken into consideration simultaneously. We formulate it as a criteria integration problem and further present an algorithm based on self-adaptive weighted rank aggregation to achieve a good solution. The efficacy of the proposed method was demonstrated on thousands of mammographic images from the digital database for screening mammography. The labeling costs of obtaining optimal performance in the classification and ordinal regression task respectively fell to 33.8 and 19.8 percent of their original costs. The proposed method also generated 1228 wins, 369 ties and 47 losses for the classification task, and 1933 wins, 258 ties and 185 losses for the ordinal regression task compared to the other state-of-the-art active learning algorithms. By taking the particularities of mammographic images, the proposed AL method can indeed reduce the manual annotation work to a great extent without sacrificing the performance of the prediction system for mammographic diagnosis.
Minimization of annotation work: diagnosis of mammographic masses via active learning.
Zhao, Yu; Zhang, Jingyang; Xie, Hongzhi; Zhang, Shuyang; Gu, Lixu
2018-05-22
The prerequisite for establishing an effective prediction system for mammographic diagnosis is the annotation of each mammographic image. The manual annotation work is time-consuming and laborious, which becomes a great hindrance for researchers. In this article, we propose a novel active learning algorithm that can adequately address this problem, leading to the minimization of the labeling costs on the premise of guaranteed performance. Our proposed method is different from the existing active learning methods designed for the general problem as it is specifically designed for mammographic images. Through its modified discriminant functions and improved sample query criteria, the proposed method can fully utilize the pairing of mammographic images and select the most valuable images from both the mediolateral and craniocaudal views. Moreover, in order to extend active learning to the ordinal regression problem, which has no precedent in existing studies, but is essential for mammographic diagnosis (mammographic diagnosis is not only a classification task, but also an ordinal regression task for predicting an ordinal variable, viz. the malignancy risk of lesions), multiple sample query criteria need to be taken into consideration simultaneously. We formulate it as a criteria integration problem and further present an algorithm based on self-adaptive weighted rank aggregation to achieve a good solution. The efficacy of the proposed method was demonstrated on thousands of mammographic images from the digital database for screening mammography. The labeling costs of obtaining optimal performance in the classification and ordinal regression task respectively fell to 33.8 and 19.8 percent of their original costs. The proposed method also generated 1228 wins, 369 ties and 47 losses for the classification task, and 1933 wins, 258 ties and 185 losses for the ordinal regression task compared to the other state-of-the-art active learning algorithms. By taking the particularities of mammographic images, the proposed AL method can indeed reduce the manual annotation work to a great extent without sacrificing the performance of the prediction system for mammographic diagnosis.
Impact of San Francisco’s Toy Ordinance on Restaurants and Children’s Food Purchases, 2011–2012
Saelens, Brian E.; Kapphahn, Kristopher I.; Hekler, Eric B.; Buman, Matthew P.; Goldstein, Benjamin A.; Krukowski, Rebecca A.; O’Donohue, Laura S.; Gardner, Christopher D.; King, Abby C.
2014-01-01
Introduction In 2011, San Francisco passed the first citywide ordinance to improve the nutritional standards of children’s meals sold at restaurants by preventing the giving away of free toys or other incentives with meals unless nutritional criteria were met. This study examined the impact of the Healthy Food Incentives Ordinance at ordinance-affected restaurants on restaurant response (eg, toy-distribution practices, change in children’s menus), and the energy and nutrient content of all orders and children’s-meal–only orders purchased for children aged 0 through 12 years. Methods Restaurant responses were examined from January 2010 through March 2012. Parent–caregiver/child dyads (n = 762) who were restaurant customers were surveyed at 2 points before and 1 seasonally matched point after ordinance enactment at Chain A and B restaurants (n = 30) in 2011 and 2012. Results Both restaurant chains responded to the ordinance by selling toys separately from children’s meals, but neither changed their menus to meet ordinance-specified nutrition criteria. Among children for whom children’s meals were purchased, significant decreases in kilocalories, sodium, and fat per order were likely due to changes in children’s side dishes and beverages at Chain A. Conclusion Although the changes at Chain A did not appear to be directly in response to the ordinance, the transition to a more healthful beverage and default side dish was consistent with the intent of the ordinance. Study results underscore the importance of policy wording, support the concept that more healthful defaults may be a powerful approach for improving dietary intake, and suggest that public policies may contribute to positive restaurant changes. PMID:25032837
Messai, Habib; Farman, Muhammad; Sarraj-Laabidi, Abir; Hammami-Semmar, Asma; Semmar, Nabil
2016-01-01
Background. Olive oils (OOs) show high chemical variability due to several factors of genetic, environmental and anthropic types. Genetic and environmental factors are responsible for natural compositions and polymorphic diversification resulting in different varietal patterns and phenotypes. Anthropic factors, however, are at the origin of different blends’ preparation leading to normative, labelled or adulterated commercial products. Control of complex OO samples requires their (i) characterization by specific markers; (ii) authentication by fingerprint patterns; and (iii) monitoring by traceability analysis. Methods. These quality control and management aims require the use of several multivariate statistical tools: specificity highlighting requires ordination methods; authentication checking calls for classification and pattern recognition methods; traceability analysis implies the use of network-based approaches able to separate or extract mixed information and memorized signals from complex matrices. Results. This chapter presents a review of different chemometrics methods applied for the control of OO variability from metabolic and physical-chemical measured characteristics. The different chemometrics methods are illustrated by different study cases on monovarietal and blended OO originated from different countries. Conclusion. Chemometrics tools offer multiple ways for quantitative evaluations and qualitative control of complex chemical variability of OO in relation to several intrinsic and extrinsic factors. PMID:28231172
Bayesian inference for joint modelling of longitudinal continuous, binary and ordinal events.
Li, Qiuju; Pan, Jianxin; Belcher, John
2016-12-01
In medical studies, repeated measurements of continuous, binary and ordinal outcomes are routinely collected from the same patient. Instead of modelling each outcome separately, in this study we propose to jointly model the trivariate longitudinal responses, so as to take account of the inherent association between the different outcomes and thus improve statistical inferences. This work is motivated by a large cohort study in the North West of England, involving trivariate responses from each patient: Body Mass Index, Depression (Yes/No) ascertained with cut-off score not less than 8 at the Hospital Anxiety and Depression Scale, and Pain Interference generated from the Medical Outcomes Study 36-item short-form health survey with values returned on an ordinal scale 1-5. There are some well-established methods for combined continuous and binary, or even continuous and ordinal responses, but little work was done on the joint analysis of continuous, binary and ordinal responses. We propose conditional joint random-effects models, which take into account the inherent association between the continuous, binary and ordinal outcomes. Bayesian analysis methods are used to make statistical inferences. Simulation studies show that, by jointly modelling the trivariate outcomes, standard deviations of the estimates of parameters in the models are smaller and much more stable, leading to more efficient parameter estimates and reliable statistical inferences. In the real data analysis, the proposed joint analysis yields a much smaller deviance information criterion value than the separate analysis, and shows other good statistical properties too. © The Author(s) 2014.
Regenerating time series from ordinal networks.
McCullough, Michael; Sakellariou, Konstantinos; Stemler, Thomas; Small, Michael
2017-03-01
Recently proposed ordinal networks not only afford novel methods of nonlinear time series analysis but also constitute stochastic approximations of the deterministic flow time series from which the network models are constructed. In this paper, we construct ordinal networks from discrete sampled continuous chaotic time series and then regenerate new time series by taking random walks on the ordinal network. We then investigate the extent to which the dynamics of the original time series are encoded in the ordinal networks and retained through the process of regenerating new time series by using several distinct quantitative approaches. First, we use recurrence quantification analysis on traditional recurrence plots and order recurrence plots to compare the temporal structure of the original time series with random walk surrogate time series. Second, we estimate the largest Lyapunov exponent from the original time series and investigate the extent to which this invariant measure can be estimated from the surrogate time series. Finally, estimates of correlation dimension are computed to compare the topological properties of the original and surrogate time series dynamics. Our findings show that ordinal networks constructed from univariate time series data constitute stochastic models which approximate important dynamical properties of the original systems.
Regenerating time series from ordinal networks
NASA Astrophysics Data System (ADS)
McCullough, Michael; Sakellariou, Konstantinos; Stemler, Thomas; Small, Michael
2017-03-01
Recently proposed ordinal networks not only afford novel methods of nonlinear time series analysis but also constitute stochastic approximations of the deterministic flow time series from which the network models are constructed. In this paper, we construct ordinal networks from discrete sampled continuous chaotic time series and then regenerate new time series by taking random walks on the ordinal network. We then investigate the extent to which the dynamics of the original time series are encoded in the ordinal networks and retained through the process of regenerating new time series by using several distinct quantitative approaches. First, we use recurrence quantification analysis on traditional recurrence plots and order recurrence plots to compare the temporal structure of the original time series with random walk surrogate time series. Second, we estimate the largest Lyapunov exponent from the original time series and investigate the extent to which this invariant measure can be estimated from the surrogate time series. Finally, estimates of correlation dimension are computed to compare the topological properties of the original and surrogate time series dynamics. Our findings show that ordinal networks constructed from univariate time series data constitute stochastic models which approximate important dynamical properties of the original systems.
Economic incentives for oak woodland preservation and conservation
Rosi Dagit; Cy Carlberg; Christy Cuba; Thomas Scott
2015-01-01
Numerous ordinances and laws recognize the value of oak trees and woodlands, and dictate serious and expensive consequences for removing or harming them. Unfortunately, the methods used to calculate these values are equally numerous and often inconsistent. More important, these ordinances typically lack economic incentives to avoid impacts to oak woodland values...
Contributions to the Underlying Bivariate Normal Method for Factor Analyzing Ordinal Data
ERIC Educational Resources Information Center
Xi, Nuo; Browne, Michael W.
2014-01-01
A promising "underlying bivariate normal" approach was proposed by Jöreskog and Moustaki for use in the factor analysis of ordinal data. This was a limited information approach that involved the maximization of a composite likelihood function. Its advantage over full-information maximum likelihood was that very much less computation was…
Nguyen, Trang Quynh; Webb-Vargas, Yenny; Koning, Ina M.; Stuart, Elizabeth A.
2016-01-01
We investigate a method to estimate the combined effect of multiple continuous/ordinal mediators on a binary outcome: 1) fit a structural equation model with probit link for the outcome and identity/probit link for continuous/ordinal mediators, 2) predict potential outcome probabilities, and 3) compute natural direct and indirect effects. Step 2 involves rescaling the latent continuous variable underlying the outcome to address residual mediator variance/covariance. We evaluate the estimation of risk-difference- and risk-ratio-based effects (RDs, RRs) using the ML, WLSMV and Bayes estimators in Mplus. Across most variations in path-coefficient and mediator-residual-correlation signs and strengths, and confounding situations investigated, the method performs well with all estimators, but favors ML/WLSMV for RDs with continuous mediators, and Bayes for RRs with ordinal mediators. Bayes outperforms WLSMV/ML regardless of mediator type when estimating RRs with small potential outcome probabilities and in two other special cases. An adolescent alcohol prevention study is used for illustration. PMID:27158217
Marateb, Hamid Reza; Mansourian, Marjan; Adibi, Peyman; Farina, Dario
2014-01-01
Background: selecting the correct statistical test and data mining method depends highly on the measurement scale of data, type of variables, and purpose of the analysis. Different measurement scales are studied in details and statistical comparison, modeling, and data mining methods are studied based upon using several medical examples. We have presented two ordinal–variables clustering examples, as more challenging variable in analysis, using Wisconsin Breast Cancer Data (WBCD). Ordinal-to-Interval scale conversion example: a breast cancer database of nine 10-level ordinal variables for 683 patients was analyzed by two ordinal-scale clustering methods. The performance of the clustering methods was assessed by comparison with the gold standard groups of malignant and benign cases that had been identified by clinical tests. Results: the sensitivity and accuracy of the two clustering methods were 98% and 96%, respectively. Their specificity was comparable. Conclusion: by using appropriate clustering algorithm based on the measurement scale of the variables in the study, high performance is granted. Moreover, descriptive and inferential statistics in addition to modeling approach must be selected based on the scale of the variables. PMID:24672565
Confidence intervals for distinguishing ordinal and disordinal interactions in multiple regression.
Lee, Sunbok; Lei, Man-Kit; Brody, Gene H
2015-06-01
Distinguishing between ordinal and disordinal interaction in multiple regression is useful in testing many interesting theoretical hypotheses. Because the distinction is made based on the location of a crossover point of 2 simple regression lines, confidence intervals of the crossover point can be used to distinguish ordinal and disordinal interactions. This study examined 2 factors that need to be considered in constructing confidence intervals of the crossover point: (a) the assumption about the sampling distribution of the crossover point, and (b) the possibility of abnormally wide confidence intervals for the crossover point. A Monte Carlo simulation study was conducted to compare 6 different methods for constructing confidence intervals of the crossover point in terms of the coverage rate, the proportion of true values that fall to the left or right of the confidence intervals, and the average width of the confidence intervals. The methods include the reparameterization, delta, Fieller, basic bootstrap, percentile bootstrap, and bias-corrected accelerated bootstrap methods. The results of our Monte Carlo simulation study suggest that statistical inference using confidence intervals to distinguish ordinal and disordinal interaction requires sample sizes more than 500 to be able to provide sufficiently narrow confidence intervals to identify the location of the crossover point. (c) 2015 APA, all rights reserved).
Lanting, Rosanne; Nooraee, Nazanin; Werker, Paul M N; van den Heuvel, Edwin R
2014-09-01
Dupuytren disease affects fingers in a variable fashion. Knowledge about specific disease patterns (phenotype) based on location and severity of the disease is lacking. In this cross-sectional study, 344 primary affected hands with Dupuytren disease were physically examined. The Pearson correlation coefficient between the coexistence of Dupuytren disease in pairs of fingers was calculated, and agglomerative hierarchical clustering was applied to identify possible clusters of affected fingers. With a multivariate ordinal logit model, the authors studied the correlation on severity, taking into account age and sex, and tested hypotheses on independence between groups of fingers. The ring finger was most frequently affected by Dupuytren disease, and contractures were seen in 15.1 percent of affected rays. The severity of thumb and index finger, middle and ring fingers, and middle and little fingers was significantly correlated. Occurrences in pairs of fingers were highest in the middle and ring fingers and lowest in the thumb and index finger. Correlation between the ring and little fingers and a correlation between fingers from the ulnar and radial sides could not be demonstrated. Rays on the ulnar side of the hand are predominantly affected. The middle finger is substantially correlated with other fingers on the ulnar side, and the thumb and index finger are correlated; however, there was no evidence that the ulnar side and the radial side were correlated in any way, which suggests that occurrence on one side of the hand does not predict Dupuytren disease on the other side of the hand. Risk, III.
Kim, O; Kim, M S; Kim, J; Lee, J E; Jung, H
2018-01-17
Most studies regarding the relationship between binge eating disorder (BED) and depression have targeted obese populations. However, nurses, particularly female nurses, are one of the vocations that face these issues due to various reasons including high stress and shift work. This study investigated the prevalence of BED and the correlation between BED and severity of self-reported depressive symptoms among female nurses in South Korea. Participants were 7,267 female nurses, of which 502 had symptoms of BED. Using the propensity score matching (PSM) technique, 502 nurses with BED and 502 without BED were included in the analyses. Data were analyzed using descriptive statistics, Spearman's correlation, and multivariable ordinal logistic regression analysis. The proportion of binge eating disorder was 6.90% among the nurses, and 81.3% of nurses displayed some levels of depressive symptoms. Multivariable ordinal logistic regression analysis revealed that age (40 years old and older), alcohol consumption (frequent drinkers), self-rated health, sleep problems, and stress were associated with self-reported depression symptoms. Overall, after adjusting for confounders, nurses with BED had 1.80 times the risk (95% CI = [1.41-2.30]; p-value < 0.001) of experiencing a greater severity of self-reported depression symptoms. Korean female nurse showed a higher prevalence of both binge eating disorder and depressive symptoms, and the association between the two factors was proven in the study. Therefore, hospital management and health policy makers should be alarmed and agreed on both examining nurses on such problems and providing organized and systematic assistance.
NASA Technical Reports Server (NTRS)
Korkin, Sergey V.; Lyapustin, Alexei I.; Rozanov, Vladimir V.
2012-01-01
A numerical accuracy analysis of the radiative transfer equation (RTE) solution based on separation of the diffuse light field into anisotropic and smooth parts is presented. The analysis uses three different algorithms based on the discrete ordinate method (DOM). Two methods, DOMAS and DOM2+, that do not use the truncation of the phase function, are compared against the TMS-method. DOMAS and DOM2+ use the Small-Angle Modification of RTE and the single scattering term, respectively, as an anisotropic part. The TMS method uses Delta-M method for truncation of the phase function along with the single scattering correction. For reference, a standard discrete ordinate method, DOM, is also included in analysis. The obtained results for cases with high scattering anisotropy show that at low number of streams (16, 32) only DOMAS provides an accurate solution in the aureole area. Outside of the aureole, the convergence and accuracy of DOMAS, and TMS is found to be approximately similar: DOMAS was found more accurate in cases with coarse aerosol and liquid water cloud models, except low optical depth, while the TMS showed better results in case of ice cloud.
Smith, Tyler C; Smith, Besa; Corbeil, Thomas E; Riddle, James R; Ryan, Margaret A K
2004-08-01
There is much concern over the potential for short- and long-term adverse mental health effects caused by the terrorist attacks on September 11, 2001. This analysis used data from the Millennium Cohort Study to identify subgroups of US military members who enrolled in the cohort and reported their mental health status before the traumatic events of September 11 and soon after September 11. While adjusting for confounding, multivariable logistic regression, analysis of variance, and multivariate ordinal, or polychotomous logistic regression were used to compare 18 self-reported mental health measures in US military members who enrolled in the cohort before September 11, 2001 with those military personnel who enrolled after September 11, 2001. In contrast to studies of other populations, military respondents reported fewer mental health problems in the months immediately after September 11, 2001.
ERIC Educational Resources Information Center
Dallat, Clare
2009-01-01
This paper examines the risk communication strategies currently being employed by seven outdoor education co-ordinators in Government schools in Victoria, Australia. Of particular interest are the beliefs and assumptions held by these co-ordinators in relation to communicating risk with parents. Current policy stipulates that parents must be…
Rate My Stake: Interpretation of Ordinal Stake Ratings
Patricia Lebow; Grant Kirker
2014-01-01
Ordinal rating systems are commonly employed to evaluate biodeterioration of wood exposed outdoors over long periods of time. The purpose of these ratings is to compare the durability of test systems to nondurable wood products or known durable wood products. There are many reasons why these systems have evolved as the chosen method of evaluation, including having an...
Association Between Inpatient Sleep Loss and Hyperglycemia of Hospitalization
DePietro, Regina H.; Knutson, Kristen L.; Spampinato, Lisa; Anderson, Samantha L.; Meltzer, David O.; Van Cauter, Eve
2017-01-01
OBJECTIVE To determine whether inpatient sleep duration and efficiency are associated with a greater risk of hyperglycemia in hospitalized patients with and without diabetes. RESEARCH DESIGN AND METHODS In this retrospective analysis of a prospective cohort study, medical inpatients ≥50 years of age were interviewed, and their charts were reviewed to obtain demographic data and diagnosis. Using World Health Organization criteria, patients were categorized as having normal blood glucose, impaired fasting blood glucose, or hyperglycemia based on morning glucose from the electronic health record. Wrist actigraphy measured sleep. Multivariable ordinal logistic regression models, controlling for subject random effects, tested the association between inpatient sleep duration and proportional odds of hyperglycemia versus impaired fasting blood glucose or impaired fasting blood glucose versus normal blood glucose in hospitalized adults. RESULTS A total of 212 patients (60% female and 74% African American) were enrolled. Roughly one-third (73, 34%) had diabetes. Objective inpatient sleep measures did not differ between patients with or without diabetes. In ordinal logistic regression models, each additional hour of in-hospital sleep was associated with an 11% (odds ratio 0.89 [95% CI 0.80, 0.99]; P = 0.043) lower proportional odds of a higher glucose category the next morning (hyperglycemia vs. elevated and elevated vs. normal). Every 10% increase in sleep efficiency was associated with an 18% lower proportional odds of a higher glucose category (odds ratio 0.82 [95% CI 0.74, 0.89]; P < 0.001). CONCLUSIONS Among medical inpatients, both shorter sleep duration and worse sleep efficiency were independently associated with greater proportional odds of hyperglycemia and impaired fasting glucose. PMID:27903614
Zarb, Francis; McEntee, Mark F; Rainford, Louise
2015-06-01
To evaluate visual grading characteristics (VGC) and ordinal regression analysis during head CT optimisation as a potential alternative to visual grading assessment (VGA), traditionally employed to score anatomical visualisation. Patient images (n = 66) were obtained using current and optimised imaging protocols from two CT suites: a 16-slice scanner at the national Maltese centre for trauma and a 64-slice scanner in a private centre. Local resident radiologists (n = 6) performed VGA followed by VGC and ordinal regression analysis. VGC alone indicated that optimised protocols had similar image quality as current protocols. Ordinal logistic regression analysis provided an in-depth evaluation, criterion by criterion allowing the selective implementation of the protocols. The local radiology review panel supported the implementation of optimised protocols for brain CT examinations (including trauma) in one centre, achieving radiation dose reductions ranging from 24 % to 36 %. In the second centre a 29 % reduction in radiation dose was achieved for follow-up cases. The combined use of VGC and ordinal logistic regression analysis led to clinical decisions being taken on the implementation of the optimised protocols. This improved method of image quality analysis provided the evidence to support imaging protocol optimisation, resulting in significant radiation dose savings. • There is need for scientifically based image quality evaluation during CT optimisation. • VGC and ordinal regression analysis in combination led to better informed clinical decisions. • VGC and ordinal regression analysis led to dose reductions without compromising diagnostic efficacy.
Application of the first collision source method to CSNS target station shielding calculation
NASA Astrophysics Data System (ADS)
Zheng, Ying; Zhang, Bin; Chen, Meng-Teng; Zhang, Liang; Cao, Bo; Chen, Yi-Xue; Yin, Wen; Liang, Tian-Jiao
2016-04-01
Ray effects are an inherent problem of the discrete ordinates method. RAY3D, a functional module of ARES, which is a discrete ordinates code system, employs a semi-analytic first collision source method to mitigate ray effects. This method decomposes the flux into uncollided and collided components, and then calculates them with an analytical method and discrete ordinates method respectively. In this article, RAY3D is validated by the Kobayashi benchmarks and applied to the neutron beamline shielding problem of China Spallation Neutron Source (CSNS) target station. The numerical results of the Kobayashi benchmarks indicate that the solutions of DONTRAN3D with RAY3D agree well with the Monte Carlo solutions. The dose rate at the end of the neutron beamline is less than 10.83 μSv/h in the CSNS target station neutron beamline shutter model. RAY3D can effectively mitigate the ray effects and obtain relatively reasonable results. Supported by Major National S&T Specific Program of Large Advanced Pressurized Water Reactor Nuclear Power Plant (2011ZX06004-007), National Natural Science Foundation of China (11505059, 11575061), and the Fundamental Research Funds for the Central Universities (13QN34).
Chakraborty, Arindom
2016-12-01
A common objective in longitudinal studies is to characterize the relationship between a longitudinal response process and a time-to-event data. Ordinal nature of the response and possible missing information on covariates add complications to the joint model. In such circumstances, some influential observations often present in the data may upset the analysis. In this paper, a joint model based on ordinal partial mixed model and an accelerated failure time model is used, to account for the repeated ordered response and time-to-event data, respectively. Here, we propose an influence function-based robust estimation method. Monte Carlo expectation maximization method-based algorithm is used for parameter estimation. A detailed simulation study has been done to evaluate the performance of the proposed method. As an application, a data on muscular dystrophy among children is used. Robust estimates are then compared with classical maximum likelihood estimates. © The Author(s) 2014.
Coles, James F.; Cuffney, Thomas F.; McMahon, Gerard; Beaulieu, Karen M.
2004-01-01
During August 2000, responses of biological communities (invertebrates, fish, and algae), physical habitat, and water chemistry to urban intensity were compared among 30 streams within 80 miles of Boston, Massachusetts. Sites chosen for sampling represented a gradient of the intensity of urban development (urban intensity) among drainage basins that had minimal natural variability. In this study, spatial differences were used as surrogates for temporal changes to represent the effects of urbanization over time. The degree of urban intensity for each drainage basin was characterized with a standardized urban index (0-100, lowest to highest) derived from land cover, infrastructure, and socioeconomic variables. Multivariate and multimetric analyses were used to compare urban index values with biological, physical, and chemical data to determine how the data indicated responses to urbanization. Multivariate ordinations were derived for the invertebrate-, fish-, and algae-community data by use of correspondence analysis, and ordinations were derived for the chemical and physical data by use of principal-component analysis. Site scores from each of the ordinations were plotted in relation to the urban index to test for a response. In all cases, the primary axis scores showed the strongest response to the urban index, indicating that urbanization was a primary factor affecting the data ordination. For the multimetric analyses, each of the biological data sets was used to calculate a series of community metrics. For the sets of chemical and physical data, the individual variables and various combinations of individual variables were used as measured and derived metrics, respectively. Metrics that were generally most responsive to the urban index for each data set included: EPT (Ephemeroptera, Plecoptera, Trichoptera) taxa for invertebrates; cyprinid taxa for fish; diatom taxa for algae; bicarbonate, conductivity, and nitrogen for chemistry; and water depth and temperature for physical habitat. The slopes of the responses generally were higher between the urban index values of 0 to 35, indicating that the greatest change in aquatic health may occur between low and moderate levels of urban intensity. Additionally, many of the responses showed that at urban index values greater than 35, there was a threshold effect where the response variable no longer changed with respect to urban intensity. Recognizing and understanding this type of response is important in management and monitoring programs that rely on decisive interpretations of variable responses. Any biological, physical, or chemical variable that is used to characterize stream health over a gradient of disturbance would not be a reliable indicator when a level of disturbance is reached where the variable does not respond in a predictable manner.
PRIM versus CART in subgroup discovery: when patience is harmful.
Abu-Hanna, Ameen; Nannings, Barry; Dongelmans, Dave; Hasman, Arie
2010-10-01
We systematically compare the established algorithms CART (Classification and Regression Trees) and PRIM (Patient Rule Induction Method) in a subgroup discovery task on a large real-world high-dimensional clinical database. Contrary to current conjectures, PRIM's performance was generally inferior to CART's. PRIM often considered "peeling of" a large chunk of data at a value of a relevant discrete ordinal variable unattractive, ultimately missing an important subgroup. This finding has considerable significance in clinical medicine where ordinal scores are ubiquitous. PRIM's utility in clinical databases would increase when global information about (ordinal) variables is better put to use and when the search algorithm keeps track of alternative solutions.
Discrete ordinates-Monte Carlo coupling: A comparison of techniques in NERVA radiation analysis
NASA Technical Reports Server (NTRS)
Lindstrom, D. G.; Normand, E.; Wilcox, A. D.
1972-01-01
In the radiation analysis of the NERVA nuclear rocket system, two-dimensional discrete ordinates calculations are sufficient to provide detail in the pressure vessel and reactor assembly. Other parts of the system, however, require three-dimensional Monte Carlo analyses. To use these two methods in a single analysis, a means of coupling was developed whereby the results of a discrete ordinates calculation can be used to produce source data for a Monte Carlo calculation. Several techniques for producing source detail were investigated. Results of calculations on the NERVA system are compared and limitations and advantages of the coupling techniques discussed.
Ordinal pattern statistics for the assessment of heart rate variability
NASA Astrophysics Data System (ADS)
Graff, G.; Graff, B.; Kaczkowska, A.; Makowiec, D.; Amigó, J. M.; Piskorski, J.; Narkiewicz, K.; Guzik, P.
2013-06-01
The recognition of all main features of a healthy heart rhythm (the so-called sinus rhythm) is still one of the biggest challenges in contemporary cardiology. Recently the interesting physiological phenomenon of heart rate asymmetry has been observed. This phenomenon is related to unbalanced contributions of heart rate decelerations and accelerations to heart rate variability. In this paper we apply methods based on the concept of ordinal pattern to the analysis of electrocardiograms (inter-peak intervals) of healthy subjects in the supine position. This way we observe new regularities of the heart rhythm related to the distribution of ordinal patterns of lengths 3 and 4.
NASA Astrophysics Data System (ADS)
Christenson, J. G.; Austin, R. A.; Phillips, R. J.
2018-05-01
The phonon Boltzmann transport equation is used to analyze model problems in one and two spatial dimensions, under transient and steady-state conditions. New, explicit solutions are obtained by using the P1 and P3 approximations, based on expansions in spherical harmonics, and are compared with solutions from the discrete ordinates method. For steady-state energy transfer, it is shown that analytic expressions derived using the P1 and P3 approximations agree quantitatively with the discrete ordinates method, in some cases for large Knudsen numbers, and always for Knudsen numbers less than unity. However, for time-dependent energy transfer, the PN solutions differ qualitatively from converged solutions obtained by the discrete ordinates method. Although they correctly capture the wave-like behavior of energy transfer at short times, the P1 and P3 approximations rely on one or two wave velocities, respectively, yielding abrupt, step-changes in temperature profiles that are absent when the angular dependence of the phonon velocities is captured more completely. It is shown that, with the gray approximation, the P1 approximation is formally equivalent to the so-called "hyperbolic heat equation." Overall, these results support the use of the PN approximation to find solutions to the phonon Boltzmann transport equation for steady-state conditions. Such solutions can be useful in the design and analysis of devices that involve heat transfer at nanometer length scales, where continuum-scale approaches become inaccurate.
Dissimilarity measure based on ordinal pattern for physiological signals
NASA Astrophysics Data System (ADS)
Wang, Jing; Shang, Pengjian; Shi, Wenbin; Cui, Xingran
2016-08-01
Complex physiologic signals may carry information of their underlying mechanisms. In this paper, we introduce a dissimilarity measure to capture the features of underlying dynamics from various types of physiologic signals based on rank order statistics of ordinal patterns. Simulated 1/f noise and white noise are used to evaluate the effect of data length, embedding dimension and time delay on this measure. We then apply this measure to different physiologic signals. The method can successfully characterize the unique underlying patterns of subjects at similar physiologic states. It can also serve as a good discriminative tool for the healthy young, healthy elderly, congestive heart failure, atrial fibrilation and white noise groups. Furthermore, when investigated into the details of underlying ordinal patterns for each group, it is found that the distributions of ordinal patterns varies significantly for healthy and pathologic states, as well as aging.
Shielding analyses: the rabbit vs the turtle?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broadhead, B.L.
1996-12-31
This paper compares solutions using Monte Carlo and discrete- ordinates methods applied to two actual shielding situations in order to make some general observations concerning the efficiency and advantages/disadvantages of the two approaches. The discrete- ordinates solutions are performed using two-dimensional geometries, while the Monte Carlo approaches utilize three-dimensional geometries with both multigroup and point cross-section data.
Gender differences in health-related quality of life of adolescents with cystic fibrosis
Arrington-Sanders, Renata; Yi, Michael S; Tsevat, Joel; Wilmott, Robert W; Mrus, Joseph M; Britto, Maria T
2006-01-01
Background Female patients with cystic fibrosis (CF) have consistently poorer survival rates than males across all ages. To determine if gender differences exist in health-related quality of life (HRQOL) of adolescent patients with CF, we performed a cross-section analysis of CF patients recruited from 2 medical centers in 2 cities during 1997–2001. Methods We used the 87-item child self-report form of the Child Health Questionnaire to measure 12 health domains. Data was also collected on age and forced expiratory volume in 1 second (FEV1). We analyzed data from 98 subjects and performed univariate analyses and linear regression or ordinal logistic regression for multivariable analyses. Results The mean (SD) age was 14.6 (2.5) years; 50 (51.0%) were female; and mean FEV1 was 71.6% (25.6%) of predicted. There were no statistically significant gender differences in age or FEV1. In univariate analyses, females reported significantly poorer HRQOL in 5 of the 12 domains. In multivariable analyses controlling for FEV1 and age, we found that female gender was associated with significantly lower global health (p < 0.05), mental health (p < 0.01), and general health perceptions (p < 0.05) scores. Conclusion Further research will need to focus on the causes of these differences in HRQOL and on potential interventions to improve HRQOL of adolescent patients with CF. PMID:16433917
Krause, Kathleen H.
2015-01-01
Objective To provide the first study in Vietnam of how gendered social learning about violence and exposure to non-family institutions influence women’s attitudes about a wife’s recourse after physical IPV. Method A probability sample of 532 married women, ages 18–50 years, was surveyed in July–August, 2012 in Mỹ Hào district. We fit a multivariate linear regression model to estimate correlates of favoring recourse in six situations using a validated attitudinal scale. We split attitudes towards recourse into three subscales (disfavor silence, favor informal recourse, favor formal recourse) and fit one multivariate ordinal logistic regression model for each behavior to estimate correlates of favoring recourse. Results On average, women favored recourse in 2.8 situations. Women who were older and had witnessed physical IPV in childhood had less favorable attitudes about recourse. Women who were hit as children, had completed more schooling, worked outside agriculture, and had sought recourse after IPV had more favorable attitudes about recourse. Conclusions Normative change among women may require efforts to curb family violence, counsel those exposed to violence in childhood, and enhance women’s opportunities for higher schooling and non-agricultural wage work. The state and organizations working on IPV might overcome pockets of unfavorable public opinion by enforcing accountability for IPV rather than seeking to alter ideas about recourse among women. PMID:28392967
Guo, L W; Liu, S Z; Zhang, M; Chen, Q; Zhang, S K; Sun, X B
2018-02-06
Objective: To investigate the effect of fried food intake on the pathogenesis of gastric cancer and precancerous lesions. Methods: From 2005 to 2013, the residents aged 40-69 years from 11 counties/cities where cancer screening of upper gastrointestinal cancer were conducted in rural areas of Henan province as the subjects (82 367 cases). The information such as demography and lifestyle was collected. The residents were screened with endoscopic examination. The biopsy sampleswere diagnosed pathologically, according to pathological diagnosis criteria, the subjects with high risk were divided into the groups with different pathological degrees. The multivariate ordinal logistic regression analysis was used to analyze the relationship between the frequency of fried food intake and gastric cancer and precancerous lesions. Results: The study coverd 46 425 males and 35 942 females, with a age of (53.46±8.07)years. The study collected 6 707 cases of normal stomach, 2 325 cases of low grade intraepithelial neoplasia, 226 cases of high grade intraepithelial neoplasia and 331 cases of gastric cancer. Multivariate logistic regression analysis showed that, compared with those whoeat fried food less than one time per week, fried foods intake (<2 times/week: OR= 1.89, 95 %CI: 1.57-2.28; ≥ 2 times/week: OR= 1.91, 95 %CI: 1.66-2.20) were a risk factor for gastric cancer and precancerous lesions after adjustment for age, sex, marital status, educational level, body mass index (BMI), smoking and drinking status. Conclusion: The intake of fried food is a risk factor for gastric cancer and precancerous lesions. Therefore, reducing the intake of fried food can prevent the occurrence of gastric carcinoma and precancerous lesions.
Preventing homicide: an evaluation of the efficacy of a Detroit gun ordinance.
O'Carroll, P W; Loftin, C; Waller, J B; McDowall, D; Bukoff, A; Scott, R O; Mercy, J A; Wiersema, B
1991-01-01
BACKGROUND: In November 1986, a Detroit, Michigan city ordinance requiring mandatory jail sentences for illegally carrying a firearm in public was passed to preserve "the public peace, health, safety, and welfare of the people." METHODS: We conducted a set of interrupted time-series analyses to evaluate the impact of the law on the incidence of homicides, hypothesizing that the ordinance, by its nature, would affect only firearm homicides and homicides committed outside (e.g., on the street). RESULTS: The incidence of homicide in general increased after the law was passed, but the increases in non-firearm homicides and homicides committed inside (e.g., in a home) were either statistically significant or approached statistical significance (p = .006 and p = .070, respectively), whereas changes in the incidence of firearm homicides and homicides committed outside were not statistically significant (p = .238 and p = .418, respectively). We also determined that the ordinance was essentially unenforced, apparently because of a critical shortage of jail space. CONCLUSIONS: Our findings are consistent with a model in which the ordinance had a dampening effect on firearm homicides occurring in public in Detroit. The apparent preventive effect evident in the time series analyses may have been due to publicity about the ordinance, whereas the small nature of the effect may have been due to the lack of enforcement. PMID:2014857
The impact of ordinate scaling on the visual analysis of single-case data.
Dart, Evan H; Radley, Keith C
2017-08-01
Visual analysis is the primary method for detecting the presence of treatment effects in graphically displayed single-case data and it is often referred to as the "gold standard." Although researchers have developed standards for the application of visual analysis (e.g., Horner et al., 2005), over- and underestimation of effect size magnitude is not uncommon among analysts. Several characteristics have been identified as potential contributors to these errors; however, researchers have largely focused on characteristics of the data itself (e.g., autocorrelation), paying less attention to characteristics of the graphic display which are largely in control of the analyst (e.g., ordinate scaling). The current study investigated the impact that differences in ordinate scaling, a graphic display characteristic, had on experts' accuracy in judgments regarding the magnitude of effect present in single-case percentage data. 32 participants were asked to evaluate eight ABAB data sets (2 each presenting null, small, moderate, and large effects) along with three iterations of each (32 graphs in total) in which only the ordinate scale was manipulated. Results suggest that raters are less accurate in their detection of treatment effects as the ordinate scale is constricted. Additionally, raters were more likely to overestimate the size of a treatment effect when the ordinate scale was constricted. Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Borst, Jordi; Berkhemer, Olvert A; Roos, Yvo B W E M; van Bavel, Ed; van Zwam, Wim H; van Oostenbrugge, Robert J; van Walderveen, Marianne A A; Lingsma, Hester F; van der Lugt, Aad; Dippel, Diederik W J; Yoo, Albert J; Marquering, Henk A; Majoie, Charles B L M
2015-12-01
The utility of computed tomographic perfusion (CTP)-based patient selection for intra-arterial treatment of acute ischemic stroke has not been proven in randomized trials and requires further study in a cohort that was not selected based on CTP. Our objective was to study the relationship between CTP-derived parameters and outcome and treatment effect in patients with acute ischemic stroke because of a proximal intracranial arterial occlusion. We included 175 patients who underwent CTP in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN). Association of CTP-derived parameters (ischemic-core volume, penumbra volume, and percentage ischemic core) with outcome was estimated with multivariable ordinal logistic regression as an adjusted odds ratio for a shift in the direction of a better outcome on the modified Rankin Scale. Interaction between CTP-derived parameters and treatment effect was determined using multivariable ordinal logistic regression. Interaction with treatment effect was also tested for mismatch (core <70 mL; penumbra core >1.2; penumbra core >10 mL). The adjusted odds ratio for improved functional outcome for ischemic core, percentage ischemic core, and penumbra were 0.79 per 10 mL (95% confidence interval: 0.71-0.89; P<0.001), 0.82 per 10% (95% confidence interval: 0.66-0.90; P=0.002), and 0.97 per 10 mL (96% confidence interval: 0.92-1.01; P=0.15), respectively. No significant interaction between any of the CTP-derived parameters and treatment effect was observed. We observed no significant interaction between mismatch and treatment effect. CTP seems useful for predicting functional outcome, but cannot reliably identify patients who will not benefit from intra-arterial therapy. © 2015 American Heart Association, Inc.
Coastal Fish Assemblages Reflect Geological and Oceanographic Gradients Within An Australian Zootone
Harvey, Euan S.; Cappo, Mike; Kendrick, Gary A.; McLean, Dianne L.
2013-01-01
Distributions of mobile animals have been shown to be heavily influenced by habitat and climate. We address the historical and contemporary context of fish habitats within a major zootone: the Recherche Archipelago, southern western Australia. Baited remote underwater video systems were set in nine habitat types within three regions to determine the species diversity and relative abundance of bony fishes, sharks and rays. Constrained ordinations and multivariate prediction and regression trees were used to examine the effects of gradients in longitude, depth, distance from islands and coast, and epibenthic habitat on fish assemblage composition. A total of 90 species from 43 families were recorded from a wide range of functional groups. Ordination accounted for 19% of the variation in the assemblage composition when constrained by spatial and epibenthic covariates, and identified redundancy in the use of distance from the nearest emergent island as a predictor. A spatial hierarchy of fourteen fish assemblages was identified using multivariate prediction and regression trees, with the primary split between assemblages on macroalgal reefs, and those on bare or sandy habitats supporting seagrass beds. The characterisation of indicator species for assemblages within the hierarchy revealed important faunal break in fish assemblages at 122.30 East at Cape Le Grand and subtle niche partitioning amongst species within the labrids and monacanthids. For example, some species of monacanthids were habitat specialists and predominantly found on seagrass (Acanthaluteres vittiger, Scobinichthys granulatus), reef (Meuschenia galii, Meuschenia hippocrepis) or sand habitats (Nelusetta ayraudi). Predatory fish that consume molluscs, crustaceans and cephalopods were dominant with evidence of habitat generalisation in reef species to cope with local disturbances by wave action. Niche separation within major genera, and a sub-regional faunal break, indicate future zootone mapping should recognise both cross-shelf and longshore environmental gradients. PMID:24278353
Schlaeger, Regina; Hardmeier, Martin; D'Souza, Marcus; Grize, Leticia; Schindler, Christian; Kappos, Ludwig; Fuhr, Peter
2016-03-01
To compare the ability of different evoked potential scores (EPS) to monitor and predict the disease course in multiple sclerosis (MS). Seventy-two patients with MS or clinically isolated syndrome were investigated by visual, motor, and somatosensory EP and expanded disability status scale (EDSS) at baseline (T0) and months 6, 12, 24, 36 (T4). EP results were rated according to ordinal (o), semi-quantitative (sq), and quantitative (q) EPS. Spearman rank correlation and multivariable linear regression were used to investigate the associations between EPS and clinical disability. All EPS correlated with EDSS cross-sectionally (0.72⩽rho⩽0.87, all p<0.001) and longitudinally (0.39⩽rho⩽0.47, all p⩽0.004). EPS(T0) and EDSS(T0) together explained 85-86% of EDSS(T4) variance. A posteriori power calculation showed that the sample sizes needed to detect significant changes over 6 months in q-EPS, sq-EPS and o-EPS with 90% certainty would be 50, 129 and 222, respectively. q-EPS change(T1-T0) correlated with EDSS change(T4-T0) (rho=0.56, p<0.001), while sq-EPS and o-EPS changes(T1-T0) did not. All three EPS allow disease course monitoring in MS. However, the quantitative EPS detects clinically relevant short-term changes with a smaller sample size than semi-quantitative or ordinal EPS. These results underscore the potential of EPS to characterize MS disease evolution. Copyright © 2016. Published by Elsevier Ireland Ltd.
Comparison of Satellite Surveying to Traditional Surveying Methods for the Resources Industry
NASA Astrophysics Data System (ADS)
Osborne, B. P.; Osborne, V. J.; Kruger, M. L.
Modern ground-based survey methods involve detailed survey, which provides three-space co-ordinates for surveyed points, to a high level of accuracy. The instruments are operated by surveyors, who process the raw results to create survey location maps for the subject of the survey. Such surveys are conducted for a location or region and referenced to the earth global co- ordinate system with global positioning system (GPS) positioning. Due to this referencing the survey is only as accurate as the GPS reference system. Satellite survey remote sensing utilise satellite imagery which have been processed using commercial geographic information system software. Three-space co-ordinate maps are generated, with an accuracy determined by the datum position accuracy and optical resolution of the satellite platform.This paper presents a case study, which compares topographic surveying undertaken by traditional survey methods with satellite surveying, for the same location. The purpose of this study is to assess the viability of satellite remote sensing for surveying in the resources industry. The case study involves a topographic survey of a dune field for a prospective mining project area in Pakistan. This site has been surveyed using modern surveying techniques and the results are compared to a satellite survey performed on the same area.Analysis of the results from traditional survey and from the satellite survey involved a comparison of the derived spatial co- ordinates from each method. In addition, comparisons have been made of costs and turnaround time for both methods.The results of this application of remote sensing is of particular interest for survey in areas with remote and extreme environments, weather extremes, political unrest, poor travel links, which are commonly associated with mining projects. Such areas frequently suffer language barriers, poor onsite technical support and resources.
Driver air bag effectiveness by severity of the crash.
Segui-Gomez, M
2000-01-01
OBJECTIVES: This analysis provided effectiveness estimates of the driver-side air bag while controlling for severity of the crash and other potential confounders. METHODS: Data were from the National Automotive Sampling System (1993-1996). Injury severity was described on the basis of the Abbreviated Injury Scale, Injury Severity Score, Functional Capacity Index, and survival. Ordinal, linear, and logistic multivariate regression methods were used. RESULTS: Air bag deployment in frontal or near-frontal crashes decreases the probability of having severe and fatal injuries (e.g., Abbreviated Injury Scale score of 4-6), including those causing a long-lasting high degree of functional limitation. However, air bag deployment in low-severity crashes increases the probability that a driver (particularly a woman) will sustain injuries of Abbreviated Injury Scale level 1 to 3. Air bag deployment exerts a net injurious effect in low-severity crashes and a net protective effect in high-severity crashes. The level of crash severity at which air bags are protective is higher for female than for male drivers. CONCLUSIONS: Air bag improvement should minimize the injuries induced by their deployment. One possibility is to raise their deployment level so that they deploy only in more severe crashes. PMID:11029991
Al-Aziz, Jameel; Christou, Nicolas; Dinov, Ivo D.
2011-01-01
The amount, complexity and provenance of data have dramatically increased in the past five years. Visualization of observed and simulated data is a critical component of any social, environmental, biomedical or scientific quest. Dynamic, exploratory and interactive visualization of multivariate data, without preprocessing by dimensionality reduction, remains a nearly insurmountable challenge. The Statistics Online Computational Resource (www.SOCR.ucla.edu) provides portable online aids for probability and statistics education, technology-based instruction and statistical computing. We have developed a new Java-based infrastructure, SOCR Motion Charts, for discovery-based exploratory analysis of multivariate data. This interactive data visualization tool enables the visualization of high-dimensional longitudinal data. SOCR Motion Charts allows mapping of ordinal, nominal and quantitative variables onto time, 2D axes, size, colors, glyphs and appearance characteristics, which facilitates the interactive display of multidimensional data. We validated this new visualization paradigm using several publicly available multivariate datasets including Ice-Thickness, Housing Prices, Consumer Price Index, and California Ozone Data. SOCR Motion Charts is designed using object-oriented programming, implemented as a Java Web-applet and is available to the entire community on the web at www.socr.ucla.edu/SOCR_MotionCharts. It can be used as an instructional tool for rendering and interrogating high-dimensional data in the classroom, as well as a research tool for exploratory data analysis. PMID:21479108
Ordinal logistic regression analysis on the nutritional status of children in KarangKitri village
NASA Astrophysics Data System (ADS)
Ohyver, Margaretha; Yongharto, Kimmy Octavian
2015-09-01
Ordinal logistic regression is a statistical technique that can be used to describe the relationship between ordinal response variable with one or more independent variables. This method has been used in various fields including in the health field. In this research, ordinal logistic regression is used to describe the relationship between nutritional status of children with age, gender, height, and family status. Nutritional status of children in this research is divided into over nutrition, well nutrition, less nutrition, and malnutrition. The purpose for this research is to describe the characteristics of children in the KarangKitri Village and to determine the factors that influence the nutritional status of children in the KarangKitri village. There are three things that obtained from this research. First, there are still children who are not categorized as well nutritional status. Second, there are children who come from sufficient economic level which include in not normal status. Third, the factors that affect the nutritional level of children are age, family status, and height.
Metrology of human-based and other qualitative measurements
NASA Astrophysics Data System (ADS)
Pendrill, Leslie; Petersson, Niclas
2016-09-01
The metrology of human-based and other qualitative measurements is in its infancy—concepts such as traceability and uncertainty are as yet poorly developed. This paper reviews how a measurement system analysis approach, particularly invoking as performance metric the ability of a probe (such as a human being) acting as a measurement instrument to make a successful decision, can enable a more general metrological treatment of qualitative observations. Measures based on human observations are typically qualitative, not only in sectors, such as health care, services and safety, where the human factor is obvious, but also in customer perception of traditional products of all kinds. A principal challenge is that the usual tools of statistics normally employed for expressing measurement accuracy and uncertainty will probably not work reliably if relations between distances on different portions of scales are not fully known, as is typical of ordinal or other qualitative measurements. A key enabling insight is to connect the treatment of decision risks associated with measurement uncertainty to generalized linear modelling (GLM). Handling qualitative observations in this way unites information theory, the perceptive identification and choice paradigms of psychophysics. The Rasch invariant measure psychometric GLM approach in particular enables a proper treatment of ordinal data; a clear separation of probe and item attribute estimates; simple expressions for instrument sensitivity; etc. Examples include two aspects of the care of breast cancer patients, from diagnosis to rehabilitation. The Rasch approach leads in turn to opportunities of establishing metrological references for quality assurance of qualitative measurements. In psychometrics, one could imagine a certified reference for knowledge challenge, for example, a particular concept in understanding physics or for product quality of a certain health care service. Multivariate methods, such as Principal Component Regression, can also be improved by exploiting the increased resolution of the Rasch approach.
Spectral distribution of solar radiation
NASA Technical Reports Server (NTRS)
Mecherikunnel, A. T.; Richmond, J.
1980-01-01
Available quantitative data on solar total and spectral irradiance are examined in the context of utilization of solar irradiance for terrestrial applications of solar energy. The extraterrestrial solar total and spectral irradiance values are also reviewed. Computed values of solar spectral irradiance at ground level for different air mass values and various levels of atmospheric pollution or turbidity are presented. Wavelengths are given for computation of solar, absorptance, transmittance and reflectance by the 100 selected-ordinate method and by the 50 selected-ordinate method for air mass 1.5 and 2 solar spectral irradiance for the four levels of atmospheric pollution.
Parallelization of PANDA discrete ordinates code using spatial decomposition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Humbert, P.
2006-07-01
We present the parallel method, based on spatial domain decomposition, implemented in the 2D and 3D versions of the discrete Ordinates code PANDA. The spatial mesh is orthogonal and the spatial domain decomposition is Cartesian. For 3D problems a 3D Cartesian domain topology is created and the parallel method is based on a domain diagonal plane ordered sweep algorithm. The parallel efficiency of the method is improved by directions and octants pipelining. The implementation of the algorithm is straightforward using MPI blocking point to point communications. The efficiency of the method is illustrated by an application to the 3D-Ext C5G7more » benchmark of the OECD/NEA. (authors)« less
A review of the matrix-exponential formalism in radiative transfer
NASA Astrophysics Data System (ADS)
Efremenko, Dmitry S.; Molina García, Víctor; Gimeno García, Sebastián; Doicu, Adrian
2017-07-01
This paper outlines the matrix exponential description of radiative transfer. The eigendecomposition method which serves as a basis for computing the matrix exponential and for representing the solution in a discrete ordinate setting is considered. The mathematical equivalence of the discrete ordinate method, the matrix operator method, and the matrix Riccati equations method is proved rigorously by means of the matrix exponential formalism. For optically thin layers, approximate solution methods relying on the Padé and Taylor series approximations to the matrix exponential, as well as on the matrix Riccati equations, are presented. For optically thick layers, the asymptotic theory with higher-order corrections is derived, and parameterizations of the asymptotic functions and constants for a water-cloud model with a Gamma size distribution are obtained.
Association of Face-lift Surgery With Social Perception, Age, Attractiveness, Health, and Success.
Nellis, Jason C; Ishii, Masaru; Papel, Ira D; Kontis, Theda C; Byrne, Patrick J; Boahene, Kofi D O; Bater, Kristin L; Ishii, Lisa E
2017-07-01
Evidence quantifying the influence of face-lift surgery on societal perceptions is lacking. To measure the association of face-lift surgery with observer-graded perceived age, attractiveness, success, and overall health. In a web-based survey, 526 casual observers naive to the purpose of the study viewed independent images of 13 unique female patient faces before or after face-lift surgery from January 1, 2016, through June 30, 2016. The Delphi method was used to select standardized patient images confirming appropriate patient candidacy and overall surgical effect. Observers estimated age and rated the attractiveness, perceived success, and perceived overall health for each patient image. Facial perception questions were answered on a visual analog scale from 0 to 100, with higher scores corresponding to more positive responses. To evaluate the accuracy of observer age estimation, the patients' preoperative estimated mean age was compared with the patients' actual mean age. A multivariate mixed-effects regression model was used to determine the effect of face-lift surgery. To further characterize the effect of face-lift surgery, estimated ordinal-rank change was calculated for each domain. Blinded casual observer ratings of patients estimated age, attractiveness, perceived success, and perceived overall health. A total of 483 observers (mean [SD] age, 29 [8.6] years; 382 women [79.4%]) successfully completed the survey. Comparing patients' preoperative estimated mean (SD) age (59.6 [9.0] years) and patients' actual mean (SD) age (58.4 [6.9] years) revealed no significant difference (t2662 = -0.47; 95% CI, -6.07 to 3.72; P = .64). On multivariate regression, patients after face-lift surgery were rated as significantly younger (coefficient, -3.69; 95% CI -4.15 to -3.23; P < .001), more attractive (coefficient, 8.21; 95% CI, 7.41-9.02; P < .001), more successful (coefficient, 5.82; 95% CI, 5.05 to 6.59; P < .001), and overall healthier (coefficient, 8.72; 95% CI, 7.88-9.56; P < .001). The ordinal rank changes for an average individual were -21 for perceived age, 21 for attractiveness, 16 for success, and 21 for overall health. In this study, observer perceptions of face-lift surgery were associated with views that patients appeared younger, more attractive, healthier, and more successful. These findings highlight observer perceptions of face-lift surgery that could positively influence social interactions. NA.
Analysis of noise-induced temporal correlations in neuronal spike sequences
NASA Astrophysics Data System (ADS)
Reinoso, José A.; Torrent, M. C.; Masoller, Cristina
2016-11-01
We investigate temporal correlations in sequences of noise-induced neuronal spikes, using a symbolic method of time-series analysis. We focus on the sequence of time-intervals between consecutive spikes (inter-spike-intervals, ISIs). The analysis method, known as ordinal analysis, transforms the ISI sequence into a sequence of ordinal patterns (OPs), which are defined in terms of the relative ordering of consecutive ISIs. The ISI sequences are obtained from extensive simulations of two neuron models (FitzHugh-Nagumo, FHN, and integrate-and-fire, IF), with correlated noise. We find that, as the noise strength increases, temporal order gradually emerges, revealed by the existence of more frequent ordinal patterns in the ISI sequence. While in the FHN model the most frequent OP depends on the noise strength, in the IF model it is independent of the noise strength. In both models, the correlation time of the noise affects the OP probabilities but does not modify the most probable pattern.
Phospholipid Fatty Acid Analysis: Past, Present and Future
NASA Astrophysics Data System (ADS)
Findlay, R. H.
2008-12-01
With their 1980 publication, Bobbie and White initiated the use of phospholipid fatty acids for the study of microbial communities. This method, integrated with a previously published biomass assay based on the colorimetric detection of orthophosphate liberated from phospholipids, provided the first quantitative method for determining microbial community structure. The method is based on a quantitative extraction of lipids from the sample matrix, isolation of the phospholipids, conversion of the phospholipid fatty acids to their corresponding fatty acid methyl esters (known by the acronym FAME) and the separation, identification and quantification of the FAME by gas chromatography. Early laboratory and field samples focused on correlating individual fatty acids to particular groups of microorganisms. Subsequent improvements to the methodology include reduced solvent volumes for extractions, improved sensitivity in the detection of orthophosphate and the use of solid phase extraction technology. Improvements in the field of gas chromatography also increased accessibility of the technique and it has been widely applied to water, sediment, soil and aerosol samples. Whole cell fatty acid analysis, a related but not equal technique, is currently used for phenotypic characterization in bacterial species descriptions and is the basis for a commercial, rapid bacterial identification system. In the early 1990ês application of multivariate statistical analysis, first cluster analysis and then principal component analysis, further improved the usefulness of the technique and allowed the development of a functional group approach to interpretation of phospholipid fatty acid profiles. Statistical techniques currently applied to the analysis of phospholipid fatty acid profiles include constrained ordinations and neutral networks. Using redundancy analysis, a form of constrained ordination, we have recently shown that both cation concentration and dissolved organic matter (DOM) quality are determinates of microbial community structure in forested headwater streams. One of the most exciting recent developments in phospholipid fatty acid analysis is the application of compound specific stable isotope analysis. We are currently applying this technique to stream sediments to help determine which microorganisms are involved in the initial processing of DOM and the technique promises to be a useful tool for assigning ecological function to microbial populations.
Glantz, S; Wilson-Loots, R
2003-01-01
Background: Because it is widely played, claims that smoking restrictions will adversely affect bingo games is used as an argument against these policies. We used publicly available data from Massachusetts to assess the impact of 100% smoke-free ordinances on profits from bingo and other gambling sponsored by charitable organisations between 1985 and 2001. Methods: We conducted two analyses: (1) a general linear model implementation of a time series analysis with net profits (adjusted to 2001 dollars) as the dependent variable, and community (as a fixed effect), year, lagged net profits, and the length of time the ordinance had been in force as the independent variables; (2) multiple linear regression of total state profits against time, lagged profits, and the percentage of the entire state population in communities that allow charitable gaming but prohibit smoking. Results: The general linear model analysis of data from individual communities showed that, while adjusted profits fell over time, this effect was not related to the presence of an ordinance. The analysis in terms of the fraction of the population living in communities with ordinances yielded the same result. Conclusion: Policymakers can implement smoke-free policies without concern that these policies will affect charitable gaming. PMID:14660778
Optimizing the maximum reported cluster size in the spatial scan statistic for ordinal data.
Kim, Sehwi; Jung, Inkyung
2017-01-01
The spatial scan statistic is an important tool for spatial cluster detection. There have been numerous studies on scanning window shapes. However, little research has been done on the maximum scanning window size or maximum reported cluster size. Recently, Han et al. proposed to use the Gini coefficient to optimize the maximum reported cluster size. However, the method has been developed and evaluated only for the Poisson model. We adopt the Gini coefficient to be applicable to the spatial scan statistic for ordinal data to determine the optimal maximum reported cluster size. Through a simulation study and application to a real data example, we evaluate the performance of the proposed approach. With some sophisticated modification, the Gini coefficient can be effectively employed for the ordinal model. The Gini coefficient most often picked the optimal maximum reported cluster sizes that were the same as or smaller than the true cluster sizes with very high accuracy. It seems that we can obtain a more refined collection of clusters by using the Gini coefficient. The Gini coefficient developed specifically for the ordinal model can be useful for optimizing the maximum reported cluster size for ordinal data and helpful for properly and informatively discovering cluster patterns.
Optimizing the maximum reported cluster size in the spatial scan statistic for ordinal data
Kim, Sehwi
2017-01-01
The spatial scan statistic is an important tool for spatial cluster detection. There have been numerous studies on scanning window shapes. However, little research has been done on the maximum scanning window size or maximum reported cluster size. Recently, Han et al. proposed to use the Gini coefficient to optimize the maximum reported cluster size. However, the method has been developed and evaluated only for the Poisson model. We adopt the Gini coefficient to be applicable to the spatial scan statistic for ordinal data to determine the optimal maximum reported cluster size. Through a simulation study and application to a real data example, we evaluate the performance of the proposed approach. With some sophisticated modification, the Gini coefficient can be effectively employed for the ordinal model. The Gini coefficient most often picked the optimal maximum reported cluster sizes that were the same as or smaller than the true cluster sizes with very high accuracy. It seems that we can obtain a more refined collection of clusters by using the Gini coefficient. The Gini coefficient developed specifically for the ordinal model can be useful for optimizing the maximum reported cluster size for ordinal data and helpful for properly and informatively discovering cluster patterns. PMID:28753674
Evaluation of redundancy analysis to identify signatures of local adaptation.
Capblancq, Thibaut; Luu, Keurcien; Blum, Michael G B; Bazin, Eric
2018-05-26
Ordination is a common tool in ecology that aims at representing complex biological information in a reduced space. In landscape genetics, ordination methods such as principal component analysis (PCA) have been used to detect adaptive variation based on genomic data. Taking advantage of environmental data in addition to genotype data, redundancy analysis (RDA) is another ordination approach that is useful to detect adaptive variation. This paper aims at proposing a test statistic based on RDA to search for loci under selection. We compare redundancy analysis to pcadapt, which is a nonconstrained ordination method, and to a latent factor mixed model (LFMM), which is a univariate genotype-environment association method. Individual-based simulations identify evolutionary scenarios where RDA genome scans have a greater statistical power than genome scans based on PCA. By constraining the analysis with environmental variables, RDA performs better than PCA in identifying adaptive variation when selection gradients are weakly correlated with population structure. Additionally, we show that if RDA and LFMM have a similar power to identify genetic markers associated with environmental variables, the RDA-based procedure has the advantage to identify the main selective gradients as a combination of environmental variables. To give a concrete illustration of RDA in population genomics, we apply this method to the detection of outliers and selective gradients on an SNP data set of Populus trichocarpa (Geraldes et al., 2013). The RDA-based approach identifies the main selective gradient contrasting southern and coastal populations to northern and continental populations in the northwestern American coast. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Pisegna, Jessica M; Kaneoka, Asako; Leonard, Rebecca; Langmore, Susan E
2018-02-01
The goal of this work was to better understand perceptual judgments of pharyngeal residue on flexible endoscopic evaluation of swallowing (FEES) and the influence of a visual analog scale (VAS) versus an ordinal scale on clinician ratings. The intent was to determine if perceptual judgments of residue were more accurately described by equal or unequal intervals. Thirty-three speech language pathologists rated pharyngeal residue from 75 FEES videos representing a wide range of residue severities for thin liquid, applesauce, and cracker boluses. Clinicians rated their impression of the overall residue amount in each video on a VAS and, in a different session, on a five-point ordinal scale. Residue ratings were made in two separate sessions separated by several weeks. Statistical correlations of the two rating methods were carried out and best-fit models were determined for each bolus type. A total of 2475 VAS ratings and 2473 ordinal ratings were collected. Residue ratings from both methods (VAS and ordinal) were strongly correlated for all bolus types. The best fit for the data was a quadratic model representing unequal intervals, which significantly improved the r 2 values for each bolus type (cracker r 2 = 0.98, applesauce r 2 = 0.99, thin liquid r 2 = 0.98, all p < 0.0001). Perceptual ratings of pharyngeal residue demonstrated a statistical relationship consistent with unequal intervals. The present findings support the use of a VAS to rate residue on FEES, allowing for greater precision as compared to traditional ordinal rating scales. Perceptual judgments of pharyngeal residue reflected unequal intervals, an important concept that should be considered in future rating scales.
Diet and proinflammatory cytokine levels in head and neck squamous cell carcinoma
Arthur, Anna E.; Peterson, Karen E.; Shen, Jincheng; Djuric, Zora; Taylor, Jeremy M.G.; Hebert, James R.; Duffy, Sonia A.; Peterson, Lisa A.; Bellile, Emily L.; Whitfield, Joel R.; Chepeha, Douglas B.; Schipper, Matthew J.; Wolf, Gregory T.; Rozek, Laura S.
2014-01-01
Background Proinflammatory cytokine levels may be associated with cancer stage, recurrence, and survival. A study was undertaken to determine if cytokine levels were associated with dietary patterns and fat-soluble micronutrients in previously untreated head and neck squamous cell carcinoma (HNSCC) patients. Methods This was a cross-sectional study of 160 newly diagnosed HNSCC patients who completed pretreatment food frequency questionnaires (FFQ) and health surveys. Dietary patterns were derived from FFQs using principal component analysis. Pretreatment serum levels of the proinflammatory cytokines IL-6, TNF-α, and IFN-γ were measured by ELISA and serum carotenoid and tocopherol levels by HPLC. Multivariable ordinal logistic regression models examined associations between cytokines and quartiles of reported and serum dietary variables. Results Three dietary patterns emerged: whole foods, Western, and convenience foods. In multivariable analyses, higher whole foods pattern scores were significantly associated with lower levels of IL-6, TNF-α, and IFN-γ (P = <0.001, P = 0.008, and P = 0.03, respectively). Significant inverse associations were reported between IL-6, TNF-α, and IFN-γ levels and quartiles of total reported carotenoid intake (P = 0.006, P = 0.04, and P = 0.04, respectively). There was an inverse association between IFN-γ levels and serum α-tocopherol levels (P = 0.03). Conclusions Consuming a pretreatment diet rich in vegetables, fruit, fish, poultry and whole grains may be associated with lower proinflammatory cytokine levels in patients with HNSCC. PMID:24830761
NASA Technical Reports Server (NTRS)
Yang, Qiguang; Liu, Xu; Wu, Wan; Kizer, Susan; Baize, Rosemary R.
2016-01-01
A hybrid stream PCRTM-SOLAR model has been proposed for fast and accurate radiative transfer simulation. It calculates the reflected solar (RS) radiances with a fast coarse way and then, with the help of a pre-saved matrix, transforms the results to obtain the desired high accurate RS spectrum. The methodology has been demonstrated with the hybrid stream discrete ordinate (HSDO) radiative transfer (RT) model. The HSDO method calculates the monochromatic radiances using a 4-stream discrete ordinate method, where only a small number of monochromatic radiances are simulated with both 4-stream and a larger N-stream (N = 16) discrete ordinate RT algorithm. The accuracy of the obtained channel radiance is comparable to the result from N-stream moderate resolution atmospheric transmission version 5 (MODTRAN5). The root-mean-square errors are usually less than 5x10(exp -4) mW/sq cm/sr/cm. The computational speed is three to four-orders of magnitude faster than the medium speed correlated-k option MODTRAN5. This method is very efficient to simulate thousands of RS spectra under multi-layer clouds/aerosols and solar radiation conditions for climate change study and numerical weather prediction applications.
Nixon, M; Mahmoud, L; Glantz, S
2004-01-01
Background: The tobacco industry uses claims of state preemption or violations of the US Constitution in litigation to overturn local tobacco control ordinances. Methods: Collection of lawsuits filed or threatened against local governments in the USA; review of previously secret tobacco industry documents; interviews with key informants. Results: The industry is most likely to prevail when a court holds that there is explicit preemption language by the state legislature to exclusively regulate tobacco. The industry has a much weaker record on claims of implied preemption and has lost all challenges brought under equal protection claims in the cases we located. Although the tobacco industry is willing to spend substantial amounts of money on these lawsuits, it never won on constitutional equal protection grounds and lost or dropped 60% (16/27) of the cases it brought claiming implied state preemption. Conclusions: Municipalities should continue to pass ordinances and be prepared to defend them against claims of implied preemption or on constitutional grounds. If the ordinance is properly prepared they will likely prevail. Health advocates should be prepared to assist in this process. PMID:14985600
Processing Ordinality and Quantity: The Case of Developmental Dyscalculia
Rubinsten, Orly; Sury, Dana
2011-01-01
In contrast to quantity processing, up to date, the nature of ordinality has received little attention from researchers despite the fact that both quantity and ordinality are embodied in numerical information. Here we ask if there are two separate core systems that lie at the foundations of numerical cognition: (1) the traditionally and well accepted numerical magnitude system but also (2) core system for representing ordinal information. We report two novel experiments of ordinal processing that explored the relation between ordinal and numerical information processing in typically developing adults and adults with developmental dyscalculia (DD). Participants made “ordered” or “non-ordered” judgments about 3 groups of dots (non-symbolic numerical stimuli; in Experiment 1) and 3 numbers (symbolic task: Experiment 2). In contrast to previous findings and arguments about quantity deficit in DD participants, when quantity and ordinality are dissociated (as in the current tasks), DD participants exhibited a normal ratio effect in the non-symbolic ordinal task. They did not show, however, the ordinality effect. Ordinality effect in DD appeared only when area and density were randomized, but only in the descending direction. In the symbolic task, the ordinality effect was modulated by ratio and direction in both groups. These findings suggest that there might be two separate cognitive representations of ordinal and quantity information and that linguistic knowledge may facilitate estimation of ordinal information. PMID:21935374
Processing ordinality and quantity: the case of developmental dyscalculia.
Rubinsten, Orly; Sury, Dana
2011-01-01
In contrast to quantity processing, up to date, the nature of ordinality has received little attention from researchers despite the fact that both quantity and ordinality are embodied in numerical information. Here we ask if there are two separate core systems that lie at the foundations of numerical cognition: (1) the traditionally and well accepted numerical magnitude system but also (2) core system for representing ordinal information. We report two novel experiments of ordinal processing that explored the relation between ordinal and numerical information processing in typically developing adults and adults with developmental dyscalculia (DD). Participants made "ordered" or "non-ordered" judgments about 3 groups of dots (non-symbolic numerical stimuli; in Experiment 1) and 3 numbers (symbolic task: Experiment 2). In contrast to previous findings and arguments about quantity deficit in DD participants, when quantity and ordinality are dissociated (as in the current tasks), DD participants exhibited a normal ratio effect in the non-symbolic ordinal task. They did not show, however, the ordinality effect. Ordinality effect in DD appeared only when area and density were randomized, but only in the descending direction. In the symbolic task, the ordinality effect was modulated by ratio and direction in both groups. These findings suggest that there might be two separate cognitive representations of ordinal and quantity information and that linguistic knowledge may facilitate estimation of ordinal information.
Underage alcohol policies across 50 California cities: an assessment of best practices
2012-01-01
Background We pursue two primary goals in this article: (1) to test a methodology and develop a dataset on U.S. local-level alcohol policy ordinances, and (2) to evaluate the presence, comprehensiveness, and stringency of eight local alcohol policies in 50 diverse California cities in relationship to recommended best practices in both public health literature and governmental recommendations to reduce underage drinking. Methods Following best practice recommendations from a wide array of authoritative sources, we selected eight local alcohol policy topics (e.g., conditional use permits, responsible beverage service training, social host ordinances, window/billboard advertising ordinances), and determined the presence or absence as well as the stringency (restrictiveness) and comprehensiveness (number of provisions) of each ordinance in each of the 50 cities in 2009. Following the alcohol policy literature, we created scores for each city on each type of ordinance and its associated components. We used these data to evaluate the extent to which recommendations for best practices to reduce underage alcohol use are being followed. Results (1) Compiling datasets of local-level alcohol policy laws and their comprehensiveness and stringency is achievable, even absent comprehensive, on-line, or other legal research tools. (2) We find that, with some exceptions, most of the 50 cities do not have high scores for presence, comprehensiveness, or stringency across the eight key policies. Critical policies such as responsible beverage service and deemed approved ordinances are uncommon, and, when present, they are generally neither comprehensive nor stringent. Even within policies that have higher adoption rates, central elements are missing across many or most cities’ ordinances. Conclusion This study demonstrates the viability of original legal data collection in the U.S. pertaining to local ordinances and of creating quantitative scores for each policy type to reflect comprehensiveness and stringency. Analysis of the resulting dataset reveals that, although the 50 cities have taken important steps to improve public health with regard to underage alcohol use and abuse, there is a great deal more that needs to be done to bring these cities into compliance with best practice recommendations. PMID:22734468
NASA Technical Reports Server (NTRS)
Kato, S.; Smith, G. L.; Barker, H. W.
2001-01-01
An algorithm is developed for the gamma-weighted discrete ordinate two-stream approximation that computes profiles of domain-averaged shortwave irradiances for horizontally inhomogeneous cloudy atmospheres. The algorithm assumes that frequency distributions of cloud optical depth at unresolved scales can be represented by a gamma distribution though it neglects net horizontal transport of radiation. This algorithm is an alternative to the one used in earlier studies that adopted the adding method. At present, only overcast cloudy layers are permitted.
Kelley, Mary E.; Anderson, Stewart J.
2008-01-01
Summary The aim of the paper is to produce a methodology that will allow users of ordinal scale data to more accurately model the distribution of ordinal outcomes in which some subjects are susceptible to exhibiting the response and some are not (i.e., the dependent variable exhibits zero inflation). This situation occurs with ordinal scales in which there is an anchor that represents the absence of the symptom or activity, such as “none”, “never” or “normal”, and is particularly common when measuring abnormal behavior, symptoms, and side effects. Due to the unusually large number of zeros, traditional statistical tests of association can be non-informative. We propose a mixture model for ordinal data with a built-in probability of non-response that allows modeling of the range (e.g., severity) of the scale, while simultaneously modeling the presence/absence of the symptom. Simulations show that the model is well behaved and a likelihood ratio test can be used to choose between the zero-inflated and the traditional proportional odds model. The model, however, does have minor restrictions on the nature of the covariates that must be satisfied in order for the model to be identifiable. The method is particularly relevant for public health research such as large epidemiological surveys where more careful documentation of the reasons for response may be difficult. PMID:18351711
Chaisinanunkul, Napasri; Adeoye, Opeolu; Lewis, Roger J.; Grotta, James C.; Broderick, Joseph; Jovin, Tudor G.; Nogueira, Raul G.; Elm, Jordan; Graves, Todd; Berry, Scott; Lees, Kennedy R.; Barreto, Andrew D.; Saver, Jeffrey L.
2015-01-01
Background and Purpose Although the modified Rankin Scale (mRS) is the most commonly employed primary endpoint in acute stroke trials, its power is limited when analyzed in dichotomized fashion and its indication of effect size challenging to interpret when analyzed ordinally. Weighting the seven Rankin levels by utilities may improve scale interpretability while preserving statistical power. Methods A utility weighted mRS (UW-mRS) was derived by averaging values from time-tradeoff (patient centered) and person-tradeoff (clinician centered) studies. The UW-mRS, standard ordinal mRS, and dichotomized mRS were applied to 11 trials or meta-analyses of acute stroke treatments, including lytic, endovascular reperfusion, blood pressure moderation, and hemicraniectomy interventions. Results Utility values were: mRS 0–1.0; mRS 1 - 0.91; mRS 2 - 0.76; mRS 3 - 0.65; mRS 4 - 0.33; mRS 5 & 6 - 0. For trials with unidirectional treatment effects, the UW-mRS paralleled the ordinal mRS and outperformed dichotomous mRS analyses. Both the UW-mRS and the ordinal mRS were statistically significant in six of eight unidirectional effect trials, while dichotomous analyses were statistically significant in two to four of eight. In bidirectional effect trials, both the UW-mRS and ordinal tests captured the divergent treatment effects by showing neutral results whereas some dichotomized analyses showed positive results. Mean utility differences in trials with statistically significant positive results ranged from 0.026 to 0.249. Conclusion A utility-weighted mRS performs similarly to the standard ordinal mRS in detecting treatment effects in actual stroke trials and ensures the quantitative outcome is a valid reflection of patient-centered benefits. PMID:26138130
FDDO and DSMC analyses of rarefied gas flow through 2D nozzles
NASA Technical Reports Server (NTRS)
Chung, Chan-Hong; De Witt, Kenneth J.; Jeng, Duen-Ren; Penko, Paul F.
1992-01-01
Two different approaches, the finite-difference method coupled with the discrete-ordinate method (FDDO), and the direct-simulation Monte Carlo (DSMC) method, are used in the analysis of the flow of a rarefied gas expanding through a two-dimensional nozzle and into a surrounding low-density environment. In the FDDO analysis, by employing the discrete-ordinate method, the Boltzmann equation simplified by a model collision integral is transformed to a set of partial differential equations which are continuous in physical space but are point functions in molecular velocity space. The set of partial differential equations are solved by means of a finite-difference approximation. In the DSMC analysis, the variable hard sphere model is used as a molecular model and the no time counter method is employed as a collision sampling technique. The results of both the FDDO and the DSMC methods show good agreement. The FDDO method requires less computational effort than the DSMC method by factors of 10 to 40 in CPU time, depending on the degree of rarefaction.
NASA Technical Reports Server (NTRS)
Weng, Fuzhong
1992-01-01
A theory is developed for discretizing the vector integro-differential radiative transfer equation including both solar and thermal radiation. A complete solution and boundary equations are obtained using the discrete-ordinate method. An efficient numerical procedure is presented for calculating the phase matrix and achieving computational stability. With natural light used as a beam source, the Stokes parameters from the model proposed here are compared with the analytical solutions of Chandrasekhar (1960) for a Rayleigh scattering atmosphere. The model is then applied to microwave frequencies with a thermal source, and the brightness temperatures are compared with those from Stamnes'(1988) radiative transfer model.
Forcino, Frank L; Leighton, Lindsey R; Twerdy, Pamela; Cahill, James F
2015-01-01
Community ecologists commonly perform multivariate techniques (e.g., ordination, cluster analysis) to assess patterns and gradients of taxonomic variation. A critical requirement for a meaningful statistical analysis is accurate information on the taxa found within an ecological sample. However, oversampling (too many individuals counted per sample) also comes at a cost, particularly for ecological systems in which identification and quantification is substantially more resource consuming than the field expedition itself. In such systems, an increasingly larger sample size will eventually result in diminishing returns in improving any pattern or gradient revealed by the data, but will also lead to continually increasing costs. Here, we examine 396 datasets: 44 previously published and 352 created datasets. Using meta-analytic and simulation-based approaches, the research within the present paper seeks (1) to determine minimal sample sizes required to produce robust multivariate statistical results when conducting abundance-based, community ecology research. Furthermore, we seek (2) to determine the dataset parameters (i.e., evenness, number of taxa, number of samples) that require larger sample sizes, regardless of resource availability. We found that in the 44 previously published and the 220 created datasets with randomly chosen abundances, a conservative estimate of a sample size of 58 produced the same multivariate results as all larger sample sizes. However, this minimal number varies as a function of evenness, where increased evenness resulted in increased minimal sample sizes. Sample sizes as small as 58 individuals are sufficient for a broad range of multivariate abundance-based research. In cases when resource availability is the limiting factor for conducting a project (e.g., small university, time to conduct the research project), statistically viable results can still be obtained with less of an investment.
Cooke, Andrew L; Diaz-Abele, Julian; Hayakawa, Tom; Buchel, Ed; Dalke, Kimberly; Lambert, Pascal
2017-09-01
To determine whether adjuvant radiation therapy (RT) is associated with adverse patient-reported outcomes and surgical complications 1 year after skin-sparing mastectomy and immediate autologous free flap reconstruction for breast cancer. We compared 24 domains of patient-reported outcome measures 1 year after autologous reconstruction between patients who received adjuvant RT and those who did not. A total of 125 patients who underwent surgery between 2012 and 2015 at our institution were included from the Mastectomy Reconstruction Outcomes Consortium study database. Adjusted multivariate models were created incorporating RT technical data, age, cancer stage, estrogen receptor, chemotherapy, breast size, body mass index, and income to determine whether RT was associated with outcomes. At 1 year after surgery, European Organisation for Research and Treatment of Cancer (EORTC) Breast Cancer-Specific Quality of Life Questionnaire breast symptoms were significantly greater in 64 patients who received RT (8-point difference on 100-point ordinal scale, P<.0001) versus 61 who did not receive RT in univariate and multivariate models. EORTC arm symptoms (20-point difference on 100-point ordinal scale, P=.0200) differed on univariate analysis but not on multivariate analysis. All other outcomes-including Numerical Pain Rating Scale, BREAST-Q (Post-operative Reconstruction Module), Patient-Report Outcomes Measurement Information System Profile 29, McGill Pain Questionnaire-Short Form (MPQ-SF) score, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire-were not statistically different between groups. Surgical complications were uncommon and did not differ by treatment. RT to the neo-breast compared with no RT following immediate autologous free flap reconstruction for breast cancer is well tolerated at 1 year following surgery despite patients undergoing RT also having a higher cancer stage and more intensive surgical and systemic treatment. Neo-breast symptoms are more common in patients receiving RT by the EORTC Breast Cancer-Specific Quality of Life Questionnaire but not by the BREAST-Q. Patient-reported results at 1 year after surgery suggest RT following immediate autologous free flap breast reconstruction is well tolerated. Copyright © 2017 Elsevier Inc. All rights reserved.
Numerical simulation of rarefied gas flow through a slit
NASA Technical Reports Server (NTRS)
Keith, Theo G., Jr.; Jeng, Duen-Ren; De Witt, Kenneth J.; Chung, Chan-Hong
1990-01-01
Two different approaches, the finite-difference method coupled with the discrete-ordinate method (FDDO), and the direct-simulation Monte Carlo (DSMC) method, are used in the analysis of the flow of a rarefied gas from one reservoir to another through a two-dimensional slit. The cases considered are for hard vacuum downstream pressure, finite pressure ratios, and isobaric pressure with thermal diffusion, which are not well established in spite of the simplicity of the flow field. In the FDDO analysis, by employing the discrete-ordinate method, the Boltzmann equation simplified by a model collision integral is transformed to a set of partial differential equations which are continuous in physical space but are point functions in molecular velocity space. The set of partial differential equations are solved by means of a finite-difference approximation. In the DSMC analysis, three kinds of collision sampling techniques, the time counter (TC) method, the null collision (NC) method, and the no time counter (NTC) method, are used.
Sylvester, Peter T.; Evans, John A.; Zipfel, Gregory J.; Chole, Richard A.; Uppaluri, Ravindra; Haughey, Bruce H.; Getz, Anne E.; Silverstein, Julie; Rich, Keith M.; Kim, Albert H.; Dacey, Ralph G.
2014-01-01
Purpose The clinical benefit of combined intraoperative magnetic resonance imaging (iMRI) and endoscopy for transsphenoidal pituitary adenoma resection has not been completely characterized. This study assessed the impact of microscopy, endoscopy, and/or iMRI on progression-free survival, extent of resection status (gross-, near-, and subtotal resection), and operative complications. Methods Retrospective analyses were performed on 446 transsphenoidal pituitary adenoma surgeries at a single institution between 1998 and 2012. Multivariate analyses were used to control for baseline characteristics, differences during extent of resection status, and progression-free survival analysis. Results Additional surgery was performed after iMRI in 56/156 cases (35.9 %), which led to increased extent of resection status in 15/156 cases (9.6 %). Multivariate ordinal logistic regression revealed no increase in extent of resection status following iMRI or endoscopy alone; however, combining these modalities increased extent of resection status (odds ratio 2.05, 95 % CI 1.21–3.46) compared to conventional transsphenoidal microsurgery. Multivariate Cox regression revealed that reduced extent of resection status shortened progression-free survival for near- versus gross-total resection [hazard ratio (HR) 2.87, 95 % CI 1.24–6.65] and sub- versus near-total resection (HR 2.10; 95 % CI 1.00–4.40). Complication comparisons between microscopy, endoscopy, and iMRI revealed increased perioperative deaths for endoscopy versus microscopy (4/209 and 0/237, respectively), but this difference was non-significant considering multiple post hoc comparisons (Fisher exact, p = 0.24). Conclusions Combined use of endoscopy and iMRI increased pituitary adenoma extent of resection status compared to conventional transsphenoidal microsurgery, and increased extent of resection status was associated with longer progression-free survival. Treatment modality combination did not significantly impact complication rate. PMID:24599833
2010-01-01
Background The primary aim of this study was to develop and psychometrically test a Greek-language instrument for measuring satisfaction with home care. The first empirical evidence about the level of satisfaction with these services in Greece is also provided. Methods The questionnaire resulted from literature search, on-site observation and cognitive interviews. It was applied in 2006 to a sample of 201 enrollees of five home care programs in the city of Thessaloniki and contains 31 items that measure satisfaction with individual service attributes and are expressed on a 5-point Likert scale. The latter has been usually considered in practice as an interval scale, although it is in principle ordinal. We thus treated the variable as an ordinal one, but also employed the traditional approach in order to compare the findings. Our analysis was therefore based on ordinal measures such as the polychoric correlation, Kendall's Tau b coefficient and ordinal Cronbach's alpha. Exploratory factor analysis was followed by an assessment of internal consistency reliability, test-retest reliability, construct validity and sensitivity. Results Analyses with ordinal and interval scale measures produced in essence very similar results and identified four multi-item scales. Three of these were found to be reliable and valid: socioeconomic change, staff skills and attitudes and service appropriateness. A fourth dimension -service planning- had lower internal consistency reliability and yet very satisfactory test-retest reliability, construct validity and floor and ceiling effects. The global satisfaction scale created was also quite reliable. Overall, participants were satisfied -yet not very satisfied- with home care services. More room for improvement seems to exist for the socio-economic and planning aspects of care and less for staff skills and attitudes and appropriateness of provided services. Conclusions The methods developed seem to be a promising tool for the measurement of home care satisfaction in Greece. PMID:20602759
A single camera roentgen stereophotogrammetry method for static displacement analysis.
Gussekloo, S W; Janssen, B A; George Vosselman, M; Bout, R G
2000-06-01
A new method to quantify motion or deformation of bony structures has been developed, since quantification is often difficult due to overlaying tissue, and the currently used roentgen stereophotogrammetry method requires significant investment. In our method, a single stationary roentgen source is used, as opposed to the usual two, which, in combination with a fixed radiogram cassette holder, forms a camera with constant interior orientation. By rotating the experimental object, it is possible to achieve a sufficient angle between the various viewing directions, enabling photogrammetric calculations. The photogrammetric procedure was performed on digitised radiograms and involved template matching to increase accuracy. Co-ordinates of spherical markers in the head of a bird (Rhea americana), were calculated with an accuracy of 0.12mm. When these co-ordinates were used in a deformation analysis, relocations of about 0.5mm could be accurately determined.
Two-dimensional HID light source radiative transfer using discrete ordinates method
NASA Astrophysics Data System (ADS)
Ghrib, Basma; Bouaoun, Mohamed; Elloumi, Hatem
2016-08-01
This paper shows the implementation of the Discrete Ordinates Method for handling radiation problems in High Intensity Discharge (HID) lamps. Therefore, we start with presenting this rigorous method for treatment of radiation transfer in a two-dimensional, axisymmetric HID lamp. Furthermore, the finite volume method is used for the spatial discretization of the Radiative Transfer Equation. The atom and electron densities were calculated using temperature profiles established by a 2D semi-implicit finite-element scheme for the solution of conservation equations relative to energy, momentum, and mass. Spectral intensities as a function of position and direction are first calculated, and then axial and radial radiative fluxes are evaluated as well as the net emission coefficient. The results are given for a HID mercury lamp on a line-by-line basis. A particular attention is paid on the 253.7 nm resonance and 546.1 nm green lines.
Causal analysis of ordinal treatments and binary outcomes under truncation by death.
Wang, Linbo; Richardson, Thomas S; Zhou, Xiao-Hua
2017-06-01
It is common that in multi-arm randomized trials, the outcome of interest is "truncated by death," meaning that it is only observed or well-defined conditioning on an intermediate outcome. In this case, in addition to pairwise contrasts, the joint inference for all treatment arms is also of interest. Under a monotonicity assumption we present methods for both pairwise and joint causal analyses of ordinal treatments and binary outcomes in presence of truncation by death. We illustrate via examples the appropriateness of our assumptions in different scientific contexts.
An approach to solve group-decision-making problems with ordinal interval numbers.
Fan, Zhi-Ping; Liu, Yang
2010-10-01
The ordinal interval number is a form of uncertain preference information in group decision making (GDM), while it is seldom discussed in the existing research. This paper investigates how the ranking order of alternatives is determined based on preference information of ordinal interval numbers in GDM problems. When ranking a large quantity of ordinal interval numbers, the efficiency and accuracy of the ranking process are critical. A new approach is proposed to rank alternatives using ordinal interval numbers when every ranking ordinal in an ordinal interval number is thought to be uniformly and independently distributed in its interval. First, we give the definition of possibility degree on comparing two ordinal interval numbers and the related theory analysis. Then, to rank alternatives, by comparing multiple ordinal interval numbers, a collective expectation possibility degree matrix on pairwise comparisons of alternatives is built, and an optimization model based on this matrix is constructed. Furthermore, an algorithm is also presented to rank alternatives by solving the model. Finally, two examples are used to illustrate the use of the proposed approach.
City curfew ordinances and teenage motor vehicle injury.
Preusser, D F; Williams, A F; Lund, A K; Zador, P L
1990-08-01
Several U.S. cities have curfew ordinances that limit the late night activities of minor teenagers in public places including highways. Detroit, Cleveland, and Columbus, which have curfew ordinances, were compared to Cincinnati, which does not have such an ordinance. The curfew ordinances were associated with a 23% reduction in motor vehicle related injury for 13- to 17-year-olds as passengers, drivers, pedestrians, or bicyclists during the curfew hours. It was concluded that city curfew ordinances, like the statewide driving curfews studied in other states, can reduce motor vehicle injury to teenagers during the particularly hazardous late night hours.
Gap-minimal systems of notations and the constructible hierarchy
NASA Technical Reports Server (NTRS)
Lucian, M. L.
1972-01-01
If a constructibly countable ordinal alpha is a gap ordinal, then the order type of the set of index ordinals smaller than alpha is exactly alpha. The gap ordinals are the only points of discontinuity of a certain ordinal-valued function. The notion of gap minimality for well ordered systems of notations is defined, and the existence of gap-minimal systems of notations of arbitrarily large constructibly countable length is established.
GPU accelerated simulations of 3D deterministic particle transport using discrete ordinates method
NASA Astrophysics Data System (ADS)
Gong, Chunye; Liu, Jie; Chi, Lihua; Huang, Haowei; Fang, Jingyue; Gong, Zhenghu
2011-07-01
Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, inhomogeneous Boltzmann transport equation. The numerical solution to the Boltzmann equation involves the discrete ordinates ( Sn) method and the procedure of source iteration. In this paper, we present a GPU accelerated simulation of one energy group time-independent deterministic discrete ordinates particle transport in 3D Cartesian geometry (Sweep3D). The performance of the GPU simulations are reported with the simulations of vacuum boundary condition. The discussion of the relative advantages and disadvantages of the GPU implementation, the simulation on multi GPUs, the programming effort and code portability are also reported. The results show that the overall performance speedup of one NVIDIA Tesla M2050 GPU ranges from 2.56 compared with one Intel Xeon X5670 chip to 8.14 compared with one Intel Core Q6600 chip for no flux fixup. The simulation with flux fixup on one M2050 is 1.23 times faster than on one X5670.
78 FR 54670 - Miami Tribe of Oklahoma-Liquor Control Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-05
... Tribe of Oklahoma--Liquor Control Ordinance AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice. SUMMARY: This notice publishes the Miami Tribe of Oklahoma--Liquor Control Ordinance. This Ordinance... Oklahoma, increases the ability of the tribal government to control the distribution and possession of...
75 FR 65373 - Klamath Tribes Liquor Control Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-22
... DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs Klamath Tribes Liquor Control Ordinance AGENCY... certification of the amendment to the Klamath Tribes Liquor Control Ordinance. The first Ordinance was published... and controls the sale, possession and distribution of liquor within the tribal lands. The tribal lands...
Ordinal probability effect measures for group comparisons in multinomial cumulative link models.
Agresti, Alan; Kateri, Maria
2017-03-01
We consider simple ordinal model-based probability effect measures for comparing distributions of two groups, adjusted for explanatory variables. An "ordinal superiority" measure summarizes the probability that an observation from one distribution falls above an independent observation from the other distribution, adjusted for explanatory variables in a model. The measure applies directly to normal linear models and to a normal latent variable model for ordinal response variables. It equals Φ(β/2) for the corresponding ordinal model that applies a probit link function to cumulative multinomial probabilities, for standard normal cdf Φ and effect β that is the coefficient of the group indicator variable. For the more general latent variable model for ordinal responses that corresponds to a linear model with other possible error distributions and corresponding link functions for cumulative multinomial probabilities, the ordinal superiority measure equals exp(β)/[1+exp(β)] with the log-log link and equals approximately exp(β/2)/[1+exp(β/2)] with the logit link, where β is the group effect. Another ordinal superiority measure generalizes the difference of proportions from binary to ordinal responses. We also present related measures directly for ordinal models for the observed response that need not assume corresponding latent response models. We present confidence intervals for the measures and illustrate with an example. © 2016, The International Biometric Society.
Implicitly causality enforced solution of multidimensional transient photon transport equation.
Handapangoda, Chintha C; Premaratne, Malin
2009-12-21
A novel method for solving the multidimensional transient photon transport equation for laser pulse propagation in biological tissue is presented. A Laguerre expansion is used to represent the time dependency of the incident short pulse. Owing to the intrinsic causal nature of Laguerre functions, our technique automatically always preserve the causality constrains of the transient signal. This expansion of the radiance using a Laguerre basis transforms the transient photon transport equation to the steady state version. The resulting equations are solved using the discrete ordinates method, using a finite volume approach. Therefore, our method enables one to handle general anisotropic, inhomogeneous media using a single formulation but with an added degree of flexibility owing to the ability to invoke higher-order approximations of discrete ordinate quadrature sets. Therefore, compared with existing strategies, this method offers the advantage of representing the intensity with a high accuracy thus minimizing numerical dispersion and false propagation errors. The application of the method to one, two and three dimensional geometries is provided.
Linearized radiative transfer models for retrieval of cloud parameters from EPIC/DSCOVR measurements
NASA Astrophysics Data System (ADS)
Molina García, Víctor; Sasi, Sruthy; Efremenko, Dmitry S.; Doicu, Adrian; Loyola, Diego
2018-07-01
In this paper, we describe several linearized radiative transfer models which can be used for the retrieval of cloud parameters from EPIC (Earth Polychromatic Imaging Camera) measurements. The approaches under examination are (1) the linearized forward approach, represented in this paper by the linearized discrete ordinate and matrix operator methods with matrix exponential, and (2) the forward-adjoint approach based on the discrete ordinate method with matrix exponential. To enhance the performance of the radiative transfer computations, the correlated k-distribution method and the Principal Component Analysis (PCA) technique are used. We provide a compact description of the proposed methods, as well as a numerical analysis of their accuracy and efficiency when simulating EPIC measurements in the oxygen A-band channel at 764 nm. We found that the computation time of the forward-adjoint approach using the correlated k-distribution method in conjunction with PCA is approximately 13 s for simultaneously computing the derivatives with respect to cloud optical thickness and cloud top height.
NASA Astrophysics Data System (ADS)
Rahman, Inayat Ur; Khan, Nasrullah; Ali, Kishwar
2017-04-01
An understory vegetation survey of the Pinus wallichiana-dominated temperate forests of Swat District was carried out to inspect the structure, composition and ecological associations of the forest vegetation. A quadrat method of sampling was used to record the floristic and phytosociological data necessary for the analysis using 300 quadrats of 10 × 10 m each. Some vegetation parameters viz. frequency and density for trees (overstory vegetation) as well as for the understory vegetation were recorded. The results revealed that in total, 92 species belonging to 77 different genera and 45 families existed in the area. The largest families were Asteraceae, Rosaceae and Lamiaceae with 12, ten and nine species, respectively. Ward's agglomerative cluster analysis for tree species resulted in three floristically and ecologically distinct community types along different topographic and soil variables. Importance value indices (IVI) were also calculated for understory vegetation and were subjected to ordination techniques, i.e. canonical correspondence analysis (CCA) and detrended correspondence analysis (DCA). DCA bi-plots for stands show that most of the stands were scattered around the centre of the DCA bi-plot, identified by two slightly scattered clusters. DCA for species bi-plot clearly identified three clusters of species revealing three types of understory communities in the study area. Results of the CCA were somewhat different from the DCA showing the impact of environmental variables on the understory species. CCA results reveal that three environmental variables, i.e. altitude, slope and P (mg/kg), have a strong influence on distribution of stands and species. Impact of tree species on the understory vegetation was also tested by CCA which showed that four tree species, i.e. P. wallichiana A.B. Jackson, Juglans regia Linn., Quercus dilatata Lindl. ex Royle and Cedrus deodara (Roxb. ex Lamb.) G. Don, have strong influences on associated understory vegetation. It is therefore concluded that Swat District has various microclimatic zones with suitable environmental variables to support distinct flora.
Vleeshouwers, Jolien; Knardahl, Stein; Christensen, Jan Olav
2016-01-01
Study Objectives: This prospective cohort study examined previously underexplored relations between psychological/social work factors and troubled sleep in order to provide practical information about specific, modifiable factors at work. Methods: A comprehensive evaluation of a range of psychological/social work factors was obtained by several designs; i.e., cross-sectional analyses at baseline and follow-up, prospective analyses with baseline predictors (T1), prospective analyses with average exposure across waves as predictor ([T1 + T2] / 2), and prospective analyses with change in exposure from baseline to follow-up as predictor. Participants consisted of a sample of Norwegian employees from a broad spectrum of occupations, who completed a questionnaire at two points in time, approximately two years apart. Cross-sectional analyses at T1 comprised 7,459 participants, cross-sectional analyses at T2 included 6,688 participants. Prospective analyses comprised a sample 5,070 of participants who responded at both T1 and T2. Univariable and multivariable ordinal logistic regressions were performed. Results: Thirteen psychological/social work factors and two aspects of troubled sleep, namely difficulties initiating sleep and disturbed sleep, were studied. Ordinal logistic regressions revealed statistically significant associations for all psychological and social work factors in at least one of the analyses. Psychological and social work factors predicted sleep problems in the short term as well as the long term. Conclusions: All work factors investigated showed statistically significant associations with both sleep items, however quantitative job demands, decision control, role conflict, and support from superior were the most robust predictors and may therefore be suitable targets of interventions aimed at improving employee sleep. Citation: Vleeshouwers J, Knardahl S, Christensen JO. Effects of psychological and social work factors on self-reported sleep disturbance and difficulties initiating sleep. SLEEP 2016;39(4):833–846. PMID:26446114
Augmenting the Deliberative Method for Ranking Risks.
Susel, Irving; Lasley, Trace; Montezemolo, Mark; Piper, Joel
2016-01-01
The Department of Homeland Security (DHS) characterized and prioritized the physical cross-border threats and hazards to the nation stemming from terrorism, market-driven illicit flows of people and goods (illegal immigration, narcotics, funds, counterfeits, and weaponry), and other nonmarket concerns (movement of diseases, pests, and invasive species). These threats and hazards pose a wide diversity of consequences with very different combinations of magnitudes and likelihoods, making it very challenging to prioritize them. This article presents the approach that was used at DHS to arrive at a consensus regarding the threats and hazards that stand out from the rest based on the overall risk they pose. Due to time constraints for the decision analysis, it was not feasible to apply multiattribute methodologies like multiattribute utility theory or the analytic hierarchy process. Using a holistic approach was considered, such as the deliberative method for ranking risks first published in this journal. However, an ordinal ranking alone does not indicate relative or absolute magnitude differences among the risks. Therefore, the use of the deliberative method for ranking risks is not sufficient for deciding whether there is a material difference between the top-ranked and bottom-ranked risks, let alone deciding what the stand-out risks are. To address this limitation of ordinal rankings, the deliberative method for ranking risks was augmented by adding an additional step to transform the ordinal ranking into a ratio scale ranking. This additional step enabled the selection of stand-out risks to help prioritize further analysis. © 2015 Society for Risk Analysis.
Ordinality and the nature of symbolic numbers.
Lyons, Ian M; Beilock, Sian L
2013-10-23
The view that representations of symbolic and nonsymbolic numbers are closely tied to one another is widespread. However, the link between symbolic and nonsymbolic numbers is almost always inferred from cardinal processing tasks. In the current work, we show that considering ordinality instead points to striking differences between symbolic and nonsymbolic numbers. Human behavioral and neural data show that ordinal processing of symbolic numbers (Are three Indo-Arabic numerals in numerical order?) is distinct from symbolic cardinal processing (Which of two numerals represents the greater quantity?) and nonsymbolic number processing (ordinal and cardinal judgments of dot-arrays). Behaviorally, distance-effects were reversed when assessing ordinality in symbolic numbers, but canonical distance-effects were observed for cardinal judgments of symbolic numbers and all nonsymbolic judgments. At the neural level, symbolic number-ordering was the only numerical task that did not show number-specific activity (greater than control) in the intraparietal sulcus. Only activity in left premotor cortex was specifically associated with symbolic number-ordering. For nonsymbolic numbers, activation in cognitive-control areas during ordinal processing and a high degree of overlap between ordinal and cardinal processing networks indicate that nonsymbolic ordinality is assessed via iterative cardinality judgments. This contrasts with a striking lack of neural overlap between ordinal and cardinal judgments anywhere in the brain for symbolic numbers, suggesting that symbolic number processing varies substantially with computational context. Ordinal processing sheds light on key differences between symbolic and nonsymbolic number processing both behaviorally and in the brain. Ordinality may prove important for understanding the power of representing numbers symbolically.
Social Host Ordinances and Policies. Prevention Update
ERIC Educational Resources Information Center
Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2011
2011-01-01
Social host liability laws (also known as teen party ordinances, loud or unruly gathering ordinances, or response costs ordinances) target the location in which underage drinking takes place. Social host liability laws hold noncommercial individuals responsible for underage drinking events on property they own, lease, or otherwise control. They…
25 CFR 522.8 - Publication of class III ordinance and approval.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Section 522.8 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.8 Publication of class III ordinance and approval. The Chairman shall publish a class III tribal gaming...
27 CFR 478.24 - Compilation of State laws and published ordinances.
Code of Federal Regulations, 2010 CFR
2010-04-01
... and published ordinances. 478.24 Section 478.24 Alcohol, Tobacco Products, and Firearms BUREAU OF... published ordinances. (a) The Director shall annually revise and furnish Federal firearms licensees with a compilation of State laws and published ordinances which are relevant to the enforcement of this part. The...
Eckler, Petya; Rodgers, Shelly; Everett, Kevin
2016-10-01
To answer the call for more systematic surveillance, analysis and evaluation of tobacco news coverage, a 6-year content analysis of newspaper stories from Missouri was conducted to evaluate the presence of public health facts and characteristics of stories framed for or against tobacco control. The method was a content analysis of all Missouri newspapers (N = 381) from September 2006 to November 2011 for a total sample of 4711. Results were connected to the larger, societal context within which newspaper stories reside, i.e., towns that passed or did not pass a smoke-free ordinance during the project intervention. Results showed the majority of news stories were about tobacco control, which were mostly written at the local level, were episodic, and carried a positive slant toward tobacco control. However, there were more negative than positive headlines, and more negative editorials than non-editorials. Tobacco control stories used fewer public health facts than non-tobacco control stories. Towns with existing smoke-free ordinances had more tobacco control stories, and towns without smoke-free ordinances had fewer tobacco control stories and more non-tobacco control stories, suggesting a connection between news media coverage and the passage of smoke-free policies. We conclude that the tobacco industry may have had success in impacting news stories in no-ordinance cities by diverting attention from tobacco control to secondary topics, such as youth smoking, which meant stories had fewer public health facts and fewer positive health benefits in towns that may have needed these details most.
A Framework to Reduce Infectious Disease Risk from Urban Poultry in the United States
Tobin, Molly R.; Goldshear, Jesse L.; Price, Lance B.; Graham, Jay P.
2015-01-01
Objectives Backyard poultry ownership is increasingly common in U.S. cities and is regulated at the local level. Human contact with live poultry is a well-known risk for infection with zoonotic pathogens, notably Salmonella, yet the ability of local jurisdictions to reduce the risk of infectious disease transmission from poultry to humans is unstudied. We reviewed urban poultry ordinances in the United States and reported Salmonella outbreaks from backyard poultry to identify regulatory gaps in preventing zoonotic pathogen transmission. Based on this analysis, we propose regulatory guidelines for U.S. cities to reduce infectious disease risk from backyard poultry ownership. Methods We assessed local ordinances in the 150 most populous U.S. jurisdictions for content related to noncommercial poultry ownership using online resources and communications with government officials. We also performed a literature review using publicly available data sources to identify human infectious disease outbreaks caused by contact with backyard poultry. Results Of the cities reviewed, 93% (n=139) permit poultry in some capacity. Most urban poultry ordinances share common characteristics focused on reducing nuisance to neighbors. Ordinances do not address many pathways of transmission relevant to poultry-to-human transmission of pathogens, such as manure management. Conclusions To reduce the risk of pathogen exposure from backyard poultry, urban ordinances should incorporate the following seven components: limited flock size, composting of manure in sealed containers, prohibition of slaughter, required veterinary care to sick birds, appropriate disposal of dead birds, annual permits linked to consumer education, and a registry of poultry owners. PMID:26346104
Local co-ordination and case management can enhance Indigenous eye care – a qualitative study
2013-01-01
Background Indigenous adults suffer six times more blindness than other Australians but 94% of this vision loss is unnecessary being preventable or treatable. We have explored the barriers and solutions to improve Indigenous eye health and proposed significant system changes required to close the gap for Indigenous eye health. This paper aims to identify the local co-ordination and case management requirements necessary to improve eye care for Indigenous Australians. Methods A qualitative study, using semi-structured interviews, focus groups, stakeholder workshops and meetings was conducted in community, private practice, hospital, non-government organisation and government settings. Data were collected at 21 sites across Australia. Semi-structured interviews were conducted with 289 people working in Indigenous health and eye care; focus group discussions with 81 community members; stakeholder workshops involving 86 individuals; and separate meetings with 75 people. 531 people participated in the consultations. Barriers and issues were identified through thematic analysis and policy solutions developed through iterative consultation. Results Poorly co-ordinated eye care services for Indigenous Australians are inefficient and costly and result in poorer outcomes for patients, communities and health care providers. Services are more effective where there is good co-ordination of services and case management of patients along the pathway of care. The establishment of clear pathways of care, development local and regional partnerships to manage services and service providers and the application of sufficient workforce with clear roles and responsibilities have the potential to achieve important improvements in eye care. Conclusions Co-ordination is a key to close the gap in eye care for Indigenous Australians. Properly co-ordinated care and support along the patient pathway through case management will save money by preventing dropout of patients who haven’t received treatment and a successfully functioning system will encourage more people to enter for care. PMID:23822115
Finite element, modal co-ordinate analysis of structures subjected to moving loads
NASA Astrophysics Data System (ADS)
Olsson, M.
1985-03-01
Some of the possibilities of the finite element method in the moving load problem are demonstrated. The bridge-vehicle interaction phenomenon is considered by deriving a general bridge-vehicle element which is believed to be novel. This element may be regarded as a finite element with time-dependent and unsymmetric element matrices. The bridge response is formulated in modal co-ordinates thereby reducing the number of equations to be solved within each time step. Illustrative examples are shown for the special case of a beam bridge model and a one-axle vehicle model.
Weed vegetation ecology of arable land in Salalah, Southern Oman.
El-Sheikh, Mohamed A
2013-07-01
This paper applies multivariate statistical methods to a data set of weed relevés from arable fields in two different habitat types of coastal and mountainous escarpments in Southern Oman. The objectives were to test the effect of environmental gradients, crop plants and time on weed species composition, to rank the importance of these particular factors, and to describe the patterns of species composition and diversity associated with these factors. Through the application of TWINSPAN, DCA and CCA programs on data relating to 102 species recorded in 28 plots and farms distributed in the study area, six plant communities were identified: I- Dichanthium micranthum, II- Cynodon dactylon-D. micranthum, III- Convolvulus arvensis, IV- C. dactylon-Sonchus oleraceus, V- Amaranthus viridis and VI- Suaeda aegyptiaca-Achyranthes aspera. The ordination process (CCA) provided a sequence of plant communities and species diversity that correlated with some anthropogenic factors, physiographic variables and crop types. Therefore, length of time since farm construction, disturbance levels and altitude are the most important factors related to the occurrence of the species. The perennial species correlated with the more degraded mountain areas of new farm stands, whereas most of the annuals correlated with old lowland and less disturbed farms.
Weed vegetation ecology of arable land in Salalah, Southern Oman
El-Sheikh, Mohamed A.
2013-01-01
This paper applies multivariate statistical methods to a data set of weed relevés from arable fields in two different habitat types of coastal and mountainous escarpments in Southern Oman. The objectives were to test the effect of environmental gradients, crop plants and time on weed species composition, to rank the importance of these particular factors, and to describe the patterns of species composition and diversity associated with these factors. Through the application of TWINSPAN, DCA and CCA programs on data relating to 102 species recorded in 28 plots and farms distributed in the study area, six plant communities were identified: I- Dichanthium micranthum, II- Cynodon dactylon–D. micranthum, III- Convolvulus arvensis, IV- C. dactylon–Sonchus oleraceus, V- Amaranthus viridis and VI- Suaeda aegyptiaca–Achyranthes aspera. The ordination process (CCA) provided a sequence of plant communities and species diversity that correlated with some anthropogenic factors, physiographic variables and crop types. Therefore, length of time since farm construction, disturbance levels and altitude are the most important factors related to the occurrence of the species. The perennial species correlated with the more degraded mountain areas of new farm stands, whereas most of the annuals correlated with old lowland and less disturbed farms. PMID:23961246
Functional traits, convergent evolution, and periodic tables of niches.
Winemiller, Kirk O; Fitzgerald, Daniel B; Bower, Luke M; Pianka, Eric R
2015-08-01
Ecology is often said to lack general theories sufficiently predictive for applications. Here, we examine the concept of a periodic table of niches and feasibility of niche classification schemes from functional trait and performance data. Niche differences and their influence on ecological patterns and processes could be revealed effectively by first performing data reduction/ordination analyses separately on matrices of trait and performance data compiled according to logical associations with five basic niche 'dimensions', or aspects: habitat, life history, trophic, defence and metabolic. Resultant patterns then are integrated to produce interpretable niche gradients, ordinations and classifications. Degree of scheme periodicity would depend on degrees of niche conservatism and convergence causing species clustering across multiple niche dimensions. We analysed a sample data set containing trait and performance data to contrast two approaches for producing niche schemes: species ordination within niche gradient space, and niche categorisation according to trait-value thresholds. Creation of niche schemes useful for advancing ecological knowledge and its applications will depend on research that produces functional trait and performance datasets directly related to niche dimensions along with criteria for data standardisation and quality. As larger databases are compiled, opportunities will emerge to explore new methods for data reduction, ordination and classification. © 2015 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.
Media advocacy, tobacco control policy change and teen smoking in Florida
Niederdeppe, Jeff; Farrelly, Matthew C; Wenter, Dana
2007-01-01
Objective To assess whether media advocacy activities implemented by the Florida Tobacco Control Program contributed to increased news coverage, policy changes and reductions in youth smoking. Methods A content analysis of news coverage appearing in Florida newspapers between 22 April 1998 and 31 December 2001 was conducted, and patterns of coverage before and after the implementation of media advocacy efforts to promote tobacco product placement ordinances were compared. Event history analysis was used to assess whether news coverage increased the probability of enacting these ordinances in 23 of 67 Florida counties and ordinary least square (OLS) regression was used to gauge the effect of these policies on changes in youth smoking prevalence. Results The volume of programme‐related news coverage decreased after the onset of media advocacy efforts, but the ratio of coverage about Students Working Against Tobacco (the Florida Tobacco Control Program's youth advocacy organisation) relative to other topics increased. News coverage contributed to the passage of tobacco product placement ordinances in Florida counties, but these ordinances did not lead to reduced youth smoking. Conclusion This study adds to the growing literature supporting the use of media advocacy as a tool to change health‐related policies. However, results suggest caution in choosing policy goals that may or may not influence health behaviour. PMID:17297073
Minkler, Meredith; Estrada, Jessica; Thayer, Ryan; Juachon, Lisa; Wakimoto, Patricia; Falbe, Jennifer
2018-04-09
In urban "food swamps" like San Francisco's Tenderloin, the absence of full-service grocery stores and plethora of corner stores saturated with tobacco, alcohol, and processed food contribute to high rates of chronic disease. We explore the genesis of the Tenderloin Healthy Corner Store Coalition, its relationship with health department and academic partners, and its contributions to the passage and implementation of a healthy retail ordinance through community-based participatory research (CBPR), capacity building, and advocacy. The healthy retail ordinance incentivizes small stores to increase space for healthy foods and decrease tobacco and alcohol availability. Through Yin's multi-method case study analysis, we examined the partnership's processes and contributions to the ordinance within the framework of Kingdon's three-stage policymaking model. We also assessed preliminary outcomes of the ordinance, including a 35% increase in produce sales and moderate declines in tobacco sales in the first four stores participating in the Tenderloin, as well as a "ripple effect," through which non-participating stores also improved their retail environments. Despite challenges, CBPR partnerships led by a strong community coalition concerned with bedrock issues like food justice and neighborhood inequities in tobacco exposure may represent an important avenue for health equity-focused research and its translation into practice.
Using ordinal partition transition networks to analyze ECG data
NASA Astrophysics Data System (ADS)
Kulp, Christopher W.; Chobot, Jeremy M.; Freitas, Helena R.; Sprechini, Gene D.
2016-07-01
Electrocardiogram (ECG) data from patients with a variety of heart conditions are studied using ordinal pattern partition networks. The ordinal pattern partition networks are formed from the ECG time series by symbolizing the data into ordinal patterns. The ordinal patterns form the nodes of the network and edges are defined through the time ordering of the ordinal patterns in the symbolized time series. A network measure, called the mean degree, is computed from each time series-generated network. In addition, the entropy and number of non-occurring ordinal patterns (NFP) is computed for each series. The distribution of mean degrees, entropies, and NFPs for each heart condition studied is compared. A statistically significant difference between healthy patients and several groups of unhealthy patients with varying heart conditions is found for the distributions of the mean degrees, unlike for any of the distributions of the entropies or NFPs.
Influences of gender and socioeconomic status on the motor proficiency of children in the UK.
Morley, David; Till, Kevin; Ogilvie, Paul; Turner, Graham
2015-12-01
As the development of movement skills are so crucial to a child's involvement in lifelong physical activity and sport, the purpose of this study was to assess the motor proficiency of children aged 4-7 years (range=4.3-7.2 years), whilst considering gender and socioeconomic status. 369 children (176 females, 193 males, aged=5.96 ± 0.57 years) were assessed for fine motor precision, fine motor integration, manual dexterity, bilateral co-ordination, balance, speed and agility, upper-limb co-ordination and strength. The average standard score for all participants was 44.4 ± 8.9, classifying the participants towards the lower end of the average score. Multivariate analysis of covariance identified significant effects for gender (p<0.001) and socioeconomic status (p<0.001). Females outperformed males for fine motor skills and boys outperformed girls for catch and dribble gross motor skills. High socioeconomic status significantly outperformed middle and/or low socioeconomic status for total, fine and gross motor proficiency. Current motor proficiency of primary children aged 4-7 years in the UK is just below average with differences evident between gender and socioeconomic status. Teachers and sport coaches working with primary aged children should concentrate on the development of movement skills, whilst considering differences between genders and socioeconomic status. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Goal-based h-adaptivity of the 1-D diamond difference discrete ordinate method
NASA Astrophysics Data System (ADS)
Jeffers, R. S.; Kópházi, J.; Eaton, M. D.; Févotte, F.; Hülsemann, F.; Ragusa, J.
2017-04-01
The quantity of interest (QoI) associated with a solution of a partial differential equation (PDE) is not, in general, the solution itself, but a functional of the solution. Dual weighted residual (DWR) error estimators are one way of providing an estimate of the error in the QoI resulting from the discretisation of the PDE. This paper aims to provide an estimate of the error in the QoI due to the spatial discretisation, where the discretisation scheme being used is the diamond difference (DD) method in space and discrete ordinate (SN) method in angle. The QoI are reaction rates in detectors and the value of the eigenvalue (Keff) for 1-D fixed source and eigenvalue (Keff criticality) neutron transport problems respectively. Local values of the DWR over individual cells are used as error indicators for goal-based mesh refinement, which aims to give an optimal mesh for a given QoI.
Radiative transfer models for retrieval of cloud parameters from EPIC/DSCOVR measurements
NASA Astrophysics Data System (ADS)
Molina García, Víctor; Sasi, Sruthy; Efremenko, Dmitry S.; Doicu, Adrian; Loyola, Diego
2018-07-01
In this paper we analyze the accuracy and efficiency of several radiative transfer models for inferring cloud parameters from radiances measured by the Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR). The radiative transfer models are the exact discrete ordinate and matrix operator methods with matrix exponential, and the approximate asymptotic and equivalent Lambertian cloud models. To deal with the computationally expensive radiative transfer calculations, several acceleration techniques such as, for example, the telescoping technique, the method of false discrete ordinate, the correlated k-distribution method and the principal component analysis (PCA) are used. We found that, for the EPIC oxygen A-band absorption channel at 764 nm, the exact models using the correlated k-distribution in conjunction with PCA yield an accuracy better than 1.5% and a computation time of 18 s for radiance calculations at 5 viewing zenith angles.
75 FR 51102 - Liquor Ordinance of the Wichita and Affiliated Tribes; Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-18
... Tribes; Correction AGENCY: Bureau of Indian Affairs, Interior ACTION: Notice; correction SUMMARY: The... Liquor Ordinance of the Wichita and Affiliated Tribes. The notice refers to an amended ordinance of the Wichita and Affiliated Tribes when in fact the Liquor Ordinance adopted by Resolution No. WT-10-31 on May...
ERIC Educational Resources Information Center
Gadermann, Anne M.; Guhn, Martin; Zumbo, Bruno D.
2012-01-01
This paper provides a conceptual, empirical, and practical guide for estimating ordinal reliability coefficients for ordinal item response data (also referred to as Likert, Likert-type, ordered categorical, or rating scale item responses). Conventionally, reliability coefficients, such as Cronbach's alpha, are calculated using a Pearson…
Ordinal measures for iris recognition.
Sun, Zhenan; Tan, Tieniu
2009-12-01
Images of a human iris contain rich texture information useful for identity authentication. A key and still open issue in iris recognition is how best to represent such textural information using a compact set of features (iris features). In this paper, we propose using ordinal measures for iris feature representation with the objective of characterizing qualitative relationships between iris regions rather than precise measurements of iris image structures. Such a representation may lose some image-specific information, but it achieves a good trade-off between distinctiveness and robustness. We show that ordinal measures are intrinsic features of iris patterns and largely invariant to illumination changes. Moreover, compactness and low computational complexity of ordinal measures enable highly efficient iris recognition. Ordinal measures are a general concept useful for image analysis and many variants can be derived for ordinal feature extraction. In this paper, we develop multilobe differential filters to compute ordinal measures with flexible intralobe and interlobe parameters such as location, scale, orientation, and distance. Experimental results on three public iris image databases demonstrate the effectiveness of the proposed ordinal feature models.
Solutions to Some Nonlinear Equations from Nonmetric Data.
ERIC Educational Resources Information Center
Rule, Stanley J.
1979-01-01
A method to provide estimates of parameters of specified nonlinear equations from ordinal data generated from a crossed design is presented. The statistical basis for the method, called NOPE (nonmetric parameter estimation), as well as examples using artifical data, are presented. (Author/JKS)
Food marketing to children through toys: response of restaurants to the first U.S. toy ordinance.
Otten, Jennifer J; Hekler, Eric B; Krukowski, Rebecca A; Buman, Matthew P; Saelens, Brian E; Gardner, Christopher D; King, Abby C
2012-01-01
On August 9, 2010, Santa Clara County CA became the first U.S. jurisdiction to implement an ordinance that prohibits the distribution of toys and other incentives to children in conjunction with meals, foods, or beverages that do not meet minimal nutritional criteria. Restaurants had many different options for complying with this ordinance, such as introducing more healthful menu options, reformulating current menu items, or changing marketing or toy distribution practices. To assess how ordinance-affected restaurants changed their child menus, marketing, and toy distribution practices relative to non-affected restaurants. Children's menu items and child-directed marketing and toy distribution practices were examined before and at two time points after ordinance implementation (from July through November 2010) at ordinance-affected fast-food restaurants compared with demographically matched unaffected same-chain restaurants using the Children's Menu Assessment tool. Affected restaurants showed a 2.8- to 3.4-fold improvement in Children's Menu Assessment scores from pre- to post-ordinance with minimal changes at unaffected restaurants. Response to the ordinance varied by restaurant. Improvements were seen in on-site nutritional guidance; promotion of healthy meals, beverages, and side items; and toy marketing and distribution activities. The ordinance appears to have positively influenced marketing of healthful menu items and toys as well as toy distribution practices at ordinance-affected restaurants, but did not affect the number of healthful food items offered. Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ebert, Martin A., E-mail: Martin.Ebert@health.wa.gov.au; School of Physics, University of Western Australia, Perth, Western Australia; Foo, Kerwyn
Purpose: To use a high-quality multicenter trial dataset to determine dose-volume effects for gastrointestinal (GI) toxicity following radiation therapy for prostate carcinoma. Influential dose-volume histogram regions were to be determined as functions of dose, anatomical location, toxicity, and clinical endpoint. Methods and Materials: Planning datasets for 754 participants in the TROG 03.04 RADAR trial were available, with Late Effects of Normal Tissues (LENT) Subjective, Objective, Management, and Analytic (SOMA) toxicity assessment to a median of 72 months. A rank sum method was used to define dose-volume cut-points as near-continuous functions of dose to 3 GI anatomical regions, together with amore » comprehensive assessment of significance. Univariate and multivariate ordinal regression was used to assess the importance of cut-points at each dose. Results: Dose ranges providing significant cut-points tended to be consistent with those showing significant univariate regression odds-ratios (representing the probability of a unitary increase in toxicity grade per percent relative volume). Ranges of significant cut-points for rectal bleeding validated previously published results. Separation of the lower GI anatomy into complete anorectum, rectum, and anal canal showed the impact of mid-low doses to the anal canal on urgency and tenesmus, completeness of evacuation and stool frequency, and mid-high doses to the anorectum on bleeding and stool frequency. Derived multivariate models emphasized the importance of the high-dose region of the anorectum and rectum for rectal bleeding and mid- to low-dose regions for diarrhea and urgency and tenesmus, and low-to-mid doses to the anal canal for stool frequency, diarrhea, evacuation, and bleeding. Conclusions: Results confirm anatomical dependence of specific GI toxicities. They provide an atlas summarizing dose-histogram effects and derived constraints as functions of anatomical region, dose, toxicity, and endpoint for informing future radiation therapy planning.« less
25 CFR 522.7 - Disapproval of a class III ordinance.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Disapproval of a class III ordinance. 522.7 Section 522.7 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.7 Disapproval of a class III...
25 CFR 522.5 - Disapproval of a class II ordinance.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Disapproval of a class II ordinance. 522.5 Section 522.5 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.5 Disapproval of a class II...
Ordinary Least Squares Estimation of Parameters in Exploratory Factor Analysis with Ordinal Data
ERIC Educational Resources Information Center
Lee, Chun-Ting; Zhang, Guangjian; Edwards, Michael C.
2012-01-01
Exploratory factor analysis (EFA) is often conducted with ordinal data (e.g., items with 5-point responses) in the social and behavioral sciences. These ordinal variables are often treated as if they were continuous in practice. An alternative strategy is to assume that a normally distributed continuous variable underlies each ordinal variable.…
Local Area Co-Ordination: Strengthening Support for People with Learning Disabilities in Scotland
ERIC Educational Resources Information Center
Stalker, Kirsten Ogilvie; Malloch, Margaret; Barry, Monica Anne; Watson, June Ann
2008-01-01
This paper reports the findings of a study commissioned by the Scottish Executive which examined the introduction and implementation of local area co-ordination (LAC) in Scotland. A questionnaire about their posts was completed by 44 local area co-ordinators, interviews were conducted with 35 local area co-ordinators and 14 managers and case…
NASA Astrophysics Data System (ADS)
Zhang, Wei; Wang, Jun
2018-05-01
A novel nonlinear stochastic interacting price dynamics is proposed and investigated by the bond percolation on Sierpinski gasket fractal-like lattice, aim to make a new approach to reproduce and study the complexity dynamics of real security markets. Fractal-like lattices correspond to finite graphs with vertices and edges, which are similar to fractals, and Sierpinski gasket is a well-known example of fractals. Fractional ordinal array entropy and fractional ordinal array complexity are introduced to analyze the complexity behaviors of financial signals. To deeper comprehend the fluctuation characteristics of the stochastic price evolution, the complexity analysis of random logarithmic returns and volatility are preformed, including power-law distribution, fractional sample entropy and fractional ordinal array complexity. For further verifying the rationality and validity of the developed stochastic price evolution, the actual security market dataset are also studied with the same statistical methods for comparison. The empirical results show that this stochastic price dynamics can reconstruct complexity behaviors of the actual security markets to some extent.
Discrete ordinates solutions of nongray radiative transfer with diffusely reflecting walls
NASA Technical Reports Server (NTRS)
Menart, J. A.; Lee, Haeok S.; Kim, Tae-Kuk
1993-01-01
Nongray gas radiation in a plane parallel slab bounded by gray, diffusely reflecting walls is studied using the discrete ordinates method. The spectral equation of transfer is averaged over a narrow wavenumber interval preserving the spectral correlation effect. The governing equations are derived by considering the history of multiple reflections between two reflecting wails. A closure approximation is applied so that only a finite number of reflections have to be explicitly included. The closure solutions express the physics of the problem to a very high degree and show relatively little error. Numerical solutions are obtained by applying a statistical narrow-band model for gas properties and a discrete ordinates code. The net radiative wail heat fluxes and the radiative source distributions are obtained for different temperature profiles. A zeroth-degree formulation, where no wall reflection is handled explicitly, is sufficient to predict the radiative transfer accurately for most cases considered, when compared with increasingly accurate solutions based on explicitly tracing a larger number of wail reflections without any closure approximation applied.
Tourism and hotel revenues before and after passage of smoke-free restaurant ordinances.
Glantz, S A; Charlesworth, A
1999-05-26
Claims that ordinances requiring smoke-free restaurants will adversely affect tourism have been used to argue against passing such ordinances. Data exist regarding the validity of these claims. To determine the changes in hotel revenues and international tourism after passage of smoke-free restaurant ordinances in locales where the effect has been debated. Comparison of hotel revenues and tourism rates before and after passage of 100% smoke-free restaurant ordinances and comparison with US hotel revenue overall. Three states (California, Utah, and Vermont) and 6 cities (Boulder, Colo; Flagstaff, Ariz; Los Angeles, Calif; Mesa, Ariz; New York, NY; and San Francisco, Calif) in which the effect on tourism of smoke-free restaurant ordinances had been debated. Hotel room revenues and hotel revenues as a fraction of total retail sales compared with preordinance revenues and overall US revenues. In constant 1997 dollars, passage of the smoke-free restaurant ordinance was associated with a statistically significant increase in the rate of change of hotel revenues in 4 localities, no significant change in 4 localities, and a significant slowing in the rate of increase (but not a decrease) in 1 locality. There was no significant change in the rate of change of hotel revenues as a fraction of total retail sales (P=.16) or total US hotel revenues associated with the ordinances when pooled across all localities (P = .93). International tourism was either unaffected or increased following implementation of the smoke-free ordinances. Smoke-free ordinances do not appear to adversely affect, and may increase, tourist business.
Co-ordinated action between youth-care and sports: facilitators and barriers.
Hermens, Niels; de Langen, Lisanne; Verkooijen, Kirsten T; Koelen, Maria A
2017-07-01
In the Netherlands, youth-care organisations and community sports clubs are collaborating to increase socially vulnerable youths' participation in sport. This is rooted in the idea that sports clubs are settings for youth development. As not much is known about co-ordinated action involving professional care organisations and community sports clubs, this study aims to generate insight into facilitators of and barriers to successful co-ordinated action between these two organisations. A cross-sectional study was conducted using in-depth semi-structured qualitative interview data. In total, 23 interviews were held at five locations where co-ordinated action between youth-care and sports takes place. Interviewees were youth-care workers, representatives from community sports clubs, and Care Sport Connectors who were assigned to encourage and manage the co-ordinated action. Using inductive coding procedures, this study shows that existing and good relationships, a boundary spanner, care workers' attitudes, knowledge and competences of the participants, organisational policies and ambitions, and some elements external to the co-ordinated action were reported to be facilitators or barriers. In addition, the participants reported that the different facilitators and barriers influenced the success of the co-ordinated action at different stages of the co-ordinated action. Future research is recommended to further explore the role of boundary spanners in co-ordinated action involving social care organisations and community sports clubs, and to identify what external elements (e.g. events, processes, national policies) are turning points in the formation, implementation and continuation of such co-ordinated action. © 2017 John Wiley & Sons Ltd.
Structure, function and five basic needs of the global health research system
Rudan, Igor; Sridhar, Devi
2016-01-01
Background Two major initiatives that were set up to support and co–ordinate global health research efforts have been largely discontinued in recent years: the Global Forum for Health Research and World Health Organization's Department for Research Policy and Cooperation. These developments provide an interesting case study into the factors that contribute to the sustainability of initiatives to support and co–ordinate global health research in the 21st century. Methods We reviewed the history of attempts to govern, support or co–ordinate research in global health. Moreover, we studied the changes and shifts in funding flows attributed to global health research. This allowed us to map the structure of the global health research system, as it has evolved under the increased funding contributions of the past decade. Bearing in mind its structure, core functions and dynamic nature, we proposed a framework on how to effectively support the system to increase its efficiency. Results Based on our framework, which charted the structure and function of the global health research system and exposed places and roles for many stakeholders within the system, five basic needs emerged: (i) to co–ordinate funding among donors more effectively; (ii) to prioritize among many research ideas; (iii) to quickly recognize results of successful research; (iv) to ensure broad and rapid dissemination of results and their accessibility; and (v) to evaluate return on investments in health research. Conclusion The global health research system has evolved rapidly and spontaneously. It has not been optimally efficient, but it is possible to identify solutions that could improve this. There are already examples of effective responses for the need of prioritization of research questions (eg, the CHNRI method), quick recognition of important research (eg, systems used by editors of the leading journals) and rapid and broadly accessible publication of the new knowledge (eg, PLoS One journal as an example). It is still necessary to develop tools that could assist donors to co–ordinate funding and ensure more equity between areas in the provided support, and to evaluate the value for money invested in health research. PMID:26401270
Survey of local forestry-related ordinances and regulations in the south
Jonathan J. Spink; Karry L. Haney; John L. Greene
2000-01-01
A survey of the 13 southern states was conducted in 1999-2000 to obtain a comprehensive list of forestry-related ordinances enacted by various local governments. Each ordinance was examined to determine the date of adoption, regulatory objective, and its regu1atory provisions. Based on the regulatory objective, the ordinances were categorized into five general types:...
Knowledge of the ordinal position of list items in pigeons.
Scarf, Damian; Colombo, Michael
2011-10-01
Ordinal knowledge is a fundamental aspect of advanced cognition. It is self-evident that humans represent ordinal knowledge, and over the past 20 years it has become clear that nonhuman primates share this ability. In contrast, evidence that nonprimate species represent ordinal knowledge is missing from the comparative literature. To address this issue, in the present experiment we trained pigeons on three 4-item lists and then tested them with derived lists in which, relative to the training lists, the ordinal position of the items was either maintained or changed. Similar to the findings with human and nonhuman primates, our pigeons performed markedly better on the maintained lists compared to the changed lists, and displayed errors consistent with the view that they used their knowledge of ordinal position to guide responding on the derived lists. These findings demonstrate that the ability to acquire ordinal knowledge is not unique to the primate lineage. (PsycINFO Database Record (c) 2011 APA, all rights reserved).
Wilmoth, Siri K.; Irvine, Kathryn M.; Larson, Chad
2015-01-01
Various GIS-generated land-use predictor variables, physical habitat metrics, and water chemistry variables from 75 reference streams and 351 randomly sampled sites throughout Washington State were evaluated for effectiveness at discriminating reference from random sites within level III ecoregions. A combination of multivariate clustering and ordination techniques were used. We describe average observed conditions for a subset of predictor variables as well as proposing statistical criteria for establishing reference conditions for stream habitat in Washington. Using these criteria, we determined whether any of the random sites met expectations for reference condition and whether any of the established reference sites failed to meet expectations for reference condition. Establishing these criteria will set a benchmark from which future data will be compared.
Models of evaluation of public joint-stock property management
NASA Astrophysics Data System (ADS)
Yakupova, N. M.; Levachkova, S.; Absalyamova, S. G.; Kvon, G.
2017-12-01
The paper deals with the models of evaluation of performance of both the management company and the individual subsidiaries on the basis of a combination of elements and multi-parameter and target approaches. The article shows that due to the power of multi-dimensional and multi-directional indicators of financial and economic activity it is necessary to assess the degree of achievement of the objectives with the use of multivariate ordinal model as a set of indicators, ordered by growth so that the maintenance of this order on a long interval of time will ensure the effective functioning of the enterprise in the long term. It is shown that these models can be regarded as the monitoring tools of implementation of strategies and guide the justification effectiveness of implementation of management decisions.
Benthic algae of benchmark streams in agricultural areas of eastern Wisconsin
Scudder, Barbara C.; Stewart, Jana S.
2001-01-01
Multivariate analyses indicated multiple scales of environmental factors affect algae. Although two-way indicator species analysis (TWINSPAN), detrended correspondence analysis (DCA), and canonical correspondence analysis (CCA) generally separated sites according to RHU, only DCA ordination indicated a separation of sites according to ecoregion. Environmental variables con-elated with DCA axes 1 and 2 and therefore indicated as important explanatory factors for algal distribution and abundance were factors related to stream size, basin land use/cover, geomorphology, hydrogeology, and riparian disturbance. CCA analyses with a more limited set of environmental variables indicated that pH, average width of natural riparian vegetation (segment scale), basin land use/cover and Q/Q2 were the most important variables affecting the distribution and relative abundance of benthic algae at the 20 benchmark streams,
Cost-sensitive AdaBoost algorithm for ordinal regression based on extreme learning machine.
Riccardi, Annalisa; Fernández-Navarro, Francisco; Carloni, Sante
2014-10-01
In this paper, the well known stagewise additive modeling using a multiclass exponential (SAMME) boosting algorithm is extended to address problems where there exists a natural order in the targets using a cost-sensitive approach. The proposed ensemble model uses an extreme learning machine (ELM) model as a base classifier (with the Gaussian kernel and the additional regularization parameter). The closed form of the derived weighted least squares problem is provided, and it is employed to estimate analytically the parameters connecting the hidden layer to the output layer at each iteration of the boosting algorithm. Compared to the state-of-the-art boosting algorithms, in particular those using ELM as base classifier, the suggested technique does not require the generation of a new training dataset at each iteration. The adoption of the weighted least squares formulation of the problem has been presented as an unbiased and alternative approach to the already existing ELM boosting techniques. Moreover, the addition of a cost model for weighting the patterns, according to the order of the targets, enables the classifier to tackle ordinal regression problems further. The proposed method has been validated by an experimental study by comparing it with already existing ensemble methods and ELM techniques for ordinal regression, showing competitive results.
On analyzing ordinal data when responses and covariates are both missing at random.
Rana, Subrata; Roy, Surupa; Das, Kalyan
2016-08-01
In many occasions, particularly in biomedical studies, data are unavailable for some responses and covariates. This leads to biased inference in the analysis when a substantial proportion of responses or a covariate or both are missing. Except a few situations, methods for missing data have earlier been considered either for missing response or for missing covariates, but comparatively little attention has been directed to account for both missing responses and missing covariates, which is partly attributable to complexity in modeling and computation. This seems to be important as the precise impact of substantial missing data depends on the association between two missing data processes as well. The real difficulty arises when the responses are ordinal by nature. We develop a joint model to take into account simultaneously the association between the ordinal response variable and covariates and also that between the missing data indicators. Such a complex model has been analyzed here by using the Markov chain Monte Carlo approach and also by the Monte Carlo relative likelihood approach. Their performance on estimating the model parameters in finite samples have been looked into. We illustrate the application of these two methods using data from an orthodontic study. Analysis of such data provides some interesting information on human habit. © The Author(s) 2013.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tominaga, Nozomu; Shibata, Sanshiro; Blinnikov, Sergei I., E-mail: tominaga@konan-u.ac.jp, E-mail: sshibata@post.kek.jp, E-mail: Sergei.Blinnikov@itep.ru
We develop a time-dependent, multi-group, multi-dimensional relativistic radiative transfer code, which is required to numerically investigate radiation from relativistic fluids that are involved in, e.g., gamma-ray bursts and active galactic nuclei. The code is based on the spherical harmonic discrete ordinate method (SHDOM) which evaluates a source function including anisotropic scattering in spherical harmonics and implicitly solves the static radiative transfer equation with ray tracing in discrete ordinates. We implement treatments of time dependence, multi-frequency bins, Lorentz transformation, and elastic Thomson and inelastic Compton scattering to the publicly available SHDOM code. Our code adopts a mixed-frame approach; the source functionmore » is evaluated in the comoving frame, whereas the radiative transfer equation is solved in the laboratory frame. This implementation is validated using various test problems and comparisons with the results from a relativistic Monte Carlo code. These validations confirm that the code correctly calculates the intensity and its evolution in the computational domain. The code enables us to obtain an Eddington tensor that relates the first and third moments of intensity (energy density and radiation pressure) and is frequently used as a closure relation in radiation hydrodynamics calculations.« less
Terminal Duct Lobular Unit Involution of the Normal Breast: Implications for Breast Cancer Etiology
Pfeiffer, Ruth M.; Patel, Deesha A.; Linville, Laura; Brinton, Louise A.; Gierach, Gretchen L.; Yang, Xiaohong R.; Papathomas, Daphne; Visscher, Daniel; Mies, Carolyn; Degnim, Amy C.; Anderson, William F.; Hewitt, Stephen; Khodr, Zeina G.; Clare, Susan E.; Storniolo, Anna Maria; Sherman, Mark E.
2014-01-01
Background Greater degrees of terminal duct lobular unit (TDLU) involution have been linked to lower breast cancer risk; however, factors that influence this process are poorly characterized. Methods To study this question, we developed three reproducible measures that are inversely associated with TDLU involution: TDLU counts, median TDLU span, and median acini counts/TDLU. We determined factors associated with TDLU involution using normal breast tissues from 1938 participants (1369 premenopausal and 569 postmenopausal) ages 18 to 75 years in the Susan G. Komen Tissue Bank at the Indiana University Simon Cancer Center. Multivariable zero-inflated Poisson models were used to estimate relative risks (RRs) and 95% confidence intervals (95% CIs) for factors associated with TDLU counts, and multivariable ordinal logistic regression models were used to estimate odds ratios (ORs) and 95% CIs for factors associated with categories of median TDLU span and acini counts/TDLU. Results All TDLU measures started declining in the third age decade (all measures, two-sided P trend ≤ .001); and all metrics were statistically significantly lower among postmenopausal women. Nulliparous women demonstrated lower TDLU counts compared with uniparous women (among premenopausal women, RR = 0.79, 95% CI = 0.73 to 0.85; among postmenopausal, RR = 0.67, 95% CI = 0.56 to 0.79); however, rates of age-related TDLU decline were faster among parous women. Other factors were related to specific measures of TDLU involution. Conclusion Morphometric analysis of TDLU involution warrants further evaluation to understand the pathogenesis of breast cancer and assessing its role as a progression marker for women with benign biopsies or as an intermediate endpoint in prevention studies. PMID:25274491
Biological and Behavioral Risks for Incident Chlamydia trachomatis Infection in a Prospective Cohort
Hwang, Loris Y.; Ma, Yifei; Moscicki, Anna-Barbara
2014-01-01
Objective To identify biological and behavioral risks for incident Chlamydia trachomatis among a prospective cohort of young women followed frequently. Methods Our cohort of 629 women from two outpatient sites was seen every 4 months (October 2000 through April 2012) for behavioral interviews and infection testing. C trachomatis was tested annually, and anytime patients reported symptoms or possible exposure using commercial nucleic acid amplification tests. Analyses excluded baseline prevalent C trachomatis infections. Risk factors for incident C trachomatis were assessed using Cox proportional hazards models. Significant risks (p<0.10) from bivariate models were entered in a multivariate model, adjusted for four covariates chosen a priori (age, race or ethnicity, condom use, study site). Backwards step-wise elimination produced a final parsimonious model retaining significant variables (p<0.05) and the four adjustment variables. Results The 629 women attended 9,594 total visits. Median follow-up time was 6.9 years (interquartile range 3.2-9.8), during which 97 (15%) women had incident C trachomatis . In the final multivariate model, incident C trachomatis was independently associated with HPV at the preceding visit (p<0.01), smoking (p=0.02), and weekly use of substances besides alcohol and marijuana (p<0.01) since prior visit. Among 207 women with available colpophotographs (1,742 visits), cervical ectopy was not a significant risk factor (p range=0.16-0.39 for ectopy as continuous and ordinal variables). Conclusion Novel risks for C trachomatis include preceding HPV, smoking, and substance use, which may reflect both biological and behavioral mechanisms of risk, such as immune modulation, higher-risk sexual networks, or both. Improved understanding of the biological bases for C trachomatis risk would inform our strategies for C trachomatis control. PMID:25437724
Guan, Jian; Yi, Hongliang; Zou, Jianyin; Meng, Lili; Tang, Xulan; Zhu, Huaming; Yu, Dongzhen; Zhou, Huiqun; Su, Kaiming; Yang, Mingpo; Chen, Haoyan; Shi, Yongyong; Wang, Yue; Wang, Jian; Yin, Shankai
2016-01-01
Background Dyslipidaemia is an intermediary exacerbation factor for various diseases but the impact of obstructive sleep apnoea (OSA) on dyslipidaemia remains unclear. Methods A total of 3582 subjects with suspected OSA consecutively admitted to our hospital sleep centre were screened and 2983 (2422 with OSA) were included in the Shanghai Sleep Health Study. OSA severity was quantified using the apnoea–hypopnea index (AHI), the oxygen desaturation index and the arousal index. Biochemical indicators and anthropometric data were also collected. The relationship between OSA severity and the risk of dyslipidaemia was evaluated via ordinal logistic regression, restricted cubic spline (RCS) analysis and multivariate linear regressions. Results The RCS mapped a nonlinear dose–effect relationship between the risk of dyslipidaemia and OSA severity, and yielded knots of the AHI (9.4, 28.2, 54.4 and 80.2). After integrating the clinical definition and RCS-selected knots, all subjects were regrouped into four AHI severity stages. Following segmented multivariate linear modelling of each stage, distinguishable sets of OSA risk factors were quantified: low-density lipoprotein cholesterol (LDL-C), apolipoprotein E and high-density lipoprotein cholesterol (HDL-C); body mass index and/or waist to hip ratio; and HDL-C, LDL-C and triglycerides were specifically associated with stage I, stages II and III, and stages II–IV with different OSA indices. Conclusions Our study revealed the multistage and non-monotonic relationships between OSA and dyslipidaemia and quantified the relationships between OSA severity indexes and distinct risk factors for specific OSA severity stages. Our study suggests that a new interpretive and predictive strategy for dynamic assessment of the risk progression over the clinical course of OSA should be adopted. PMID:26883674
2013-01-01
Background To evaluate the effectiveness of a multifaceted intervention in improving emergency department (ED) patient privacy and satisfaction in the crowded ED setting. Methods A pre- and post-intervention study was conducted. A multifaceted intervention was implemented in a university-affiliated hospital ED. The intervention developed strategies to improve ED patient privacy and satisfaction, including redesigning the ED environment, process management, access control, and staff education and training, and encouraging ethics consultation. The effectiveness of the intervention was evaluated using patient surveys. Eligibility data were collected after the intervention and compared to data collected before the intervention. Differences in patient satisfaction and patient perception of privacy were adjusted for predefined covariates using multivariable ordinal logistic regression. Results Structured questionnaires were collected with 313 ED patients before the intervention and 341 ED patients after the intervention. There were no important covariate differences, except for treatment area, between the two groups. Significant improvements were observed in patient perception of “personal information overheard by others”, being “seen by irrelevant persons”, having “unintentionally heard inappropriate conversations from healthcare providers”, and experiencing “providers’ respect for my privacy”. There was significant improvement in patient overall perception of privacy and satisfaction. There were statistically significant correlations between the intervention and patient overall perception of privacy and satisfaction on multivariable analysis. Conclusions Significant improvements were achieved with an intervention. Patients perceived significantly more privacy and satisfaction in ED care after the intervention. We believe that these improvements were the result of major philosophical, administrative, and operational changes aimed at respecting both patient privacy and satisfaction. PMID:23421603
Expert Involvement Predicts mHealth App Downloads: Multivariate Regression Analysis of Urology Apps
Osório, Luís; Cavadas, Vitor; Fraga, Avelino; Carrasquinho, Eduardo; Cardoso de Oliveira, Eduardo; Castelo-Branco, Miguel; Roobol, Monique J
2016-01-01
Background Urological mobile medical (mHealth) apps are gaining popularity with both clinicians and patients. mHealth is a rapidly evolving and heterogeneous field, with some urology apps being downloaded over 10,000 times and others not at all. The factors that contribute to medical app downloads have yet to be identified, including the hypothetical influence of expert involvement in app development. Objective The objective of our study was to identify predictors of the number of urology app downloads. Methods We reviewed urology apps available in the Google Play Store and collected publicly available data. Multivariate ordinal logistic regression evaluated the effect of publicly available app variables on the number of apps being downloaded. Results Of 129 urology apps eligible for study, only 2 (1.6%) had >10,000 downloads, with half having ≤100 downloads and 4 (3.1%) having none at all. Apps developed with expert urologist involvement (P=.003), optional in-app purchases (P=.01), higher user rating (P<.001), and more user reviews (P<.001) were more likely to be installed. App cost was inversely related to the number of downloads (P<.001). Only data from the Google Play Store and the developers’ websites, but not other platforms, were publicly available for analysis, and the level and nature of expert involvement was not documented. Conclusions The explicit participation of urologists in app development is likely to enhance its chances to have a higher number of downloads. This finding should help in the design of better apps and further promote urologist involvement in mHealth. Official certification processes are required to ensure app quality and user safety. PMID:27421338
Identification of Users for a Smoking Cessation Mobile App: Quantitative Study.
Chevalking, S K Leon; Ben Allouch, Somaya; Brusse-Keizer, Marjolein; Postel, Marloes G; Pieterse, Marcel E
2018-04-09
The number of mobile apps that support smoking cessation is growing, indicating the potential of the mobile phone as a means to support cessation. Knowledge about the potential end users for cessation apps results in suggestions to target potential user groups in a dissemination strategy, leading to a possible increase in the satisfaction and adherence of cessation apps. This study aimed to characterize potential end users for a specific mobile health (mHealth) smoking cessation app. A quantitative study was conducted among 955 Dutch smokers and ex-smokers. The respondents were primarily recruited from addiction care facilities and hospitals through Web-based media via websites and forums. The respondents were surveyed on their demographics, smoking behavior, and personal innovativeness. The intention to use and the attitude toward a cessation app were determined on a 5-point Likert scale. To study the association between the characteristics and intention to use and attitude, univariate and multivariate ordinal logistic regression analyses were performed. The multivariate ordinal logistic regression showed that the number of previous quit attempts (odds ratio [OR] 4.1, 95% CI 2.4-7.0, and OR 3.5, 95% CI 2.0-5.9) and the score on the Fagerstrom Test of Nicotine Dependence (OR 0.8, 95% CI 0.8-0.9, and OR 0.8, 95% CI 0.8-0.9) positively correlates with the intention to use a cessation app and the attitude toward cessation apps, respectively. Personal innovativeness also positively correlates with the intention to use (OR 0.3, 95% CI 0.2-0.4) and the attitude towards (OR 0.2, 95% CI 0.1-0.4) a cessation app. No associations between demographics and the intention to use or the attitude toward using a cessation app were observed. This study is among the first to show that demographic characteristics such as age and level of education are not associated with the intention to use and the attitude toward using a cessation app when characteristics related specifically to the app, such as nicotine dependency and the number of quit attempts, are present in a multivariate regression model. This study shows that the use of mHealth apps depends on characteristics related to the content of the app rather than general user characteristics. ©S K Leon Chevalking, Somaya Ben Allouch, Marjolein Brusse-Keizer, Marloes G Postel, Marcel E Pieterse. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 09.04.2018.
Community-level policy responses to state marijuana legalization in Washington State
Dilley, Julia A.; Hitchcock, Laura; McGroder, Nancy; Greto, Lindsey A.; Richardson, Susan M.
2017-01-01
Background Washington State (WA) legalized a recreational marijuana market -- including growing, processing and retail sales -- through voter initiative 502 in November 2012. Legalized recreational marijuana retail sales began in July 2014. In response to state legalization of recreational marijuana, some cities and counties within the state have passed local ordinances that either further regulated marijuana markets, or banned them completely. The purpose of this study is to describe local-level marijuana regulations on recreational retail sales within the context of a state that had legalized a recreational marijuana market. Methods Marijuana-related ordinances were collected from all 142 cities in the state with more than 3,000 residents and from all 39 counties. Policies that were in place as of June 30, 2016 - two years after the state’s recreational market opening - to regulate recreational marijuana retail sales within communities were systematically coded. Results A total of 125 cities and 30 counties had passed local ordinances to address recreational marijuana retail sales. Multiple communities implemented retail market bans, including some temporary bans (moratoria) while studying whether to pursue other policy options. As of June 30, 2016, 30% of the state population lived in places that had temporarily or permanently banned retail sales. Communities most frequently enacted zoning policies explicitly regulating where marijuana businesses could be established. Other policies included in ordinances placed limits on business hours and distance requirements (buffers) between marijuana businesses and youth-related land use types or other sensitive areas. Conclusions State legalization does not necessarily result in uniform community environments that regulate recreational marijuana markets. Local ordinances vary among communities within Washington following statewide legalization. Further study is needed to describe how such local policies affect variation in public health and social outcomes. PMID:28365192
Urban Runoff: Model Ordinances for Erosion and Sediment Control
The model ordinance in this section borrows language from the erosion and sediment control ordinance features that might help prevent erosion and sedimentation and protect natural resources more fully.
Zhang, Guilian; Zhang, Jintun; Guo, Xiaoyu
2005-01-01
By the methods of TWINSPAN, DCA and DCCA, and from the aspects of the relations between plant species, communities and environmental factors, this paper studied the ecological relationships among artificial vegetations during their restoration in Antaibao mining area. 63 collected quadrates were classified into 12 community types by TWINSPAN, and the distribution of the communities could comprehensively reflect the influence of environmental factors. DCA ordination indicated that soil water content, which was increased with restoration time, was the main factor restricting the distribution of the communities. DCCA ordination showed that soil organic matter content was the decisive factor to the development of communities.
Quantitative Evaluation of Management Courses: Part 1
ERIC Educational Resources Information Center
Cunningham, Cyril
1973-01-01
The author describes how he developed a method of evaluating and comparing management courses of different types and lengths by applying an ordinal system of relative values using a process of transmutation. (MS)
Dolan, Paul; Tsuchiya, Aki
2003-06-01
The person trade-off (PTO) is increasingly being used to elicit preferences in health. This paper explores the measurement properties of the PTO method in the context of a study about how members of the public prioritise between patients of different ages. In particular, it considers whether PTO responses satisfy the transitivity principle; that is, whether one PTO response can be inferred from two other PTO responses. The results suggest that very few responses to PTO questions satisfy cardinal transitivity condition. However, this study has produced results that suggest that cardinal transitivity will hold, on average, when respondents who fail to satisfy the ordinal transitivity condition have been excluded from the analysis. This suggests that future PTO studies should build in checks for ordinal transitivity. Copyright 2002 John Wiley & Sons, Ltd.
Predictors of Upper-Extremity Physical Function in Older Adults.
Hermanussen, Hugo H; Menendez, Mariano E; Chen, Neal C; Ring, David; Vranceanu, Ana-Maria
2016-10-01
Little is known about the influence of habitual participation in physical exercise and diet on upper-extremity physical function in older adults. To assess the relationship of general physical exercise and diet to upper-extremity physical function and pain intensity in older adults. A cohort of 111 patients 50 or older completed a sociodemographic survey, the Rapid Assessment of Physical Activity (RAPA), an 11-point ordinal pain intensity scale, a Mediterranean diet questionnaire, and three Patient- Reported Outcomes Measurement Information System (PROMIS) based questionnaires: Pain Interference to measure inability to engage in activities due to pain, Upper-Extremity Physical Function, and Depression. Multivariable linear regression modeling was used to characterize the association of physical activity, diet, depression, and pain interference to pain intensity and upper-extremity function. Higher general physical activity was associated with higher PROMIS Upper-Extremity Physical Function and lower pain intensity in bivariate analyses. Adherence to the Mediterranean diet did not correlate with PROMIS Upper-Extremity Physical Function or pain intensity in bivariate analysis. In multivariable analyses factors associated with higher PROMIS Upper-Extremity Physical Function were male sex, non-traumatic diagnosis and PROMIS Pain Interference, with the latter accounting for most of the observed variability (37%). Factors associated with greater pain intensity in multivariable analyses included fewer years of education and higher PROMIS Pain Interference. General physical activity and diet do not seem to be as strongly or directly associated with upper-extremity physical function as pain interference.
Methods for the analysis of ordinal response data in medical image quality assessment.
Keeble, Claire; Baxter, Paul D; Gislason-Lee, Amber J; Treadgold, Laura A; Davies, Andrew G
2016-07-01
The assessment of image quality in medical imaging often requires observers to rate images for some metric or detectability task. These subjective results are used in optimization, radiation dose reduction or system comparison studies and may be compared to objective measures from a computer vision algorithm performing the same task. One popular scoring approach is to use a Likert scale, then assign consecutive numbers to the categories. The mean of these response values is then taken and used for comparison with the objective or second subjective response. Agreement is often assessed using correlation coefficients. We highlight a number of weaknesses in this common approach, including inappropriate analyses of ordinal data and the inability to properly account for correlations caused by repeated images or observers. We suggest alternative data collection and analysis techniques such as amendments to the scale and multilevel proportional odds models. We detail the suitability of each approach depending upon the data structure and demonstrate each method using a medical imaging example. Whilst others have raised some of these issues, we evaluated the entire study from data collection to analysis, suggested sources for software and further reading, and provided a checklist plus flowchart for use with any ordinal data. We hope that raised awareness of the limitations of the current approaches will encourage greater method consideration and the utilization of a more appropriate analysis. More accurate comparisons between measures in medical imaging will lead to a more robust contribution to the imaging literature and ultimately improved patient care.
NASA Astrophysics Data System (ADS)
KIM, Jong Woon; LEE, Young-Ouk
2017-09-01
As computing power gets better and better, computer codes that use a deterministic method seem to be less useful than those using the Monte Carlo method. In addition, users do not like to think about space, angles, and energy discretization for deterministic codes. However, a deterministic method is still powerful in that we can obtain a solution of the flux throughout the problem, particularly as when particles can barely penetrate, such as in a deep penetration problem with small detection volumes. Recently, a new state-of-the-art discrete-ordinates code, ATTILA, was developed and has been widely used in several applications. ATTILA provides the capabilities to solve geometrically complex 3-D transport problems by using an unstructured tetrahedral mesh. Since 2009, we have been developing our own code by benchmarking ATTILA. AETIUS is a discrete ordinates code that uses an unstructured tetrahedral mesh such as ATTILA. For pre- and post- processing, Gmsh is used to generate an unstructured tetrahedral mesh by importing a CAD file (*.step) and visualizing the calculation results of AETIUS. Using a CAD tool, the geometry can be modeled very easily. In this paper, we describe a brief overview of AETIUS and provide numerical results from both AETIUS and a Monte Carlo code, MCNP5, in a deep penetration problem with small detection volumes. The results demonstrate the effectiveness and efficiency of AETIUS for such calculations.
On the ordinality of numbers: A review of neural and behavioral studies.
Lyons, I M; Vogel, S E; Ansari, D
2016-01-01
The last several years have seen steady growth in research on the cognitive and neuronal mechanisms underlying how numbers are represented as part of ordered sequences. In the present review, we synthesize what is currently known about numerical ordinality from behavioral and neuroimaging research, point out major gaps in our current knowledge, and propose several hypotheses that may bear further investigation. Evidence suggests that how we process ordinality differs from how we process cardinality, but that this difference depends strongly on context-in particular, whether numbers are presented symbolically or nonsymbolically. Results also reveal many commonalities between numerical and nonnumerical ordinal processing; however, the degree to which numerical ordinality can be reduced to domain-general mechanisms remains unclear. One proposal is that numerical ordinality relies upon more general short-term memory mechanisms as well as more numerically specific long-term memory representations. It is also evident that numerical ordinality is highly multifaceted, with symbolic representations in particular allowing for a wide range of different types of ordinal relations, the complexity of which appears to increase over development. We examine the proposal that these relations may form the basis of a richer set of associations that may prove crucial to the emergence of more complex math abilities and concepts. In sum, ordinality appears to be an important and relatively understudied facet of numerical cognition that presents substantial opportunities for new and ground-breaking research. © 2016 Elsevier B.V. All rights reserved.
Cohen, D; Stamnes, S; Tanikawa, T; Sommersten, E R; Stamnes, J J; Lotsberg, J K; Stamnes, K
2013-04-22
A comparison is presented of two different methods for polarized radiative transfer in coupled media consisting of two adjacent slabs with different refractive indices, each slab being a stratified medium with no change in optical properties except in the direction of stratification. One of the methods is based on solving the integro-differential radiative transfer equation for the two coupled slabs using the discrete ordinate approximation. The other method is based on probabilistic and statistical concepts and simulates the propagation of polarized light using the Monte Carlo approach. The emphasis is on non-Rayleigh scattering for particles in the Mie regime. Comparisons with benchmark results available for a slab with constant refractive index show that both methods reproduce these benchmark results when the refractive index is set to be the same in the two slabs. Computed results for test cases with coupling (different refractive indices in the two slabs) show that the two methods produce essentially identical results for identical input in terms of absorption and scattering coefficients and scattering phase matrices.
Compliance to two city convenience store ordinance requirements
Menéndez, Cammie K Chaumont; Amandus, Harlan E; Wu, Nan; Hendricks, Scott A
2015-01-01
Background Robbery-related homicides and assaults are the leading cause of death in retail businesses. Robbery reduction approaches focus on compliance to Crime Prevention Through Environmental Design (CPTED) guidelines. Purpose We evaluated the level of compliance to CPTED guidelines specified by convenience store safety ordinances effective in 2010 in Dallas and Houston, Texas, USA. Methods Convenience stores were defined as businesses less than 10 000 square feet that sell grocery items. Store managers were interviewed for store ordinance requirements from August to November 2011, in a random sample of 594 (289 in Dallas, 305 in Houston) convenience stores that were open before and after the effective dates of their city’s ordinance. Data were collected in 2011 and analysed in 2012–2014. Results Overall, 9% of stores were in full compliance, although 79% reported being registered with the police departments as compliant. Compliance was consistently significantly higher in Dallas than in Houston for many requirements and by store type. Compliance was lower among single owner-operator stores compared with corporate/franchise stores. Compliance to individual requirements was lowest for signage and visibility. Conclusions Full compliance to the required safety measures is consistent with industry ‘best practices’ and evidence-based workplace violence prevention research findings. In Houston and Dallas compliance was higher for some CPTED requirements but not the less costly approaches that are also the more straightforward to adopt. PMID:26337569
NASA Astrophysics Data System (ADS)
Molina Garcia, Victor; Sasi, Sruthy; Efremenko, Dmitry; Doicu, Adrian; Loyola, Diego
2017-04-01
In this work, the requirements for the retrieval of cloud properties in the back-scattering region are described, and their application to the measurements taken by the Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR) is shown. Various radiative transfer models and their linearizations are implemented, and their advantages and issues are analyzed. As radiative transfer calculations in the back-scattering region are computationally time-consuming, several acceleration techniques are also studied. The radiative transfer models analyzed include the exact Discrete Ordinate method with Matrix Exponential (DOME), the Matrix Operator method with Matrix Exponential (MOME), and the approximate asymptotic and equivalent Lambertian cloud models. To reduce the computational cost of the line-by-line (LBL) calculations, the k-distribution method, the Principal Component Analysis (PCA) and a combination of the k-distribution method plus PCA are used. The linearized radiative transfer models for retrieval of cloud properties include the Linearized Discrete Ordinate method with Matrix Exponential (LDOME), the Linearized Matrix Operator method with Matrix Exponential (LMOME) and the Forward-Adjoint Discrete Ordinate method with Matrix Exponential (FADOME). These models were applied to the EPIC oxygen-A band absorption channel at 764 nm. It is shown that the approximate asymptotic and equivalent Lambertian cloud models give inaccurate results, so an offline processor for the retrieval of cloud properties in the back-scattering region requires the use of exact models such as DOME and MOME, which behave similarly. The combination of the k-distribution method plus PCA presents similar accuracy to the LBL calculations, but it is up to 360 times faster, and the relative errors for the computed radiances are less than 1.5% compared to the results when the exact phase function is used. Finally, the linearized models studied show similar behavior, with relative errors less than 1% for the radiance derivatives, but FADOME is 2 times faster than LDOME and 2.5 times faster than LMOME.
Generalized Mantel-Haenszel Methods for Differential Item Functioning Detection
ERIC Educational Resources Information Center
Fidalgo, Angel M.; Madeira, Jaqueline M.
2008-01-01
Mantel-Haenszel methods comprise a highly flexible methodology for assessing the degree of association between two categorical variables, whether they are nominal or ordinal, while controlling for other variables. The versatility of Mantel-Haenszel analytical approaches has made them very popular in the assessment of the differential functioning…
Tests of Independence for Ordinal Data Using Bootstrap.
ERIC Educational Resources Information Center
Chan, Wai; Yung, Yiu-Fai; Bentler, Peter M.; Tang, Man-Lai
1998-01-01
Two bootstrap tests are proposed to test the independence hypothesis in a two-way cross table. Monte Carlo studies are used to compare the traditional asymptotic test with these bootstrap methods, and the bootstrap methods are found superior in two ways: control of Type I error and statistical power. (SLD)
Implementation of radiation shielding calculation methods. Volume 2: Seminar/Workshop notes
NASA Technical Reports Server (NTRS)
Capo, M. A.; Disney, R. K.
1971-01-01
Detailed descriptions are presented of the input data for each of the MSFC computer codes applied to the analysis of a realistic nuclear propelled vehicle. The analytical techniques employed include cross section data, preparation, one and two dimensional discrete ordinates transport, point kernel, and single scatter methods.
Improving Your Exploratory Factor Analysis for Ordinal Data: A Demonstration Using FACTOR
ERIC Educational Resources Information Center
Baglin, James
2014-01-01
Exploratory factor analysis (EFA) methods are used extensively in the field of assessment and evaluation. Due to EFA's widespread use, common methods and practices have come under close scrutiny. A substantial body of literature has been compiled highlighting problems with many of the methods and practices used in EFA, and, in response, many…
NASA Astrophysics Data System (ADS)
Jin, Y.; Liang, Z.
2002-12-01
The vector radiative transfer (VRT) equation is an integral-deferential equation to describe multiple scattering, absorption and transmission of four Stokes parameters in random scatter media. From the integral formal solution of VRT equation, the lower order solutions, such as the first-order scattering for a layer medium or the second order scattering for a half space, can be obtained. The lower order solutions are usually good at low frequency when high-order scattering is negligible. It won't be feasible to continue iteration for obtaining high order scattering solution because too many folds integration would be involved. In the space-borne microwave remote sensing, for example, the DMSP (Defense Meterological Satellite Program) SSM/I (Special Sensor Microwave/Imager) employed seven channels of 19, 22, 37 and 85GHz. Multiple scattering from the terrain surfaces such as snowpack cannot be neglected at these channels. The discrete ordinate and eigen-analysis method has been studied to take into account for multiple scattering and applied to remote sensing of atmospheric precipitation, snowpack etc. Snowpack was modeled as a layer of dense spherical particles, and the VRT for a layer of uniformly dense spherical particles has been numerically studied by the discrete ordinate method. However, due to surface melting and refrozen crusts, the snowpack undergoes stratifying to form inhomegeneous profiles of the ice grain size, fractional volume and physical temperature etc. It becomes necessary to study multiple scattering and emission from stratified snowpack of dense ice grains. But, the discrete ordinate and eigen-analysis method cannot be simply applied to multi-layers model, because numerically solving a set of multi-equations of VRT is difficult. Stratifying the inhomogeneous media into multi-slabs and employing the first order Mueller matrix of each thin slab, this paper developed an iterative method to derive high orders scattering solutions of whole scatter media. High order scattering and emission from inhomogeneous stratifying media of dense spherical particles are numerically obtained. The brightness temperature at low frequency such as 5.3 GHz without high order scattering and at SSM/I channels with high order scattering are obtained. This approach is also compared with the conventional discrete ordinate method for an uniform layer model. Numerical simulation for inhomogeneous snowpack is also compared with the measurements of microwave remote sensing.
Reduction from cost-sensitive ordinal ranking to weighted binary classification.
Lin, Hsuan-Tien; Li, Ling
2012-05-01
We present a reduction framework from ordinal ranking to binary classification. The framework consists of three steps: extracting extended examples from the original examples, learning a binary classifier on the extended examples with any binary classification algorithm, and constructing a ranker from the binary classifier. Based on the framework, we show that a weighted 0/1 loss of the binary classifier upper-bounds the mislabeling cost of the ranker, both error-wise and regret-wise. Our framework allows not only the design of good ordinal ranking algorithms based on well-tuned binary classification approaches, but also the derivation of new generalization bounds for ordinal ranking from known bounds for binary classification. In addition, our framework unifies many existing ordinal ranking algorithms, such as perceptron ranking and support vector ordinal regression. When compared empirically on benchmark data sets, some of our newly designed algorithms enjoy advantages in terms of both training speed and generalization performance over existing algorithms. In addition, the newly designed algorithms lead to better cost-sensitive ordinal ranking performance, as well as improved listwise ranking performance.
Xia, Ming-Feng; Bian, Hua; Zhu, Xiao-Peng; Yan, Hong-Mei; Chang, Xin-Xia; Zhang, Lin-Shan; Lin, Huan-Dong; Hu, Xi-Qi; Gao, Xin
2017-06-28
Non-alcoholic fatty liver disease (NAFLD) is a common and strong risk factor for cardiovascular disease and hepatocellular carcinoma. The rapid acceleration of the increase in NAFLD prevalence has exceeded the trends observed for obesity, and has been driven by multiple factors. The aim of this study was to investigate the correlation between the serum levels of folic acid, the endogenous source of methyl groups for DNA methylation, and NAFLD in Chinese adults. The correlations between the serum folic acid levels and NAFLD were investigated in two independent cohorts of 70 subjects who underwent a liver biopsy and 130 subjects with varying liver fat contents, as measured using proton magnetic resonance spectroscopy ( 1 H-MRS). Independent correlations between serum folic acid levels and liver steatosis grades were detected using a multivariate ordinal regression analysis. The diagnostic performances of serum folic acid levels alone and in combination with existing NAFLD prediction scores were compared with those of traditional NAFLD prediction parameters using receiver operating characteristic (ROC) curve analyses. Serum folic acid concentrations were inversely correlated with liver histological steatosis grades (ρ = -0.371, P < 0.001) and the 1 H-MRS-measured liver fat content (r = -0.199, P = 0.038). According to the multivariate ordinal regression analysis, serum folic acid levels were inversely correlated with liver steatosis grades (OR 0.739 [0.594-0.918], P = 0.006) independent of age, gender, BMI, components of metabolic syndrome and the serum TC, LDL-c and HOMA-IR levels. The AUROC of serum folic acid for the diagnosis of NAFLD was 0.75 (0.65-0.83), and the addition of serum folic acid to NAFLD prediction scores significantly improved the diagnostic prediction of NAFLD (AUROC = 0.88 [0.81-0.94]). Low serum folic acid levels were identified as an independent risk factor for NAFLD in the Chinese population. The addition of the serum folic acid levels to the current existing NAFLD prediction scores significantly improved the prediction of NAFLD. Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Impact of San Francisco's toy ordinance on restaurants and children's food purchases, 2011-2012.
Otten, Jennifer J; Saelens, Brian E; Kapphahn, Kristopher I; Hekler, Eric B; Buman, Matthew P; Goldstein, Benjamin A; Krukowski, Rebecca A; O'Donohue, Laura S; Gardner, Christopher D; King, Abby C
2014-07-17
In 2011, San Francisco passed the first citywide ordinance to improve the nutritional standards of children's meals sold at restaurants by preventing the giving away of free toys or other incentives with meals unless nutritional criteria were met. This study examined the impact of the Healthy Food Incentives Ordinance at ordinance-affected restaurants on restaurant response (eg, toy-distribution practices, change in children's menus), and the energy and nutrient content of all orders and children's-meal-only orders purchased for children aged 0 through 12 years. Restaurant responses were examined from January 2010 through March 2012. Parent-caregiver/child dyads (n = 762) who were restaurant customers were surveyed at 2 points before and 1 seasonally matched point after ordinance enactment at Chain A and B restaurants (n = 30) in 2011 and 2012. Both restaurant chains responded to the ordinance by selling toys separately from children's meals, but neither changed their menus to meet ordinance-specified nutrition criteria. Among children for whom children's meals were purchased, significant decreases in kilocalories, sodium, and fat per order were likely due to changes in children's side dishes and beverages at Chain A. Although the changes at Chain A did not appear to be directly in response to the ordinance, the transition to a more healthful beverage and default side dish was consistent with the intent of the ordinance. Study results underscore the importance of policy wording, support the concept that more healthful defaults may be a powerful approach for improving dietary intake, and suggest that public policies may contribute to positive restaurant changes.
Radiative heat transfer in strongly forward scattering media using the discrete ordinates method
NASA Astrophysics Data System (ADS)
Granate, Pedro; Coelho, Pedro J.; Roger, Maxime
2016-03-01
The discrete ordinates method (DOM) is widely used to solve the radiative transfer equation, often yielding satisfactory results. However, in the presence of strongly forward scattering media, this method does not generally conserve the scattering energy and the phase function asymmetry factor. Because of this, the normalization of the phase function has been proposed to guarantee that the scattering energy and the asymmetry factor are conserved. Various authors have used different normalization techniques. Three of these are compared in the present work, along with two other methods, one based on the finite volume method (FVM) and another one based on the spherical harmonics discrete ordinates method (SHDOM). In addition, the approximation of the Henyey-Greenstein phase function by a different one is investigated as an alternative to the phase function normalization. The approximate phase function is given by the sum of a Dirac delta function, which accounts for the forward scattering peak, and a smoother scaled phase function. In this study, these techniques are applied to three scalar radiative transfer test cases, namely a three-dimensional cubic domain with a purely scattering medium, an axisymmetric cylindrical enclosure containing an emitting-absorbing-scattering medium, and a three-dimensional transient problem with collimated irradiation. The present results show that accurate predictions are achieved for strongly forward scattering media when the phase function is normalized in such a way that both the scattered energy and the phase function asymmetry factor are conserved. The normalization of the phase function may be avoided using the FVM or the SHDOM to evaluate the in-scattering term of the radiative transfer equation. Both methods yield results whose accuracy is similar to that obtained using the DOM along with normalization of the phase function. Very satisfactory predictions were also achieved using the delta-M phase function, while the delta-Eddington phase function and the transport approximation may perform poorly.
Evaluation of diagnostic accuracy in detecting ordered symptom statuses without a gold standard
Wang, Zheyu; Zhou, Xiao-Hua; Wang, Miqu
2011-01-01
Our research is motivated by 2 methodological problems in assessing diagnostic accuracy of traditional Chinese medicine (TCM) doctors in detecting a particular symptom whose true status has an ordinal scale and is unknown—imperfect gold standard bias and ordinal scale symptom status. In this paper, we proposed a nonparametric maximum likelihood method for estimating and comparing the accuracy of different doctors in detecting a particular symptom without a gold standard when the true symptom status had an ordered multiple class. In addition, we extended the concept of the area under the receiver operating characteristic curve to a hyper-dimensional overall accuracy for diagnostic accuracy and alternative graphs for displaying a visual result. The simulation studies showed that the proposed method had good performance in terms of bias and mean squared error. Finally, we applied our method to our motivating example on assessing the diagnostic abilities of 5 TCM doctors in detecting symptoms related to Chills disease. PMID:21209155
A Method for Optimal Load Dispatch of a Multi-zone Power System with Zonal Exchange Constraints
NASA Astrophysics Data System (ADS)
Hazarika, Durlav; Das, Ranjay
2018-04-01
This paper presented a method for economic generation scheduling of a multi-zone power system having inter zonal operational constraints. For this purpose, the generator rescheduling for a multi area power system having inter zonal operational constraints has been represented as a two step optimal generation scheduling problem. At first, the optimal generation scheduling has been carried out for the zone having surplus or deficient generation with proper spinning reserve using co-ordination equation. The power exchange required for the deficit zones and zones having no generation are estimated based on load demand and generation for the zone. The incremental transmission loss formulas for the transmission lines participating in the power transfer process among the zones are formulated. Using these, incremental transmission loss expression in co-ordination equation, the optimal generation scheduling for the zonal exchange has been determined. Simulation is carried out on IEEE 118 bus test system to examine the applicability and validity of the method.
Earth-System Scales of Biodiversity Variability in Shallow Continental Margin Seafloor Ecosystems
NASA Astrophysics Data System (ADS)
Moffitt, S. E.; White, S. M.; Hill, T. M.; Kennett, J.
2015-12-01
High-resolution paleoceanographic sedimentary sequences allow for the description of ecosystem sensitivity to earth-system scales of climate and oceanographic change. Such archives from Santa Barbara Basin, California record the ecological consequences to seafloor ecosystems of climate-forced shifts in the California Current Oxygen Minimum Zone (OMZ). Here we use core MV0508-20JPC dated to 735,000±5,000 years ago (Marine Isotope Stage 18) as a "floating window" of millennial-scale ecological variability. For this investigation, previously published archives of planktonic δ18O (Globigerina bulloides) record stadial and interstadial oscillations in surface ocean temperature. Core MV0508-20JPC is an intermittently laminated archive, strongly influenced by the California Current OMZ, with continuously preserved benthic foraminifera and discontinuously preserved micro-invertebrates, including ophiuroids, echinoderms, ostracods, gastropods, bivalves and scaphopods. Multivariate statistical approaches, such as ordinations and cluster analyses, describe climate-driven changes in both foraminiferal and micro-invertebrate assemblages. Statistical ordinations illustrate that the shallow continental margin seafloor underwent predictable phase-shifts in oxygenation and biodiversity across stadial and interstadial events. A narrow suite of severely hypoxic taxa characterized foraminiferal communities from laminated intervals, including Bolivina tumida, Globobulimina spp., and Nonionella stella. Foraminiferal communities from bioturbated intervals are diverse and >60% similar to each other, and they are associated with echinoderm, ostracod and mollusc fossils. As with climate shifts in the latest Quaternary, there is a sensitive benthic ecosystem response in mid-Pleistocene continental margins to climatically related changes in OMZ strength.
2017-03-23
solutions obtained through their proposed method to comparative instances of a generalized assignment problem with either ordinal cost components or... method flag: Designates the method by which the changed/ new assignment problem instance is solved. methodFlag = 0:SMAWarmstart Returns a matching...of randomized perturbations. We examine the contrasts between these methods in the context of assigning Army Officers among a set of identified
NASA Astrophysics Data System (ADS)
Bhattacharjya, Rajib Kumar
2018-05-01
The unit hydrograph and the infiltration parameters of a watershed can be obtained from observed rainfall-runoff data by using inverse optimization technique. This is a two-stage optimization problem. In the first stage, the infiltration parameters are obtained and the unit hydrograph ordinates are estimated in the second stage. In order to combine this two-stage method into a single stage one, a modified penalty parameter approach is proposed for converting the constrained optimization problem to an unconstrained one. The proposed approach is designed in such a way that the model initially obtains the infiltration parameters and then searches the optimal unit hydrograph ordinates. The optimization model is solved using Genetic Algorithms. A reduction factor is used in the penalty parameter approach so that the obtained optimal infiltration parameters are not destroyed during subsequent generation of genetic algorithms, required for searching optimal unit hydrograph ordinates. The performance of the proposed methodology is evaluated by using two example problems. The evaluation shows that the model is superior, simple in concept and also has the potential for field application.
NASA Astrophysics Data System (ADS)
Rozanov, Vladimir V.; Vountas, Marco
2014-01-01
Rotational Raman scattering of solar light in Earth's atmosphere leads to the filling-in of Fraunhofer and telluric lines observed in the reflected spectrum. The phenomenological derivation of the inelastic radiative transfer equation including rotational Raman scattering is presented. The different forms of the approximate radiative transfer equation with first-order rotational Raman scattering terms are obtained employing the Cabannes, Rayleigh, and Cabannes-Rayleigh scattering models. The solution of these equations is considered in the framework of the discrete-ordinates method using rigorous and approximate approaches to derive particular integrals. An alternative forward-adjoint technique is suggested as well. A detailed description of the model including the exact spectral matching and a binning scheme that significantly speeds up the calculations is given. The considered solution techniques are implemented in the radiative transfer software package SCIATRAN and a specified benchmark setup is presented to enable readers to compare with own results transparently.
A measure of association for ordered categorical data in population-based studies
Nelson, Kerrie P; Edwards, Don
2016-01-01
Ordinal classification scales are commonly used to define a patient’s disease status in screening and diagnostic tests such as mammography. Challenges arise in agreement studies when evaluating the association between many raters’ classifications of patients’ disease or health status when an ordered categorical scale is used. In this paper, we describe a population-based approach and chance-corrected measure of association to evaluate the strength of relationship between multiple raters’ ordinal classifications where any number of raters can be accommodated. In contrast to Shrout and Fleiss’ intraclass correlation coefficient, the proposed measure of association is invariant with respect to changes in disease prevalence. We demonstrate how unique characteristics of individual raters can be explored using random effects. Simulation studies are conducted to demonstrate the properties of the proposed method under varying assumptions. The methods are applied to two large-scale agreement studies of breast cancer screening and prostate cancer severity. PMID:27184590
a Numerical Method for Stability Analysis of Pinned Flexible Mechanisms
NASA Astrophysics Data System (ADS)
Beale, D. G.; Lee, S. W.
1996-05-01
A technique is presented to investigate the stability of mechanisms with pin-jointed flexible members. The method relies on a special floating frame from which elastic link co-ordinates are defined. Energies are easily developed for use in a Lagrange equation formulation, leading to a set of non-linear and mixed ordinary differential-algebraic equations of motion with constraints. Stability and bifurcation analysis is handled using a numerical procedure (generalized co-ordinate partitioning) that avoids the tedious and difficult task of analytically reducing the system of equations to a number equalling the system degrees of freedom. The proposed method was then applied to (1) a slider-crank mechanism with a flexible connecting rod and crank of constant rotational speed, and (2) a four-bar linkage with a flexible coupler with a constant speed crank. In both cases, a single pinned-pinned beam bending mode is employed to develop resonance curves and stability boundaries in the crank length-crank speed parameter plane. Flip and fold bifurcations are common occurrences in both mechanisms. The accuracy of the proposed method was also verified by comparison with previous experimental results [1].
NASA Astrophysics Data System (ADS)
Widyaningsih, Purnami; Retno Sari Saputro, Dewi; Nugrahani Putri, Aulia
2017-06-01
GWOLR model combines geographically weighted regression (GWR) and (ordinal logistic reression) OLR models. Its parameter estimation employs maximum likelihood estimation. Such parameter estimation, however, yields difficult-to-solve system of nonlinear equations, and therefore numerical approximation approach is required. The iterative approximation approach, in general, uses Newton-Raphson (NR) method. The NR method has a disadvantage—its Hessian matrix is always the second derivatives of each iteration so it does not always produce converging results. With regard to this matter, NR model is modified by substituting its Hessian matrix into Fisher information matrix, which is termed Fisher scoring (FS). The present research seeks to determine GWOLR model parameter estimation using Fisher scoring method and apply the estimation on data of the level of vulnerability to Dengue Hemorrhagic Fever (DHF) in Semarang. The research concludes that health facilities give the greatest contribution to the probability of the number of DHF sufferers in both villages. Based on the number of the sufferers, IR category of DHF in both villages can be determined.
Song, Tingting; Wittkowski, Knut M.
2010-01-01
Ordinal measures are frequently encountered in travel behavior research. This paper presents a new method for combining them when a hierarchical structure of the data can be presumed. This method is applied to study the subjective assessment of the amount of travel by different transportation modes among a group of French clerical workers, along with the desire to increase or decrease the use of such modes. Some advantages of this approach over traditional data reduction technique such as factor analysis when applied to ordinal data are then illustrated. In this study, combining evidence from several variables sheds light on the observed moderately negative relationship between the personal assessment of the amount of travel and the desire to increase or decrease it, thus integrating previous partial (univariate) results. We find a latent demand for travel, thus contributing to clarify the behavioral mechanisms behind the induced traffic phenomenon. Categorizing the above relationship by transportation mode shows a desire for a less environmental-friendly mix of modes (i.e. a greater desire to use heavy motorized modes and a lower desire to use two-wheeled modes), whenever the respondents do not feel to travel extensively. This result, combined with previous theoretical investigations concerning the determinants of the desire to alter trips consumption levels, shows the importance of making people aware of how much they travel. PMID:20953273
75 FR 75694 - Klamath Tribes Liquor Control Ordinance Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-06
... DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs Klamath Tribes Liquor Control Ordinance... Control Ordinance of the Klamath Tribes. This correction removes incorrect references to an amended... follows: SUMMARY: This notice publishes the Secretary's certification of the Klamath Tribes Liquor Control...
NASA Technical Reports Server (NTRS)
Ladson, C. L.; Brooks, Cuyler W., Jr.
1975-01-01
A computer program developed to calculate the ordinates and surface slopes of any thickness, symmetrical or cambered NACA airfoil of the 4-digit, 4-digit modified, 5-digit, and 16-series airfoil families is presented. The program produces plots of the airfoil nondimensional ordinates and a punch card output of ordinates in the input format of a readily available program for determining the pressure distributions of arbitrary airfoils in subsonic potential viscous flow.
THE RELATIONSHIP BETWEEN INJURY SEVERITY AND INDIVIDUAL CHARACTERISTICS: A SURVEY IN SOUTHERN CHINA.
Huang, Kaiyong; Liang, Wenjie; Han, Shanshan; Abdullah, Abu S; Yang, Li
2015-11-01
This study aimed to assess the relationships between road traffic injury severity and individual characteristics in Liuzhou, a city in southern China. Data for this study were collected from the Guangxi Public Security Bureau Traffic Police Corps. Multivariate ordinal logistic regression analysis was used. Of all 14,595 individuals involved in accidents, males, motor vehicle drivers, motorcyclists, and those aged 21-45 years accounted for the great proportion of all injuries. Children, the elderly, pedestrians, farmers and migrant workers, unemployed people, and novice drivers were at higher risk of serious injury in crashes. These findings suggest that individual characteristics (age, modes of transport, profession, driving experience) are strongly related to injury severity. To address road traffic related mortality and injuries, there is a need to develop policy strategies, strengthen road supervision, and improve public consciousness of road safety.
The added value of ordinal analysis in clinical trials: an example in traumatic brain injury.
Roozenbeek, Bob; Lingsma, Hester F; Perel, Pablo; Edwards, Phil; Roberts, Ian; Murray, Gordon D; Maas, Andrew Ir; Steyerberg, Ewout W
2011-01-01
In clinical trials, ordinal outcome measures are often dichotomized into two categories. In traumatic brain injury (TBI) the 5-point Glasgow outcome scale (GOS) is collapsed into unfavourable versus favourable outcome. Simulation studies have shown that exploiting the ordinal nature of the GOS increases chances of detecting treatment effects. The objective of this study is to quantify the benefits of ordinal analysis in the real-life situation of a large TBI trial. We used data from the CRASH trial that investigated the efficacy of corticosteroids in TBI patients (n = 9,554). We applied two techniques for ordinal analysis: proportional odds analysis and the sliding dichotomy approach, where the GOS is dichotomized at different cut-offs according to baseline prognostic risk. These approaches were compared to dichotomous analysis. The information density in each analysis was indicated by a Wald statistic. All analyses were adjusted for baseline characteristics. Dichotomous analysis of the six-month GOS showed a non-significant treatment effect (OR = 1.09, 95% CI 0.98 to 1.21, P = 0.096). Ordinal analysis with proportional odds regression or sliding dichotomy showed highly statistically significant treatment effects (OR 1.15, 95% CI 1.06 to 1.25, P = 0.0007 and 1.19, 95% CI 1.08 to 1.30, P = 0.0002), with 2.05-fold and 2.56-fold higher information density compared to the dichotomous approach respectively. Analysis of the CRASH trial data confirmed that ordinal analysis of outcome substantially increases statistical power. We expect these results to hold for other fields of critical care medicine that use ordinal outcome measures and recommend that future trials adopt ordinal analyses. This will permit detection of smaller treatment effects.
The Outlier Detection for Ordinal Data Using Scalling Technique of Regression Coefficients
NASA Astrophysics Data System (ADS)
Adnan, Arisman; Sugiarto, Sigit
2017-06-01
The aims of this study is to detect the outliers by using coefficients of Ordinal Logistic Regression (OLR) for the case of k category responses where the score from 1 (the best) to 8 (the worst). We detect them by using the sum of moduli of the ordinal regression coefficients calculated by jackknife technique. This technique is improved by scalling the regression coefficients to their means. R language has been used on a set of ordinal data from reference distribution. Furthermore, we compare this approach by using studentised residual plots of jackknife technique for ANOVA (Analysis of Variance) and OLR. This study shows that the jackknifing technique along with the proper scaling may lead us to reveal outliers in ordinal regression reasonably well.
25 CFR 522.2 - Submission requirements.
Code of Federal Regulations, 2010 CFR
2010-04-01
... NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.2 Submission requirements. A tribe... officials and key employees; (d) Copies of all tribal gaming regulations; (e) When an ordinance or...
Cable Television Report and Suggested Ordinance.
ERIC Educational Resources Information Center
League of California Cities, Sacramento.
Guidelines and suggested ordinances for cable television regulation by local governments are comprehensively discussed in this report. The emphasis is placed on franchising the cable operator. Seventeen legal aspects of franchising are reviewed, and an exemplary ordinance is presented. In addition, current statistics about cable franchising in…
Borton, J
1996-12-01
This paper examines the co-ordination strategies developed to respond to the Great Lakes crisis following the events of April 1994. It analyses the different functions and mechanisms which sought to achieve a co-ordinated response--ranging from facilitation at one extreme to management and direction at the other. The different regimes developed to facilitate co-ordination within Rwanda and neighbouring countries, focusing on both inter-agency and inter-country co-ordination issues, are then analysed. Finally, the paper highlights the absence of mechanisms to achieve coherence between the humanitarian, political and security domains. It concludes that effective co-ordination is critical not only to achieve programme efficiency, but to ensure that the appropriate instruments and strategies to respond to complex political emergencies are in place. It proposes a radical re-shaping of international humanitarian, political and security institutions, particularly the United Nations, to improve the effectiveness of humanitarian and political responses to crises such as that in the Great Lakes.
No toy for you! The healthy food incentives ordinance: paternalism or consumer protection?
Etow, Alexis M
2012-01-01
The newest approach to discouraging children's unhealthy eating habits, amidst increasing rates of childhood obesity and other diet-related diseases, seeks to ban something that is not even edible. In 2010, San Francisco enacted the Healthy Food Incentives Ordinance, which prohibits toys in kids' meals if the meals do not meet certain nutritional requirements. Notwithstanding the Ordinance's impact on interstate commerce or potential infringement on companies' commercial speech rights and on parents' rights to determine what their children eat, this Comment argues that the Ordinance does not violate the dormant Commerce Clause, the First Amendment, or substantive due process. The irony is that although the Ordinance likely avoids the constitutional hurdles that hindered earlier measures aimed at childhood obesity, it intrudes on civil liberties more than its predecessors. This Comment analyzes the legality of the Healthy Food Incentives Ordinance to understand its implications on subsequent legislation aimed at combating childhood obesity and on the progression of public health law.
Order-constrained linear optimization.
Tidwell, Joe W; Dougherty, Michael R; Chrabaszcz, Jeffrey S; Thomas, Rick P
2017-11-01
Despite the fact that data and theories in the social, behavioural, and health sciences are often represented on an ordinal scale, there has been relatively little emphasis on modelling ordinal properties. The most common analytic framework used in psychological science is the general linear model, whose variants include ANOVA, MANOVA, and ordinary linear regression. While these methods are designed to provide the best fit to the metric properties of the data, they are not designed to maximally model ordinal properties. In this paper, we develop an order-constrained linear least-squares (OCLO) optimization algorithm that maximizes the linear least-squares fit to the data conditional on maximizing the ordinal fit based on Kendall's τ. The algorithm builds on the maximum rank correlation estimator (Han, 1987, Journal of Econometrics, 35, 303) and the general monotone model (Dougherty & Thomas, 2012, Psychological Review, 119, 321). Analyses of simulated data indicate that when modelling data that adhere to the assumptions of ordinary least squares, OCLO shows minimal bias, little increase in variance, and almost no loss in out-of-sample predictive accuracy. In contrast, under conditions in which data include a small number of extreme scores (fat-tailed distributions), OCLO shows less bias and variance, and substantially better out-of-sample predictive accuracy, even when the outliers are removed. We show that the advantages of OCLO over ordinary least squares in predicting new observations hold across a variety of scenarios in which researchers must decide to retain or eliminate extreme scores when fitting data. © 2017 The British Psychological Society.
NASA Astrophysics Data System (ADS)
Bezruczko, N.; Stanley, T.; Battle, M.; Latty, C.
2016-11-01
Despite broad sweeping pronouncements by international research organizations that social sciences are being integrated into global research programs, little attention has been directed toward obstacles blocking productive collaborations. In particular, social sciences routinely implement nonlinear, ordinal measures, which fundamentally inhibit integration with overarching scientific paradigms. The widely promoted general linear model in contemporary social science methods is largely based on untransformed scores and ratings, which are neither objective nor linear. This issue has historically separated physical and social sciences, which this report now asserts is unnecessary. In this research, nonlinear, subjective caregiver ratings of confidence to care for children supported by complex, medical technologies were transformed to an objective scale defined by logits (N=70). Transparent linear units from this transformation provided foundational insights into measurement properties of a social- humanistic caregiving construct, which clarified physical and social caregiver implications. Parameterized items and ratings were also subjected to multivariate hierarchical analysis, then decomposed to demonstrate theoretical coherence (R2 >.50), which provided further support for convergence of mathematical parameterization, physical expectations, and a social-humanistic construct. These results present substantial support for improving integration of social sciences with contemporary scientific research programs by emphasizing construction of common variables with objective, linear units.
Van Cann, Joannes; Virgilio, Massimiliano; Jordaens, Kurt; De Meyer, Marc
2015-01-01
Previous attempts to resolve the Ceratitis FAR complex (Ceratitis fasciventris, Ceratitis anonae, Ceratitis rosa, Diptera, Tephritidae) showed contrasting results and revealed the occurrence of five microsatellite genotypic clusters (A, F1, F2, R1, R2). In this paper we explore the potential of wing morphometrics for the diagnosis of FAR morphospecies and genotypic clusters. We considered a set of 227 specimens previously morphologically identified and genotyped at 16 microsatellite loci. Seventeen wing landmarks and 6 wing band areas were used for morphometric analyses. Permutational multivariate analysis of variance detected significant differences both across morphospecies and genotypic clusters (for both males and females). Unconstrained and constrained ordinations did not properly resolve groups corresponding to morphospecies or genotypic clusters. However, posterior group membership probabilities (PGMPs) of the Discriminant Analysis of Principal Components (DAPC) allowed the consistent identification of a relevant proportion of specimens (but with performances differing across morphospecies and genotypic clusters). This study suggests that wing morphometrics and PGMPs might represent a possible tool for the diagnosis of species within the FAR complex. Here, we propose a tentative diagnostic method and provide a first reference library of morphometric measures that might be used for the identification of additional and unidentified FAR specimens.
A coordinated MIMO control design for a power plant using improved sliding mode controller.
Ataei, Mohammad; Hooshmand, Rahmat-Allah; Samani, Siavash Golmohammadi
2014-03-01
For the participation of the steam power plants in regulating the network frequency, boilers and turbines should be co-ordinately controlled in addition to the base load productions. Lack of coordinated control over boiler-turbine may lead to instability; oscillation in producing power and boiler parameters; reduction in the reliability of the unit; and inflicting thermodynamic tension on devices. This paper proposes a boiler-turbine coordinated multivariable control system based on improved sliding mode controller (ISMC). The system controls two main boiler-turbine parameters i.e., the turbine revolution and superheated steam pressure of the boiler output. For this purpose, a comprehensive model of the system including complete and exact description of the subsystems is extracted. The parameters of this model are determined according to our case study that is the 320MW unit of Islam-Abad power plant in Isfahan/Iran. The ISMC method is simulated on the power plant and its performance is compared with the related real PI (proportional-integral) controllers which have been used in this unit. The simulation results show the capability of the proposed controller system in controlling local network frequency and superheated steam pressure in the presence of load variations and disturbances of boiler. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.
Taylor, Jeremy M G; Conlon, Anna S C; Elliott, Michael R
2015-08-01
The validation of intermediate markers as surrogate markers (S) for the true outcome of interest (T) in clinical trials offers the possibility for trials to be run more quickly and cheaply by using the surrogate endpoint in place of the true endpoint. Working within a principal stratification framework, we propose causal quantities to evaluate surrogacy using a Gaussian copula model for an ordinal surrogate and time-to-event final outcome. The methods are applied to data from four colorectal cancer clinical trials, where S is tumor response and T is overall survival. For the Gaussian copula model, a Bayesian estimation strategy is used and, as some parameters are not identifiable from the data, we explore the use of informative priors that are consistent with reasonable assumptions in the surrogate marker setting to aid in estimation. While there is some bias in the estimation of the surrogacy quantities of interest, the estimation procedure does reasonably well at distinguishing between poor and good surrogate markers. Some of the parameters of the proposed model are not identifiable from the data, and therefore, assumptions must be made in order to aid in their estimation. The proposed quantities can be used in combination to provide evidence about the validity of S as a surrogate marker for T. © The Author(s) 2014.
Chakravorty, Subhajit; Grandner, Michael A.; Mavandadi, Shahrzad; Perlis, Michael L.; Sturgis, Elliott B.; Oslin, David W.
2015-01-01
Objective The aim of this investigation was to assess the relationships between suicidal ideation and insomnia symptoms in Veterans misusing alcohol. Method Data were extracted in this retrospective chart review of Veterans referred from primary care for a behavioral health evaluation (N = 161) based on evidence of heavy drinking, drug use or another behavioral problem. Suicidal ideation (SI) was assessed using the Paykel questionnaire. Insomnia symptoms were assessed with standard diary questions in an interview format and pertained to sleep latency (SL), wake after sleep onset time (WASO), sleep quality (SQ), and habitual sleep duration (HSD). The relations between suicidal ideation and insomnia symptoms were assessed using ordinal regression analyses adjusted for socio-demographic, psychiatric and addiction-related variables. Results Suicidal ideation was reported in 62 (39%) of the Veterans interviewed. In a multivariable model, only inadequate SQ was associated with suicidal ideation. Short sleepers were more likely to endorse suicidal ideation and have attempted suicide in the past year. In addition, older age, inadequate financial status, and the presence of a psychiatric disorder were also significantly associated with suicidal ideation in most of the adjusted models. Conclusion Given their association with suicidal ideation, insomnia symptoms in Veterans misusing alcohol should prompt an assessment of underlying psychiatric and social factors. PMID:24169371
Salomon, Joshua A
2003-01-01
Background In survey studies on health-state valuations, ordinal ranking exercises often are used as precursors to other elicitation methods such as the time trade-off (TTO) or standard gamble, but the ranking data have not been used in deriving cardinal valuations. This study reconsiders the role of ordinal ranks in valuing health and introduces a new approach to estimate interval-scaled valuations based on aggregate ranking data. Methods Analyses were undertaken on data from a previously published general population survey study in the United Kingdom that included rankings and TTO values for hypothetical states described using the EQ-5D classification system. The EQ-5D includes five domains (mobility, self-care, usual activities, pain/discomfort and anxiety/depression) with three possible levels on each. Rank data were analysed using a random utility model, operationalized through conditional logit regression. In the statistical model, probabilities of observed rankings were related to the latent utilities of different health states, modeled as a linear function of EQ-5D domain scores, as in previously reported EQ-5D valuation functions. Predicted valuations based on the conditional logit model were compared to observed TTO values for the 42 states in the study and to predictions based on a model estimated directly from the TTO values. Models were evaluated using the intraclass correlation coefficient (ICC) between predictions and mean observations, and the root mean squared error of predictions at the individual level. Results Agreement between predicted valuations from the rank model and observed TTO values was very high, with an ICC of 0.97, only marginally lower than for predictions based on the model estimated directly from TTO values (ICC = 0.99). Individual-level errors were also comparable in the two models, with root mean squared errors of 0.503 and 0.496 for the rank-based and TTO-based predictions, respectively. Conclusions Modeling health-state valuations based on ordinal ranks can provide results that are similar to those obtained from more widely analyzed valuation techniques such as the TTO. The information content in aggregate ranking data is not currently exploited to full advantage. The possibility of estimating cardinal valuations from ordinal ranks could also simplify future data collection dramatically and facilitate wider empirical study of health-state valuations in diverse settings and population groups. PMID:14687419
Using an Ordinal Outranking Method Supporting the Acquisition of Military Equipment
2009-10-01
will concentrate on the well-known ORESTE method ([10],[12]) which is complementary to the PROMETHEE methods. There are other methods belonging to...the PROMETHEE methods. This MCDM method is taught in the curriculum of the High Staff College for Military Administrators of the Belgian MoD...C(b,a) similar to the preference indicators ( , ) and (b,a)a b of the PROMETHEE methods (see [4] and SAS-080 14 and SAS-080 15). These
77 FR 34981 - Stillaguamish Tribe of Indians-Liquor Control Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-12
... DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs Stillaguamish Tribe of Indians--Liquor Control... publishes the Stillaguamish Tribe of Indians' Liquor Control Ordinance. The Ordinance regulates and controls... of the Stillaguamish Tribe of Indians, will increase the ability of the tribal government to control...
7 CFR 1901.204 - Compliance reviews.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Administrator, Community and Business Programs, for each recipient. (4) Mandatory hook-up ordinance. Compliance... under the provisions of a mandatory hook-up ordinance will consist of a certification by the borrower or grantee that the ordinance is still in effect and is being enforced. (5) Forwarding noncompliance report...
7 CFR 1901.204 - Compliance reviews.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Administrator, Community and Business Programs, for each recipient. (4) Mandatory hook-up ordinance. Compliance... under the provisions of a mandatory hook-up ordinance will consist of a certification by the borrower or grantee that the ordinance is still in effect and is being enforced. (5) Forwarding noncompliance report...
7 CFR 1901.204 - Compliance reviews.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Administrator, Community and Business Programs, for each recipient. (4) Mandatory hook-up ordinance. Compliance... under the provisions of a mandatory hook-up ordinance will consist of a certification by the borrower or grantee that the ordinance is still in effect and is being enforced. (5) Forwarding noncompliance report...
7 CFR 1901.204 - Compliance reviews.
Code of Federal Regulations, 2013 CFR
2013-01-01
... Administrator, Community and Business Programs, for each recipient. (4) Mandatory hook-up ordinance. Compliance... under the provisions of a mandatory hook-up ordinance will consist of a certification by the borrower or grantee that the ordinance is still in effect and is being enforced. (5) Forwarding noncompliance report...
Access to cigarettes by daily smokers in Florida's public middle schools and high schools.
Saunders, Charles
2011-07-01
Youth who smoke daily have diverse methods for obtaining cigarettes, which range from commercial sources to essentially black market transactions. This study examines access to cigarettes, attitudes toward tobacco, and the demographic characteristics of youth who are daily cigarette smokers. Biennial data from the Florida Youth Tobacco Survey, a representative sample of Florida public middle- and high-school students, were used. Daily smoking was categorized into ordinal categories of increasing intensity. Analysis was done with a logistic partial proportional odds model, which allowed the effects of the independent predictors to vary according to smoking intensity. The multivariate analysis revealed that males and females have different methods of obtaining cigarettes. Moreover, certain modes of access to cigarettes were related to daily smoking intensity. Males who obtained cigarettes from their parents or stole them from a store were much more likely to have a higher intensity of daily smoking. Females who gave someone money to buy their cigarettes or bought them from a person were more likely to smoke more cigarettes per day. Males, but not females, also perceived that increasing the number of cigarettes smoked per day provides social benefits in the form of more friends. Understanding how daily youth smokers obtain cigarettes is necessary if effective antitobacco policies are to be developed for these individuals. Daily youth smokers are at increased risk of becoming addicted to nicotine, making them more likely to transition to daily adult smoking.
2011-01-01
Background Pesticide use on urban lawns and gardens contributes to environmental contamination and human exposure. Municipal policies to restrict use and educate households on viable alternatives deserve study. We describe the development and implementation of a cosmetic/non-essential pesticide bylaw by a municipal health department in Toronto, Ontario, Canada and assess changes in resident practices associated with bylaw implementation. Methods Implementation indicators built on a logic model and were elaborated through key informant interviews. Bylaw impacts on awareness and practice changes were documented through telephone surveys administered seasonally pre, during and post implementation (2003-2008). Multivariable logistic regression models assessed associations of demographic variables and gardening season with respondent awareness and practices. Results Implementation indicators documented multiple municipal health department activities and public involvement in complaints from commencement of the educational phase. During the enforcement phases only 40 warning letters and 7 convictions were needed. The number of lawn care companies increased. Among survey respondents, awareness of the bylaw and the Natural Lawn campaign reached 69% and 76% respectively by 2008. Substantial decreases in the proportion of households applying pesticides (25 to 11%) or hiring lawn care companies for application (15 to 5%) occurred. Parallel absolute increases in use of natural lawn care methods occurred among households themselves (21%) and companies they contracted (7%). Conclusions Bylaws or ordinances implemented through education and enforcement are a viable policy option for reducing urban cosmetic pesticide use. PMID:21867501
Bigoni, L; Velemínská, J; Brůzek, J
2010-02-01
This article presents an approach for estimating the sexual dimorphism of adult crania using three-dimensional geometric morphometric methods. The study sample consisted of 139 crania of known sex (73 males and 66 females) belonging to persons who lived during the first half of the 20th century in Bohemia. The three-dimensional co-ordinates of 82 ecto-cranial landmarks and 39 semi-landmarks covering the midsagittal curve of the cranial vault were digitised using a MicroScribe G2X contact digitiser. The purposes of the investigation were to define the regions of the cranium where sexual dimorphism is most pronounced and to investigate the effectiveness of this method for determining sex from the shape of the cranium. The results demonstrate that it is better to analyse apportionable parts of the cranium rather than the cranium as a whole. Significant sexual differences (significance was determined using multivariate analysis of variance) were noted in the shape of the midsagittal curve of the vault, upper face, the region of the nose, orbits, and palate. No differences were recorded either in the shape of the cranium as a whole or in the regions of the base and the neurocranium. The greatest accuracy in determining sex was found in the region of the upper face (100% of study subjects correctly classified) and the midsagittal curve of the vault (99% of study subjects correctly classified). Copyright (c) 2010 Elsevier GmbH. All rights reserved.
Why Multivariate Methods Are Usually Vital in Research: Some Basic Concepts.
ERIC Educational Resources Information Center
Thompson, Bruce
The present paper suggests that multivariate methods ought to be used more frequently in behavioral research and explores the potential consequences of failing to use multivariate methods when these methods are appropriate. The paper explores in detail two reasons why multivariate methods are usually vital. The first is that they limit the…
DOT National Transportation Integrated Search
1990-10-01
In the absence of a statewide law, a local ordinance was passed by the Lexington-Fayette Urban County Government mandating use of safety belts. The objective of this study was to conduct surveys before the ordinance was passed, during the implementat...
Cardination and Ordination Learning in Young Children.
ERIC Educational Resources Information Center
Stock, William; Flora, June
This paper analyzes Brainerd's work in assessing the developmental sequence or ordination and cardination concepts of number, and describes a study which investigated the hypothesis that task-specific difficulty could explain Brainers's data. Three new tasks were designed for the assessment of ordination and cardination and administered to a…
25 CFR 522.6 - Approval requirements for class III ordinances.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Section 522.6 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.6 Approval...) The tribe shall have the sole proprietary interest in and responsibility for the conduct of any gaming...
36 CFR 28.15 - Approval of local zoning ordinances.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Approval of local zoning ordinances. 28.15 Section 28.15 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR FIRE ISLAND NATIONAL SEASHORE: ZONING STANDARDS Federal Standards and Approval of Local Ordinances...
Bayesian Adaptive Lasso for Ordinal Regression with Latent Variables
ERIC Educational Resources Information Center
Feng, Xiang-Nan; Wu, Hao-Tian; Song, Xin-Yuan
2017-01-01
We consider an ordinal regression model with latent variables to investigate the effects of observable and latent explanatory variables on the ordinal responses of interest. Each latent variable is characterized by correlated observed variables through a confirmatory factor analysis model. We develop a Bayesian adaptive lasso procedure to conduct…
36 CFR 28.15 - Approval of local zoning ordinances.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Approval of local zoning ordinances. 28.15 Section 28.15 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR FIRE ISLAND NATIONAL SEASHORE: ZONING STANDARDS Federal Standards and Approval of Local Ordinances...
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Do tribal employment rights ordinances apply to... OF THE INTERIOR, AND INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES CONTRACTS UNDER... rights ordinances apply to construction contracts and subcontracts? Yes. Tribal employment rights...
Tsoukalas, Theodore; Glantz, Stanton A.
2003-01-01
Case study methodology was used to investigate the tobacco industry’s strategies to fight local tobacco control efforts in Duluth, Minn. The industry opposed the clean indoor air ordinance indirectly through allies and front groups and directly in a referendum. Health groups failed to win a strong ordinance because they framed it as a youth issue rather than a workplace issue and failed to engage the industry’s economic claims. Opponents’ overexploitation of weaknesses in the ordinance allowed health advocates to construct a stronger version. Health advocates should assume that the tobacco industry will oppose all local tobacco control measures indirectly, directly, or both. Clean indoor air ordinances should be framed as workplace safety issues. PMID:12893598
Environmental Gradient Analysis, Ordination, and Classification in Environmental Impact Assessments.
1987-09-01
agglomerative clustering algorithms for mainframe computers: (1) the unweighted pair-group method that V uses arithmetic averages ( UPGMA ), (2) the...hierarchical agglomerative unweighted pair-group method using arithmetic averages ( UPGMA ), which is also called average linkage clustering. This method was...dendrograms produced by weighted clustering (93). Sneath and Sokal (94), Romesburg (84), and Seber• (90) also strongly recommend the UPGMA . A dendrogram
Appropriate Statistical Analysis for Two Independent Groups of Likert-Type Data
ERIC Educational Resources Information Center
Warachan, Boonyasit
2011-01-01
The objective of this research was to determine the robustness and statistical power of three different methods for testing the hypothesis that ordinal samples of five and seven Likert categories come from equal populations. The three methods are the two sample t-test with equal variances, the Mann-Whitney test, and the Kolmogorov-Smirnov test. In…
Rapid field-based protocols for classifying flow permanence of headwater streams are needed to inform timely regulatory decisions. Such an existing method was developed for and has been used in North Carolina since 1997. The method uses ordinal scoring of 26 geomorphology, hydr...
Li, Haitao; Wei, Xiaolin; Wong, Martin Chi-Sang; Wong, Samuel Yeung-Shan; Yang, Nan; Griffiths, Sian M.
2015-01-01
Abstract Hypertension should be best managed under primary care settings. This study aimed to compare, between Shanghai and Shenzhen, the perceived quality of primary care in terms of accessibility, continuity, co-ordination, and comprehensiveness among hypertensive patients. A cross-sectional study was conducted in Shanghai and Shenzhen, China. Multistage random sampling method was used to select 8 community health centers. Data from primary care users were collected through on-site face-to-face interviews using the primary care assessment tool. Good quality standard was set as a value of 3 for each attribute and a value of 18 for total score. We included 568 patients in Shanghai and 128 patients in Shenzhen. Compared with those in Shenzhen, hypertensive patients in Shanghai reported a higher score in co-ordination of information (3.37 vs 3.66; P < 0.001), but lower scores in continuity of care (3.36 vs 3.27; P < 0.001), and comprehensiveness-service provision (3.26 vs 2.79; P < 0.001). There was no statistically significant difference in total scores between the 2 cities (18.19 vs 18.15). Over 3-quarters of hypertensive patients in both cities reported accessibility (97.2% vs 91.4%) and co-ordination of services (76.1% vs 80.5%) under good quality standard, while <1-quarter of them rated continuity of care (23.6% vs 22.7%), co-ordination of information (4.8% vs 21.1%), and comprehensiveness-service availability (15.1% vs 25.0%) under that standard. Compared with Shenzhen, the perceived quality of primary care for hypertensive patients in Shanghai was better in terms of co-ordination of information, but poorer on continuity of care and comprehensiveness-service provision. Our study suggests that there is room for quality improvement in both cities. PMID:26313780
Brown, Brandon; Wachowiak-Smolíková, Renata; Spence, Nicholas D.; Wachowiak, Mark P.; Walters, Dan F.
2016-01-01
Securing safe and adequate drinking water is an ongoing issue for many Canadian First Nations communities despite nearly 15 years of reports, studies, policy changes, financial commitments, and regulations. The federal drinking water evaluation scheme is narrowly scoped, ignoring community level social factors, which may play a role in access to safe water in First Nations. This research used the 2006 Aboriginal Affairs and Northern Development Canada First Nations Drinking Water System Risk Survey data and the Community Well-Being Index, including labour force, education, housing, and income, from the 2006 Census. Bivariate analysis was conducted using the Spearman’s correlation, Kendall’s tau correlation, and Pearson’s correlation. Multivariable analysis was conducted using an ordinal (proportional or cumulative odds) regression model. Results showed that the regression model was significant. Community socioeconomic indicators had no relationship with drinking water risk characterization in both the bivariate and multivariable models, with the sole exception of labour force, which had a significantly positive effect on drinking water risk rankings. Socioeconomic factors were not important in explaining access to safe drinking water in First Nations communities. Improvements in the quality of safe water data as well as an examination of other community processes are required to address this pressing policy issue. PMID:27157172
Brown, Brandon; Wachowiak-Smolíková, Renata; Spence, Nicholas D; Wachowiak, Mark P; Walters, Dan F
2016-09-01
Securing safe and adequate drinking water is an ongoing issue for many Canadian First Nations communities despite nearly 15 years of reports, studies, policy changes, financial commitments, and regulations. The federal drinking water evaluation scheme is narrowly scoped, ignoring community level social factors, which may play a role in access to safe water in First Nations. This research used the 2006 Aboriginal Affairs and Northern Development Canada First Nations Drinking Water System Risk Survey data and the Community Well-Being Index, including labour force, education, housing, and income, from the 2006 Census. Bivariate analysis was conducted using the Spearman's correlation, Kendall's tau correlation, and Pearson's correlation. Multivariable analysis was conducted using an ordinal (proportional or cumulative odds) regression model. Results showed that the regression model was significant. Community socioeconomic indicators had no relationship with drinking water risk characterization in both the bivariate and multivariable models, with the sole exception of labour force, which had a significantly positive effect on drinking water risk rankings. Socioeconomic factors were not important in explaining access to safe drinking water in First Nations communities. Improvements in the quality of safe water data as well as an examination of other community processes are required to address this pressing policy issue.
Yount, Kathryn M; Krause, Kathleen H
2017-01-01
To provide the first study in Vietnam of how gendered social learning about violence and exposure to non-family institutions influence women's attitudes about a wife's recourse after physical IPV. A probability sample of 532 married women, ages 18-50 years, was surveyed in July-August, 2012 in Mỹ Hào district. We fit a multivariate linear regression model to estimate correlates of favoring recourse in six situations using a validated attitudinal scale. We split attitudes towards recourse into three subscales (disfavor silence, favor informal recourse, favor formal recourse) and fit one multivariate ordinal logistic regression model for each behavior to estimate correlates of favoring recourse. On average, women favored recourse in 2.8 situations. Women who were older and had witnessed physical IPV in childhood had less favorable attitudes about recourse. Women who were hit as children, had completed more schooling, worked outside agriculture, and had sought recourse after IPV had more favorable attitudes about recourse. Normative change among women may require efforts to curb family violence, counsel those exposed to violence in childhood, and enhance women's opportunities for higher schooling and non-agricultural wage work. The state and organizations working on IPV might overcome pockets of unfavorable public opinion by enforcing accountability for IPV rather than seeking to alter ideas about recourse among women.
ERIC Educational Resources Information Center
Kaufmann, L.; Vogel, S. E.; Starke, M.; Kremser, C.; Schocke, M.
2009-01-01
Ordinality is--beyond numerical magnitude (i.e., quantity)--an important characteristic of the number system. There is converging empirical evidence that (intra)parietal brain regions mediate number magnitude processing. Furthermore, recent findings suggest that the human intraparietal sulcus (IPS) supports magnitude and ordinality in a…
25 CFR 522.1 - Scope of this part.
Code of Federal Regulations, 2010 CFR
2010-04-01
... INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.1 Scope of this part. This part applies to any gaming ordinance or resolution adopted by a tribe after February 22, 1993. Part 523 of this chapter...
Land and Liberty: The Ordinances of the 1780s.
ERIC Educational Resources Information Center
Sheehan, Bernard W.
The U.S. Constitution established the broad legal frame for the U.S. political order; the ordinances provided the indispensable means for the expansion of that order across the continent. The first effort at organizing the northwest occurred in 1784. Written by Thomas Jefferson, the Ordinance of 1784 defined the stages through which territories…
Educational Legislation in Colonial Zimbabwe (1899-1979)
ERIC Educational Resources Information Center
Richards, Kimberly; Govere, Ephraim
2003-01-01
This article focuses on a historical series of education acts that impacted on education in Rhodesia. These Acts are the: (1) 1899 Education Ordinance; (2) 1903 Education Ordinance; (3) 1907 Education Ordinance; (4) 1929 Department of Native Development Act; (5) 1930 Compulsory Education Act; (6) 1959 African Education Act; (7) 1973 Education Act;…
Steil, Justin Peter; Vasi, Ion Bogdan
2014-01-01
Analyzing oppositional social movements in the context of municipal immigration ordinances, the authors examine whether the explanatory power of resource mobilization, political process, and strain theories of social movements' impact on policy outcomes differs when considering proactive as opposed to reactive movements. The adoption of pro-immigrant (proactive) ordinances was facilitated by the presence of immigrant community organizations and of sympathetic local political allies. The adoption of anti-immigrant (reactive) ordinances was influenced by structural social changes, such as rapid increases in the local Latino population, that were framed as threats. The study also finds that pro-immigrant protest events can influence policy in two ways, contributing both to the passage of pro-immigrant ordinances in the locality where protests occur and also inhibiting the passage of anti-immigrant ordinances in neighboring cities.
NASA Astrophysics Data System (ADS)
Kitzmann, D.; Patzer, A. B. C.; Rauer, H.
2013-09-01
Context. Owing to their wavelength-dependent absorption and scattering properties, clouds have a strong impact on the climate of planetary atmospheres. The potential greenhouse effect of CO2 ice clouds in the atmospheres of terrestrial extrasolar planets is of particular interest because it might influence the position and thus the extension of the outer boundary of the classic habitable zone around main sequence stars. Such a greenhouse effect, however, is a complicated function of the CO2 ice particles' optical properties. Aims: We study the radiative effects of CO2 ice particles obtained by different numerical treatments to solve the radiative transfer equation. To determine the effectiveness of the scattering greenhouse effect caused by CO2 ice clouds, the radiative transfer calculations are performed over the relevant wide range of particle sizes and optical depths, employing different numerical methods. Methods: We used Mie theory to calculate the optical properties of particle polydispersion. The radiative transfer calculations were done with a high-order discrete ordinate method (DISORT). Two-stream radiative transfer methods were used for comparison with previous studies. Results: The comparison between the results of a high-order discrete ordinate method and simpler two-stream approaches reveals large deviations in terms of a potential scattering efficiency of the greenhouse effect. The two-stream methods overestimate the transmitted and reflected radiation, thereby yielding a higher scattering greenhouse effect. For the particular case of a cool M-type dwarf, the CO2 ice particles show no strong effective scattering greenhouse effect by using the high-order discrete ordinate method, whereas a positive net greenhouse effect was found for the two-stream radiative transfer schemes. As a result, previous studies of the effects of CO2 ice clouds using two-stream approximations overrated the atmospheric warming caused by the scattering greenhouse effect. Consequently, the scattering greenhouse effect of CO2 ice particles seems to be less effective than previously estimated. In general, higher order radiative transfer methods are needed to describe the effects of CO2 ice clouds accurately as indicated by our numerical radiative transfer studies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Le Hardy, D.; Favennec, Y., E-mail: yann.favennec@univ-nantes.fr; Rousseau, B.
The contribution of this paper relies in the development of numerical algorithms for the mathematical treatment of specular reflection on borders when dealing with the numerical solution of radiative transfer problems. The radiative transfer equation being integro-differential, the discrete ordinates method allows to write down a set of semi-discrete equations in which weights are to be calculated. The calculation of these weights is well known to be based on either a quadrature or on angular discretization, making the use of such method straightforward for the state equation. Also, the diffuse contribution of reflection on borders is usually well taken intomore » account. However, the calculation of accurate partition ratio coefficients is much more tricky for the specular condition applied on arbitrary geometrical borders. This paper presents algorithms that calculate analytically partition ratio coefficients needed in numerical treatments. The developed algorithms, combined with a decentered finite element scheme, are validated with the help of comparisons with analytical solutions before being applied on complex geometries.« less
Posterior Predictive Bayesian Phylogenetic Model Selection
Lewis, Paul O.; Xie, Wangang; Chen, Ming-Hui; Fan, Yu; Kuo, Lynn
2014-01-01
We present two distinctly different posterior predictive approaches to Bayesian phylogenetic model selection and illustrate these methods using examples from green algal protein-coding cpDNA sequences and flowering plant rDNA sequences. The Gelfand–Ghosh (GG) approach allows dissection of an overall measure of model fit into components due to posterior predictive variance (GGp) and goodness-of-fit (GGg), which distinguishes this method from the posterior predictive P-value approach. The conditional predictive ordinate (CPO) method provides a site-specific measure of model fit useful for exploratory analyses and can be combined over sites yielding the log pseudomarginal likelihood (LPML) which is useful as an overall measure of model fit. CPO provides a useful cross-validation approach that is computationally efficient, requiring only a sample from the posterior distribution (no additional simulation is required). Both GG and CPO add new perspectives to Bayesian phylogenetic model selection based on the predictive abilities of models and complement the perspective provided by the marginal likelihood (including Bayes Factor comparisons) based solely on the fit of competing models to observed data. [Bayesian; conditional predictive ordinate; CPO; L-measure; LPML; model selection; phylogenetics; posterior predictive.] PMID:24193892
Flow analysis for efficient design of wavy structured microchannel mixing devices
NASA Astrophysics Data System (ADS)
Kanchan, Mithun; Maniyeri, Ranjith
2018-04-01
Microfluidics is a rapidly growing field of applied research which is strongly driven by demands of bio-technology and medical innovation. Lab-on-chip (LOC) is one such application which deals with integrating bio-laboratory on micro-channel based single fluidic chip. Since fluid flow in such devices is restricted to laminar regime, designing an efficient passive modulator to induce chaotic mixing for such diffusion based flow is a major challenge. In the present work two-dimensional numerical simulation of viscous incompressible flow is carried out using immersed boundary method (IBM) to obtain an efficient design for wavy structured micro-channel mixing devices. The continuity and Navier-Stokes equations governing the flow are solved by fractional step based finite volume method on a staggered Cartesian grid system. IBM uses Eulerian co-ordinates to describe fluid flow and Lagrangian co-ordinates to describe solid boundary. Dirac delta function is used to couple both these co-ordinate variables. A tether forcing term is used to impose the no-slip boundary condition on the wavy structure and fluid interface. Fluid flow analysis by varying Reynolds number is carried out for four wavy structure models and one straight line model. By analyzing fluid accumulation zones and flow velocities, it can be concluded that straight line structure performs better mixing for low Reynolds number and Model 2 for higher Reynolds number. Thus wavy structures can be incorporated in micro-channels to improve mixing efficiency.
Nelson, Kerrie P; Mitani, Aya A; Edwards, Don
2017-09-10
Widespread inconsistencies are commonly observed between physicians' ordinal classifications in screening tests results such as mammography. These discrepancies have motivated large-scale agreement studies where many raters contribute ratings. The primary goal of these studies is to identify factors related to physicians and patients' test results, which may lead to stronger consistency between raters' classifications. While ordered categorical scales are frequently used to classify screening test results, very few statistical approaches exist to model agreement between multiple raters. Here we develop a flexible and comprehensive approach to assess the influence of rater and subject characteristics on agreement between multiple raters' ordinal classifications in large-scale agreement studies. Our approach is based upon the class of generalized linear mixed models. Novel summary model-based measures are proposed to assess agreement between all, or a subgroup of raters, such as experienced physicians. Hypothesis tests are described to formally identify factors such as physicians' level of experience that play an important role in improving consistency of ratings between raters. We demonstrate how unique characteristics of individual raters can be assessed via conditional modes generated during the modeling process. Simulation studies are presented to demonstrate the performance of the proposed methods and summary measure of agreement. The methods are applied to a large-scale mammography agreement study to investigate the effects of rater and patient characteristics on the strength of agreement between radiologists. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Reliability of Total Test Scores When Considered as Ordinal Measurements
ERIC Educational Resources Information Center
Biswas, Ajoy Kumar
2006-01-01
This article studies the ordinal reliability of (total) test scores. This study is based on a classical-type linear model of observed score (X), true score (T), and random error (E). Based on the idea of Kendall's tau-a coefficient, a measure of ordinal reliability for small-examinee populations is developed. This measure is extended to large…
Economic Analysis of a Living Wage Ordinance.
ERIC Educational Resources Information Center
Tolley, George; Bernstein, Peter
A study estimated the costs of the "Chicago Jobs and Living Wage Ordinance" that would require firms that receive assistance from the city of Chicago to pay their workers an hourly wage of at least $7.60. An estimate of the additional labor cost that would result from the proposed Ordinance was calculated. Results of a survey of…
ERIC Educational Resources Information Center
Kirby, Amanda; Sugden, David; Beveridge, Sally; Edwards, Lisa; Edwards, Rachel
2008-01-01
Developmental co-ordination disorder (DCD) is a developmental disorder affecting motor co-ordination. The "Diagnostics Statistics Manual"--IV classification for DCD describes difficulties across a range of activities of daily living, impacting on everyday skills and academic performance in school. Recent evidence has shown that…
ERIC Educational Resources Information Center
Kirby, Amanda; Edwards, Lisa; Sugden, David; Rosenblum, Sara
2010-01-01
Developmental Co-ordination Disorder (DCD), also known as Dyspraxia in the United Kingdom (U.K.), is a developmental disorder affecting motor co-ordination. In the past this was regarded as a childhood disorder, however there is increasing evidence that a significant number of children will continue to have persistent difficulties into adulthood.…
How to Plan an Ordinance: An Outline and Some Examples.
ERIC Educational Resources Information Center
Cable Television Information Center, Washington, DC.
Designed for public officials who must make policy decisions concerning cable television, this booklet forms a checklist to ensure that all basic questions have been considered in drafting an ordinance. The purpose of a cable television ordinance is to develop a law listing the specifications and obligations that will govern the franchising of a…
25 CFR 11.108 - How are tribal ordinances affected by this part?
Code of Federal Regulations, 2014 CFR
2014-04-01
... 25 Indians 1 2014-04-01 2014-04-01 false How are tribal ordinances affected by this part? 11.108 Section 11.108 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Application; Jurisdiction § 11.108 How are tribal ordinances affected by...
25 CFR 11.108 - How are tribal ordinances affected by this part?
Code of Federal Regulations, 2013 CFR
2013-04-01
... 25 Indians 1 2013-04-01 2013-04-01 false How are tribal ordinances affected by this part? 11.108 Section 11.108 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Application; Jurisdiction § 11.108 How are tribal ordinances affected by...
25 CFR 11.108 - How are tribal ordinances affected by this part?
Code of Federal Regulations, 2012 CFR
2012-04-01
... 25 Indians 1 2012-04-01 2011-04-01 true How are tribal ordinances affected by this part? 11.108 Section 11.108 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Application; Jurisdiction § 11.108 How are tribal ordinances affected by...
25 CFR 11.108 - How are tribal ordinances affected by this part?
Code of Federal Regulations, 2011 CFR
2011-04-01
... 25 Indians 1 2011-04-01 2011-04-01 false How are tribal ordinances affected by this part? 11.108 Section 11.108 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Application; Jurisdiction § 11.108 How are tribal ordinances affected by...
An Algorithm for Converting Ordinal Scale Measurement Data to Interval/Ratio Scale
ERIC Educational Resources Information Center
Granberg-Rademacker, J. Scott
2010-01-01
The extensive use of survey instruments in the social sciences has long created debate and concern about validity of outcomes, especially among instruments that gather ordinal-level data. Ordinal-level survey measurement of concepts that could be measured at the interval or ratio level produce errors because respondents are forced to truncate or…
Resolving human object recognition in space and time
Cichy, Radoslaw Martin; Pantazis, Dimitrios; Oliva, Aude
2014-01-01
A comprehensive picture of object processing in the human brain requires combining both spatial and temporal information about brain activity. Here, we acquired human magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) responses to 92 object images. Multivariate pattern classification applied to MEG revealed the time course of object processing: whereas individual images were discriminated by visual representations early, ordinate and superordinate category levels emerged relatively later. Using representational similarity analysis, we combine human fMRI and MEG to show content-specific correspondence between early MEG responses and primary visual cortex (V1), and later MEG responses and inferior temporal (IT) cortex. We identified transient and persistent neural activities during object processing, with sources in V1 and IT., Finally, human MEG signals were correlated to single-unit responses in monkey IT. Together, our findings provide an integrated space- and time-resolved view of human object categorization during the first few hundred milliseconds of vision. PMID:24464044
Financial Conflicts of Interest and Study Results in Environmental and Occupational Health Research.
Friedman, Lee; Friedman, Michael
2016-03-01
To date, there is no comprehensive analysis of the relationship between financial conflict of interest (COI) and a potential publication bias in environmental and occupational health studies. We analyzed original research articles published in 2012 in 17 peer-reviewed journals. Multivariable ordinal logistic regression models were developed to evaluate the relationship between financial COI and the study outcome. Of the 373 studies included in the analysis, 17.2% had a financial COI associated with organizations involved with the processing, use, or disposal of industrial and commercial products, and studies with this type of COI were more likely to report negative results (Adjusted Odds Ratio = 4.31), as were studies with any COI associated with the military (employment or funding; Adjusted Odds Ratio = 9.15). Our findings show a clear relationship between direction of reported findings and specific types of financial COI.
Farias Júnior, José Cazuza de; Reis, Rodrigo Siqueira; Hallal, Pedro Curi
2014-05-01
The aim of this study was to evaluate the association between levels of physical activity, psychosocial and perceived environmental factors in adolescents from Northeastern Brazil. A cross-sectional epidemiologic study was conducted with 2,859 adolescents enrolled in secondary schools (57.8% females; mean = 16.5 years; SD = 1.2) in the city of João Pessoa, Paraíba State, Brazil. The following physical activity correlates were measured: attitude, self-efficacy, social support from friends and parents, and perceived environmental characteristics. Physical activity was measured using a questionnaire. Multivariable ordinal logistic regression with proportional odds model analysis showed that the following factors are positively related to physical activity levels in adolescents: attitude, self-efficacy, as well as social support from parents and friends. Physical activity intervention programs should increase self-efficacy and social support from parents and friends, as well as a positive attitude toward physical activity.
Mayo, Mariel Leah; Chriqui, Jamie F.
2013-01-01
Introduction Zoning ordinances and land-use plans may influence the community food environment by determining placement and access to food outlets, which subsequently support or hinder residents’ attempts to eat healthfully. The objective of this study was to examine associations between healthful food zoning scores as derived from information on local zoning ordinances, county demographics, and residents’ access to fruit and vegetable outlets in rural northeastern North Carolina. Methods From November 2012 through March 2013, county and municipality zoning ordinances were identified and double-coded by using the Bridging the Gap food code/policy audit form. A healthful food zoning score was derived by assigning points for the allowed use of fruit and vegetable outlets. Pearson coefficients were calculated to examine correlations between the healthful food zoning score, county demographics, and the number of fruit and vegetable outlets. In March and April 2013, qualitative interviews were conducted among county and municipal staff members knowledgeable about local zoning and planning to ascertain implementation and enforcement of zoning to support fruit and vegetable outlets. Results We found a strong positive correlation between healthful food zoning scores and the number of fruit and vegetable outlets in 13 northeastern North Carolina counties (r = 0.66, P = .01). Major themes in implementation and enforcement of zoning to support fruit and vegetable outlets included strict enforcement versus lack of enforcement of zoning regulations. Conclusion Increasing the range of permitted uses in zoning districts to include fruit and vegetable outlets may increase access to healthful fruit and vegetable outlets in rural communities. PMID:24309091
Starfish (Asteroidea, Echinodermata) from the Faroe Islands; spatial distribution and abundance
NASA Astrophysics Data System (ADS)
Ringvold, H.; Andersen, T.
2016-01-01
"Marine benthic fauna of the Faroe Islands" (BIOFAR) is a large programme with a focus on collecting invertebrate fauna from the Faroes (62°N and 7°W). Cruises were undertaken from 1987 to 1990, and starfish (Asteroidea, Echinodermata) collected during this time were analysed. Asteroidea were sampled at ~50% of all BIOFAR stations. A Detritus sledge and a Triangular dredge proved to be the most efficient equipment, collecting over 60% of the specimens. In total 2473 specimens were collected from 20 to 1500 m depth, including 41 species from 17 families and 31 genera. Henricia pertusa (O. F. Müller, 1776) group, Pontaster tenuispinus (Düben & Koren, 1846), and Leptychaster arcticus (M. Sars, 1851) showed highest relative abundance. Maximum species diversity was found at 500-700 m depth, which coincides with the transition zone of water masses (North Icelandic Winter Water and Arctic Intermediate Water (NI/AI)) at approximately 400-600 m depth. 63% of the species were recorded at an average-weighted depth above 600 m. Two different ordination methods (detrended correspondence analysis (DCA) and nonmetric multidimensional scaling (NMDS)) gave highly consistent representations of the community structure gradients. The first ordination axis scores did not show significant relationships with any environmental variable. Biological covariates like the presence of Lophelia corals were not significantly related to ordination scores on any axis. The second ordination axis scores were significantly correlated with depth. Temperature and salinity were highly correlated (r=0.90), and both negatively correlated with depth (r=-0.69 and r=-0.57, respectively).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vine, E.
1990-11-01
As part of Lawrence Berkeley Laboratory's (LBL) technical assistance to the Sustainable City Project, compliance and enforcement activities related to local and state building codes for existing and new construction were evaluated in two case studies. The analysis of the City of San Francisco's Residential Energy Conservation Ordinance (RECO) showed that a limited, prescriptive energy conservation ordinance for existing residential construction can be enforced relatively easily with little administrative costs, and that compliance with such ordinances can be quite high. Compliance with the code was facilitated by extensive publicity, an informed public concerned with the cost of energy and knowledgeablemore » about energy efficiency, the threat of punishment (Order of Abatement), the use of private inspectors, and training workshops for City and private inspectors. The analysis of California's Title 24 Standards for new residential and commercial construction showed that enforcement of this type of code for many climate zones is more complex and requires extensive administrative support for education and training of inspectors, architects, engineers, and builders. Under this code, prescriptive and performance approaches for compliance are permitted, resulting in the demand for alternative methods of enforcement: technical assistance, plan review, field inspection, and computer analysis. In contrast to existing to construction, building design and new materials and construction practices are of critical importance in new construction, creating a need for extensive technical assistance and extensive interaction between enforcement personnel and the building community. Compliance problems associated with building design and installation did occur in both residential and nonresidential buildings. 12 refs., 5 tabs.« less
Angeler, David G; Viedma, Olga; Moreno, José M
2009-11-01
Time lag analysis (TLA) is a distance-based approach used to study temporal dynamics of ecological communities by measuring community dissimilarity over increasing time lags. Despite its increased use in recent years, its performance in comparison with other more direct methods (i.e., canonical ordination) has not been evaluated. This study fills this gap using extensive simulations and real data sets from experimental temporary ponds (true zooplankton communities) and landscape studies (landscape categories as pseudo-communities) that differ in community structure and anthropogenic stress history. Modeling time with a principal coordinate of neighborhood matrices (PCNM) approach, the canonical ordination technique (redundancy analysis; RDA) consistently outperformed the other statistical tests (i.e., TLAs, Mantel test, and RDA based on linear time trends) using all real data. In addition, the RDA-PCNM revealed different patterns of temporal change, and the strength of each individual time pattern, in terms of adjusted variance explained, could be evaluated, It also identified species contributions to these patterns of temporal change. This additional information is not provided by distance-based methods. The simulation study revealed better Type I error properties of the canonical ordination techniques compared with the distance-based approaches when no deterministic component of change was imposed on the communities. The simulation also revealed that strong emphasis on uniform deterministic change and low variability at other temporal scales is needed to result in decreased statistical power of the RDA-PCNM approach relative to the other methods. Based on the statistical performance of and information content provided by RDA-PCNM models, this technique serves ecologists as a powerful tool for modeling temporal change of ecological (pseudo-) communities.
Protein normal-mode dynamics: trypsin inhibitor, crambin, ribonuclease and lysozyme.
Levitt, M; Sander, C; Stern, P S
1985-02-05
We have developed a new method for modelling protein dynamics using normal-mode analysis in internal co-ordinates. This method, normal-mode dynamics, is particularly well suited for modelling collective motion, makes possible direct visualization of biologically interesting modes, and is complementary to the more time-consuming simulation of molecular dynamics trajectories. The essential assumption and limitation of normal-mode analysis is that the molecular potential energy varies quadratically. Our study starts with energy minimization of the X-ray co-ordinates with respect to the single-bond torsion angles. The main technical task is the calculation of second derivative matrices of kinetic and potential energy with respect to the torsion angle co-ordinates. These enter into a generalized eigenvalue problem, and the final eigenvalues and eigenvectors provide a complete description of the motion in the basic 0.1 to 10 picosecond range. Thermodynamic averages of amplitudes, fluctuations and correlations can be calculated efficiently using analytical formulae. The general method presented here is applied to four proteins, trypsin inhibitor, crambin, ribonuclease and lysozyme. When the resulting atomic motion is visualized by computer graphics, it is clear that the motion of each protein is collective with all atoms participating in each mode. The slow modes, with frequencies of below 10 cm-1 (a period of 3 ps), are the most interesting in that the motion in these modes is segmental. The root-mean-square atomic fluctuations, which are dominated by a few slow modes, agree well with experimental temperature factors (B values). The normal-mode dynamics of these four proteins have many features in common, although in the larger molecules, lysozyme and ribonuclease, there is low frequency domain motion about the active site.
McEvoy, Phil; Escott, Diane; Bee, Penny
2011-01-01
This study is based on a formative evaluation of a case management service for high-intensity service users in Northern England. The evaluation had three main purposes: (i) to assess the quality of the organisational infrastructure; (ii) to obtain a better understanding of the key influences that played a role in shaping the development of the service; and (iii) to identify potential changes in practice that may help to improve the quality of service provision. The evaluation was informed by Gittell's relational co-ordination theory, which focuses upon cross-boundary working practices that facilitate task integration. The Assessment of Chronic Illness Care Survey was used to assess the organisational infrastructure and qualitative interviews with front line staff were conducted to explore the key influences that shaped the development of the service. A high level of strategic commitment and political support for integrated working was identified. However, the quality of care co-ordination was variable. The most prominent operational factor that appeared to influence the scope and quality of care co-ordination was the pattern of interaction between the case managers and their co-workers. The co-ordination of patient care was much more effective in integrated co-ordination networks. Key features included clearly defined, task focussed, relational workspaces with interactive forums where case managers could engage with co-workers in discussions about the management of interdependent care activities. In dispersed co-ordination networks with fewer relational workspaces, the case managers struggled to work as effectively. The evaluation concluded that the creation of flexible and efficient task focused relational workspaces that are systemically managed and adequately resourced could help to improve the quality of care co-ordination, particularly in dispersed networks. © 2010 Blackwell Publishing Ltd.
Projected health impact of the Los Angeles City living wage ordinance
Cole, B.; Shimkhada, R.; Morgenstern, H.; Kominski, G.; Fielding, J.; Wu, S.
2005-01-01
Study objective: To estimate the relative health effects of the income and health insurance provisions of the Los Angeles City living wage ordinance. Setting and participants: About 10 000 employees of city contractors are subject to the Los Angeles City living wage ordinance, which establishes an annually adjusted minimum wage ($7.99 per hour in July 2002) and requires employers to contribute $1.25 per hour worked towards employees' health insurance, or, if health insurance is not provided, to add this amount to wages. Design: As part of a comprehensive health impact assessment (HIA), we used estimates of the effects of health insurance and income on mortality from the published literature to construct a model to estimate and compare potential reductions in mortality attributable to the increases in wage and changes in health insurance status among workers covered by the Los Angeles City living wage ordinance. Results: The model predicts that the ordinance currently reduces mortality by 1.4 deaths per year per 10 000 workers at a cost of $27.5 million per death prevented. If the ordinance were modified so that all uninsured workers received health insurance, mortality would be reduced by eight deaths per year per 10 000 workers at a cost of $3.4 million per death prevented. Conclusions: The health insurance provisions of the ordinance have the potential to benefit the health of covered workers far more cost effectively than the wage provisions of the ordinance. This analytical model can be adapted and used in other health impact assessments of related policy actions that might affect either income or access to health insurance in the affected population. PMID:16020640
Projected health impact of the Los Angeles City living wage ordinance.
Cole, Brian L; Shimkhada, Riti; Morgenstern, Hal; Kominski, Gerald; Fielding, Jonathan E; Wu, Sheng
2005-08-01
To estimate the relative health effects of the income and health insurance provisions of the Los Angeles City living wage ordinance. About 10 000 employees of city contractors are subject to the Los Angeles City living wage ordinance, which establishes an annually adjusted minimum wage (7.99 US dollars per hour in July 2002) and requires employers to contribute 1.25 US dollars per hour worked towards employees' health insurance, or, if health insurance is not provided, to add this amount to wages. As part of a comprehensive health impact assessment (HIA), we used estimates of the effects of health insurance and income on mortality from the published literature to construct a model to estimate and compare potential reductions in mortality attributable to the increases in wage and changes in health insurance status among workers covered by the Los Angeles City living wage ordinance. The model predicts that the ordinance currently reduces mortality by 1.4 deaths per year per 10,000 workers at a cost of 27.5 million US dollars per death prevented. If the ordinance were modified so that all uninsured workers received health insurance, mortality would be reduced by eight deaths per year per 10,000 workers at a cost of 3.4 million US dollars per death prevented. The health insurance provisions of the ordinance have the potential to benefit the health of covered workers far more cost effectively than the wage provisions of the ordinance. This analytical model can be adapted and used in other health impact assessments of related policy actions that might affect either income or access to health insurance in the affected population.
Tree species and size structure of old-growth Douglas-fir forests in central western Oregon, USA
Poage, Nathan; Tappeiner, J. C.
2005-01-01
We characterized the structure of 91 old-growth forests dominated by Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), using inventory data from recent (1985a??1991) old-growth timber sales in western Oregon. The data were complete counts (i.e., censuses) of all live trees >20 cm diameter at breast height (dbh, measured at 1.4 m above the ground) over a mean area of 17.1 ha at each site. Across all sites, Douglas-fir accounted for 79% of the total basal area (m2/ha) of all species. The average density of trees >100 cm dbh was 19 trees/ha and 90% of these trees were Douglas-fir. Species other than Douglas-fir constituted only about 20% of the total basal area at each old-growth site, on average, but largely accounted for the structural variation between sites. We used multivariate techniques such as cluster analysis, indicator species analysis, and ordination with non-metric multidimensional scaling (NMS) to identify and characterize six structural groups in terms of basal area in different speciesa??diameter classes. Almost 97% of the structural information was captured by the first (r2 = 0.841) and second (r2 = 0.128) NMS ordination axis. Geographic information systems (GIS) analysis and NMS indicated that the structural differences among groups of sites were associated with moisture, temperature, and elevation gradients within the study area. This type of analysis can be used to help define differences among old-growth forests and to set local structural goals for growing forests with old-growth characteristics.
Sick leave and its determinants in professional soldiers of the Slovenian Armed Forces.
Selič, Polona; Petek, Davorina; Serec, Maša; Rus Makovec, Maja
2010-12-01
To assess whether demographic characteristics, self-rated health status, coping behaviors, satisfaction with important interpersonal relationships, financial situation, and current overall quality of life are determinants of sick leave duration in professional soldiers of the Slovenian Armed Forces. In 2008, 448 military personnel on active duty in the Slovenian Armed Forces were invited to participate in the study and 390 returned the completed questionnaires (response rate 87%). The questionnaires used were the self-rated health scale, sick leave scale, life satisfaction scale, Folkman-Lazarus' Ways of Coping Questionnaire, and a demographic data questionnaire. To partition the variance across a wide variety of indicators of participants' experiences, ordinal modeling procedures were used. A multivariate ordinal regression model, explaining 24% of sick leave variance, showed that the following variables significantly predicted longer sick leave duration: female sex (estimate, 1.185; 95% confidence interval [CI], 0.579-1.791), poorer self-rated health (estimate, 3.243; 95% CI, 1.755-4.731), lower satisfaction with relationships with coworkers (estimate, 1.333; 95% CI, 0.399-2.267), and lower education (estimate, 1.577; 95% CI, 0.717-2.436). The impact of age and coping mechanisms was not significant. Longer sick leave duration was found in women and respondents less satisfied with their relationships with coworkers, and these are the groups to which special attention should be awarded when planning supervision, work procedures, and gender equality policy of the Armed Forces. A good way of increasing the quality of interpersonal relationships at work would be to teach such skills in teaching programs for commanding officers.
Matsushima, Kazuhide; Peng, Monica; Velasco, Carlos; Schaefer, Eric; Diaz-Arrastia, Ramon; Frankel, Heidi
2012-04-01
Significant glycemic excursions (so-called glucose variability) affect the outcome of generic critically ill patients but has not been well studied in patients with traumatic brain injury (TBI). The purpose of this study was to evaluate the impact of glucose variability on long-term functional outcome of patients with TBI. A noncomputerized tight glucose control protocol was used in our intensivist model surgical intensive care unit. The relationship between the glucose variability and long-term (a median of 6 months after injury) functional outcome defined by extended Glasgow Outcome Scale (GOSE) was analyzed using ordinal logistic regression models. Glucose variability was defined by SD and percentage of excursion (POE) from the preset range glucose level. A total of 109 patients with TBI under tight glucose control had long-term GOSE evaluated. In univariable analysis, there was a significant association between lower GOSE score and higher mean glucose, higher SD, POE more than 60, POE 80 to 150, and single episode of glucose less than 60 mg/dL but not POE 80 to 110. After adjusting for possible confounding variables in multivariable ordinal logistic regression models, higher SD, POE more than 60, POE 80 to 150, and single episode of glucose less than 60 mg/dL were significantly associated with lower GOSE score. Glucose variability was significantly associated with poorer long-term functional outcome in patients with TBI as measured by the GOSE score. Well-designed protocols to minimize glucose variability may be key in improving long-term functional outcome. Copyright © 2012 Elsevier Inc. All rights reserved.
Overview of Existing Wind Energy Ordinances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oteri, F.
2008-12-01
Due to increased energy demand in the United States, rural communities with limited or no experience with wind energy now have the opportunity to become involved in this industry. Communities with good wind resources may be approached by entities with plans to develop the resource. Although these opportunities can create new revenue in the form of construction jobs and land lease payments, they also create a new responsibility on the part of local governments to ensure that ordinances will be established to aid the development of safe facilities that will be embraced by the community. The purpose of this reportmore » is to educate and engage state and local governments, as well as policymakers, about existing large wind energy ordinances. These groups will have a collection of examples to utilize when they attempt to draft a new large wind energy ordinance in a town or county without existing ordinances.« less
Detect and exploit hidden structure in fatty acid signature data
Budge, Suzanne; Bromaghin, Jeffrey F.; Thiemann, Gregory
2017-01-01
Estimates of predator diet composition are essential to our understanding of their ecology. Although several methods of estimating diet are practiced, methods based on biomarkers have become increasingly common. Quantitative fatty acid signature analysis (QFASA) is a popular method that continues to be refined and extended. Quantitative fatty acid signature analysis is based on differences in the signatures of prey types, often species, which are recognized and designated by investigators. Similarly, predator signatures may be structured by known factors such as sex or age class, and the season or region of sample collection. The recognized structure in signature data inherently influences QFASA results in important and typically beneficial ways. However, predator and prey signatures may contain additional, hidden structure that investigators either choose not to incorporate into an analysis or of which they are unaware, being caused by unknown ecological mechanisms. Hidden structure also influences QFASA results, most often negatively. We developed a new method to explore signature data for hidden structure, called divisive magnetic clustering (DIMAC). Our DIMAC approach is based on the same distance measure used in diet estimation, closely linking methods of data exploration and parameter estimation, and it does not require data transformation or distributional assumptions, as do many multivariate ordination methods in common use. We investigated the potential benefits of the DIMAC method to detect and subsequently exploit hidden structure in signature data using two prey signature libraries with quite different characteristics. We found that the existence of hidden structure in prey signatures can increase the confusion between prey types and thereby reduce the accuracy and precision of QFASA diet estimates. Conversely, the detection and exploitation of hidden structure represent a potential opportunity to improve predator diet estimates and may lead to new insights into the ecology of either predator or prey. The DIMAC algorithm is implemented in the R diet estimation package qfasar.
Quasi-heterogeneous efficient 3-D discrete ordinates CANDU calculations using Attila
DOE Office of Scientific and Technical Information (OSTI.GOV)
Preeti, T.; Rulko, R.
2012-07-01
In this paper, 3-D quasi-heterogeneous large scale parallel Attila calculations of a generic CANDU test problem consisting of 42 complete fuel channels and a perpendicular to fuel reactivity device are presented. The solution method is that of discrete ordinates SN and the computational model is quasi-heterogeneous, i.e. fuel bundle is partially homogenized into five homogeneous rings consistently with the DRAGON code model used by the industry for the incremental cross-section generation. In calculations, the HELIOS-generated 45 macroscopic cross-sections library was used. This approach to CANDU calculations has the following advantages: 1) it allows detailed bundle (and eventually channel) power calculationsmore » for each fuel ring in a bundle, 2) it allows the exact reactivity device representation for its precise reactivity worth calculation, and 3) it eliminates the need for incremental cross-sections. Our results are compared to the reference Monte Carlo MCNP solution. In addition, the Attila SN method performance in CANDU calculations characterized by significant up scattering is discussed. (authors)« less
Jafari, Peyman; Sharafi, Zahra; Bagheri, Zahra; Shalileh, Sara
2014-06-01
Measurement equivalence is a necessary assumption for meaningful comparison of pediatric quality of life rated by children and parents. In this study, differential item functioning (DIF) analysis is used to examine whether children and their parents respond consistently to the items in the KINDer Lebensqualitätsfragebogen (KINDL; in German, Children Quality of Life Questionnaire). Two DIF detection methods, graded response model (GRM) and ordinal logistic regression (OLR), were applied for comparability. The KINDL was completed by 1,086 school children and 1,061 of their parents. While the GRM revealed that 12 out of the 24 items were flagged with DIF, the OLR identified 14 out of the 24 items with DIF. Seven items with DIF and five items without DIF were common across the two methods, yielding a total agreement rate of 50 %. This study revealed that parent proxy-reports cannot be used as a substitute for a child's ratings in the KINDL.
Young Children's Ability to Use Ordinal Labels in a Spatial Search Task
ERIC Educational Resources Information Center
Miller, Stephanie E.; Marcovitch, Stuart; Boseovski, Janet J.; Lewkowicz, David J.
2015-01-01
The use and understanding of ordinal terms (e.g., "first" and "second") is a developmental milestone that has been relatively unexplored in the preschool age range. In the present study, 4- and 5-year-olds watched as a reward was placed in one of three train cars labeled by the experimenter with an ordinal (e.g.,…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-13
... land. The tribal land is located on trust land and this Ordinance allows for the possession and sale of alcoholic beverages. This Ordinance will increase the ability of the tribal government to control the distribution and possession of liquor within their tribal land, and at the same time will provide an important...
Yuan, Ke-Hai; Jiang, Ge; Cheng, Ying
2017-11-01
Data in psychology are often collected using Likert-type scales, and it has been shown that factor analysis of Likert-type data is better performed on the polychoric correlation matrix than on the product-moment covariance matrix, especially when the distributions of the observed variables are skewed. In theory, factor analysis of the polychoric correlation matrix is best conducted using generalized least squares with an asymptotically correct weight matrix (AGLS). However, simulation studies showed that both least squares (LS) and diagonally weighted least squares (DWLS) perform better than AGLS, and thus LS or DWLS is routinely used in practice. In either LS or DWLS, the associations among the polychoric correlation coefficients are completely ignored. To mend such a gap between statistical theory and empirical work, this paper proposes new methods, called ridge GLS, for factor analysis of ordinal data. Monte Carlo results show that, for a wide range of sample sizes, ridge GLS methods yield uniformly more accurate parameter estimates than existing methods (LS, DWLS, AGLS). A real-data example indicates that estimates by ridge GLS are 9-20% more efficient than those by existing methods. Rescaled and adjusted test statistics as well as sandwich-type standard errors following the ridge GLS methods also perform reasonably well. © 2017 The British Psychological Society.
High-order solution methods for grey discrete ordinates thermal radiative transfer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maginot, Peter G., E-mail: maginot1@llnl.gov; Ragusa, Jean C., E-mail: jean.ragusa@tamu.edu; Morel, Jim E., E-mail: morel@tamu.edu
This work presents a solution methodology for solving the grey radiative transfer equations that is both spatially and temporally more accurate than the canonical radiative transfer solution technique of linear discontinuous finite element discretization in space with implicit Euler integration in time. We solve the grey radiative transfer equations by fully converging the nonlinear temperature dependence of the material specific heat, material opacities, and Planck function. The grey radiative transfer equations are discretized in space using arbitrary-order self-lumping discontinuous finite elements and integrated in time with arbitrary-order diagonally implicit Runge–Kutta time integration techniques. Iterative convergence of the radiation equation ismore » accelerated using a modified interior penalty diffusion operator to precondition the full discrete ordinates transport operator.« less
High-order solution methods for grey discrete ordinates thermal radiative transfer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maginot, Peter G.; Ragusa, Jean C.; Morel, Jim E.
This paper presents a solution methodology for solving the grey radiative transfer equations that is both spatially and temporally more accurate than the canonical radiative transfer solution technique of linear discontinuous finite element discretization in space with implicit Euler integration in time. We solve the grey radiative transfer equations by fully converging the nonlinear temperature dependence of the material specific heat, material opacities, and Planck function. The grey radiative transfer equations are discretized in space using arbitrary-order self-lumping discontinuous finite elements and integrated in time with arbitrary-order diagonally implicit Runge–Kutta time integration techniques. Iterative convergence of the radiation equation ismore » accelerated using a modified interior penalty diffusion operator to precondition the full discrete ordinates transport operator.« less
High-order solution methods for grey discrete ordinates thermal radiative transfer
Maginot, Peter G.; Ragusa, Jean C.; Morel, Jim E.
2016-09-29
This paper presents a solution methodology for solving the grey radiative transfer equations that is both spatially and temporally more accurate than the canonical radiative transfer solution technique of linear discontinuous finite element discretization in space with implicit Euler integration in time. We solve the grey radiative transfer equations by fully converging the nonlinear temperature dependence of the material specific heat, material opacities, and Planck function. The grey radiative transfer equations are discretized in space using arbitrary-order self-lumping discontinuous finite elements and integrated in time with arbitrary-order diagonally implicit Runge–Kutta time integration techniques. Iterative convergence of the radiation equation ismore » accelerated using a modified interior penalty diffusion operator to precondition the full discrete ordinates transport operator.« less
Ezeamama, Amara E; Viali, Satupaitea; Tuitele, John; McGarvey, Stephen T
2006-11-01
Early in economic development there are positive associations between socioeconomic status (SES) and cardiovascular disease (CVD) risk factors, and in the most developed market economy societies there are negative associations. The purpose of this report is to describe cross-sectional and longitudinal associations between indicators of SES and CVD risk factors in a genetically homogenous population of Samoans at different levels of economic development. At baseline 1289 participants 25-58yrs, and at 4-year follow-up, 963 participants were studied in less economically developed Samoa and in more developed American Samoa. SES was assessed by education, occupation, and material lifestyle at baseline. The CVD risk factors, obesity, type-2 diabetes and hypertension were measured at baseline and 4-year follow-up, and an index of any incident CVD risk factor at follow-up was calculated. Sex and location (Samoa and American Samoa) specific multivariable logistic regression models were used to test for relationships between SES and CVD risk factors at baseline after adjustment for age and the other SES indicators. In addition an ordinal SES index was constructed for each individual based on all three SES indicators, and used in a multivariable model to estimate the predicted probability of CVD risk factors across the SES index for the two locations. In both the models using specific SES measures and CVD risk factor outcomes, and the models using the ordinal SES index and predicted probabilities of CVD risk factors, we detected a pattern of high SES associated with: (1) elevated odds of CVD risk factors in less developed Samoa, and (2) decreased odds of CVD risk factors in more developed American Samoa. We conclude that the pattern of inverse associations between SES and CVD risk factors in Samoa and direct associations in American Samoa is attributable to the heterogeneity across the Samoas in specific exposures to social processes of economic development and the natural history of individual CVD risk factors. The findings suggest that interventions on non-communicable diseases in the Samoas must be devised based on the level of economic development, the socio-economic context of risk factor exposures, and individual characteristics such as age, sex and education level.
Sacramento's parking lot shading ordinance: environmental and economic costs of compliance
E.G. McPherson
2001-01-01
A survey of 15 Sacramento parking lots and computer modeling were used to evaluate parking capacity and compliance with the 1983 ordinance requiring 50% shade of paved areas (PA) 15 years after development. There were 6% more parking spaces than required by ordinance, and 36% were vacant during peak use periods. Current shade was 14% with 44% of this amount provided by...
Code of Federal Regulations, 2011 CFR
2011-01-01
... government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities... REGULATION REAL PROPERTY 74-FACILITY MANAGEMENT Facility Management Smoking § 102-74.351 If a state or local government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities...
Code of Federal Regulations, 2014 CFR
2014-01-01
... government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities... REGULATION REAL PROPERTY 74-FACILITY MANAGEMENT Facility Management Smoking § 102-74.351 If a state or local government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities...
Code of Federal Regulations, 2010 CFR
2010-07-01
... government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities... REGULATION REAL PROPERTY 74-FACILITY MANAGEMENT Facility Management Smoking § 102-74.351 If a state or local government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities...
Code of Federal Regulations, 2013 CFR
2013-07-01
... government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities... REGULATION REAL PROPERTY 74-FACILITY MANAGEMENT Facility Management Smoking § 102-74.351 If a state or local government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities...
Code of Federal Regulations, 2012 CFR
2012-01-01
... government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities... REGULATION REAL PROPERTY 74-FACILITY MANAGEMENT Facility Management Smoking § 102-74.351 If a state or local government has a smoke-free ordinance that is more strict than the smoking policy for Federal facilities...
Sprauten, Mette; Darrah, Thomas H.; Peterson, Derick R.; Campbell, M. Ellen; Hannigan, Robyn E.; Cvancarova, Milada; Beard, Clair; Haugnes, Hege S.; Fosså, Sophie D.; Oldenburg, Jan; Travis, Lois B.
2012-01-01
Purpose Cisplatin-induced neurotoxicity and ototoxicity (NTX) are important adverse effects after chemotherapy for testicular cancer (TC). Although serum platinum is measurable years after therapy, its impact on NTX has not been evaluated. Patients and Methods In all, 169 cisplatin-treated survivors of TC provided blood samples at Survey I and reported NTX during Survey I (1998-2002) and Survey II (2007-2008). Serum platinum was quantified by inductively coupled plasma mass spectrometry. Patient-reported outcomes were evaluated with the Scale for Chemotherapy-Induced Neurotoxicity (SCIN), regarding the extent of symptom bother as 0, “not at all”; 1, “a little”; 2, “quite a bit”; or 3, “very much.” Summing the six symptom scores yielded a total SCIN score of 0 to 18. Categorizing total SCIN scores into quartiles yielded similar-sized groups with increasing symptoms. Multivariate ordinal logistic regression analyses evaluated associations between NTX and long-term serum platinum levels, adjusting for cisplatin dose, dosing schedule, and age. Results At Survey I, a significant four- to five-fold association with total SCIN score emerged for the highest serum platinum quartile (odds ratio [OR], 4.69; 95% CI, 1.82 to 12.08). Paresthesias and Raynaud's syndrome (hands and feet) showed significant two- to four-fold increased risks with the highest platinum quartile. At Survey II, total SCIN score remained significantly associated with the highest platinum quartile (OR, 4.28; 95% CI, 1.36 to 13.48). Paresthesias (hands and feet) and tinnitus showed significant three- to four-fold increased risks for the highest platinum quartile. Cumulative cisplatin dose was not associated with total SCIN score or individual SCIN symptoms in multivariate analyses. Conclusion Here we document a significant relationship between increasing levels of residual serum platinum and NTX severity after adjusting for initial cisplatin dose. PMID:22184390
2012-01-01
Background Knowledge of tuberculosis has been shown to influence health seeking behaviour; and urban slum dwellers are at a higher risk of acquiring tuberculosis than the general population. The study aim was to assess knowledge of tuberculosis and identify the associated socio-demographic determinants, in order to inform tailored interventions for advocacy, communication and social mobilisation in three urban-slum communities of Uganda. Methods A cross-sectional survey of 1361 adults between April and October 2011. Data was analyzed by descriptive statistics. Adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) of potential determinants of tuberculosis (TB) knowledge were estimated by multivariable ordinal logistic regression using Stata 11.2 software. Results We found low knowledge of TB cause (26.7%); symptoms (46.8%), transmission (54.3%), prevention (34%) and free treatment (35%). Knowledge about TB treatment (69.4) and cure (85.1) was relatively high. Independent determinants of poor knowledge of TB in the multivariable analysis included (aOR, 95% CI) lack of formal education (0.56; 0.38 – 0.83, P = 0.004), unemployment (0.67; 0.49 – 0.90, P = 0.010) and never testing for HIV (0.69; 0.51 – 0.92, P < 0.012). Whilst, older age (1.73; 1.30 – 2.29, P < 0.001) and residing in Lira (2.02; 1.50 – 2.72, P < 0.001) were independent determinants of higher knowledge of TB. Conclusion This study revealed deficiencies in the public health knowledge about TB symptoms, diagnosis and treatment among urban-slum dwellers in Uganda. Tuberculosis control programmes in similar settings should consider innovative strategies for TB education, advocacy, communication and social mobilisation to reach the youth, unemployed and less-educated; as well as those who have never tested for HIV. PMID:22824498
Gijsberts, Crystel M.; Seneviratna, Aruni; de Carvalho, Leonardo P.; den Ruijter, Hester M.; Vidanapthirana, Puwalani; Sorokin, Vitaly; Stella, Pieter; Agostoni, Pierfrancesco; Asselbergs, Folkert W.; Richards, A. Mark; Low, Adrian F.; Lee, Chi-Hang; Tan, Huay Cheem; Hoefer, Imo E.; Pasterkamp, Gerard; de Kleijn, Dominique P. V.; Chan, Mark Y.
2015-01-01
Background In 2020 the largest number of patients with coronary artery disease (CAD) will be found in Asia. Published epidemiological and clinical reports are overwhelmingly derived from western (White) cohorts and data from Asia are scant. We compared CAD severity and all-cause mortality among 4 of the world’s most populous ethnicities: Whites, Chinese, Indians and Malays. Methods The UNIted CORoNary cohort (UNICORN) simultaneously enrolled parallel populations of consecutive patients undergoing coronary angiography or intervention for suspected CAD in the Netherlands and Singapore. Using multivariable ordinal regression, we investigated the independent association of ethnicity with CAD severity and interactions between risk factors and ethnicity on CAD severity. Also, we compared all-cause mortality among the ethnic groups using multivariable Cox regression analysis. Results We included 1,759 White, 685 Chinese, 201 Indian and 224 Malay patients undergoing coronary angiography. We found distinct inter-ethnic differences in cardiovascular risk factors. Furthermore, the associations of gender and diabetes with severity of CAD were significantly stronger in Chinese than Whites. Chinese (OR 1.3 [1.1–1.7], p = 0.008) and Malay (OR 1.9 [1.4–2.6], p<0.001) ethnicity were independently associated with more severe CAD as compared to White ethnicity. Strikingly, when stratified for diabetes status, we found a significant association of all three Asian ethnic groups as compared to White ethnicity with more severe CAD among diabetics, but not in non-diabetics. Crude all-cause mortality did not differ, but when adjusted for covariates mortality was higher in Malays than the other ethnic groups. Conclusion In this population of individuals undergoing coronary angiography, ethnicity is independently associated with the severity of CAD and modifies the strength of association between certain risk factors and CAD severity. Furthermore, mortality differs among ethnic groups. Our data provide insight in inter-ethnic differences in CAD risk factors, CAD severity and mortality. PMID:26147693
Vegetation characteristics important to common songbirds in east Texas
Conner, Richard N.; Dickson, James G.; Locke, Brian A.; Segelquist, Charles A.
1983-01-01
Multivariate studies of breeding bird communities have used principal component analysis (PCA) or several-group (three or more groups) discriminant function analysis (DFA) to ordinate bird species on vegetational continua (Cody 1968, James 1971, Whitmore 1975). In community studies, high resolution of habitat requirements for individual species is not always possible with either PCA or several-group DFA. When habitat characteristics of several species are examined with a DFA the resultant axes optimally discriminate among all species simultaneously. Hence, the characteristics assigned to a particular species reflect in part the presence of other species in the analyses. A better resolution of each species' habitat requirements may be obtained from a two-group DFA, wherein habitats selected by a species are discriminated from all other available habitats. Analyses using two-group DFAs to compare habitat used by a species with habitat unused by the same species have the potential to provide an optimal frame of reference from which to examine habitat variables (Martinka 1972, Conner and Adkisson 1976, Whitmore 1981). Mathematically (DFA) it is possible to maximally separate two groups of multivariate observations with a single axis (Harner and whitmore 1977). A line drawn in three or n-dimensional space can easily be positioned to intersect two multivariate means (centroids). If three or more centroids for species are analyzed simultaneously, a single line can no longer intersect all centroids unless a perfectly linear relationship exists for the species being examined. The probability of such an occurrence is extremely low. Thus, a high degree of resolution can be realized when a two-group DFA is used to determine habitat parameters important to individual species. We have used two-group DFA to identify vegetation variable important to 12 common species of songbirds in East Texas.
Chang, Susan M; Barker, Fred G
2005-11-01
Social factors influence cancer treatment choices, potentially affecting patient survival. In the current study, the authors studied the interrelations between marital status, treatment received, and survival in patients with glioblastoma multiforme (GM), using population-based data. The data source was the Surveillance, Epidemiology, and End Results (SEER) Public Use Database, 1988-2001, 2004 release, all registries. Multivariate logistic, ordinal, and Cox regression analyses adjusted for demographic and clinical variables were used. Of 10,987 patients with GM, 67% were married, 31% were unmarried, and 2% were of unknown marital status. Tumors were slightly larger at the time of diagnosis in unmarried patients (49% of unmarried patients had tumors larger than 45 mm vs. 45% of married patients; P = 0.004, multivariate analysis). Unmarried patients were less likely to undergo surgical resection (vs. biopsy; 75% of unmarried patients vs. 78% of married patients) and were less likely to receive postoperative radiation therapy (RT) (70% of unmarried patients vs. 79% of married patients). On multivariate analysis, the odds ratio (OR) for resection (vs. biopsy) in unmarried patients was 0.88 (95% confidence interval [95% CI], 0.79-0.98; P = 0.02), and the OR for RT in unmarried patients was 0.69 (95% CI, 0.62-0.77; P < 0.001). Unmarried patients more often refused both surgical resection and RT. Unmarried patients who underwent surgical resection and RT were found to have a shorter survival than similarly treated married patients (hazard ratio for unmarried patients, 1.10; P = 0.003). Unmarried patients with GM presented with larger tumors, were less likely to undergo both surgical resection and postoperative RT, and had a shorter survival after diagnosis when compared with married patients, even after adjustment for treatment and other prognostic factors. (c) 2005 American Cancer Society.
Liu, Yong; Su, Chao; Zhang, Hong; Li, Xiaoting; Pei, Jingfei
2014-01-01
Many studies indicated that industrialization and urbanization caused serious soil heavy metal pollution from industrialized age. However, fewer previous studies have conducted a combined analysis of the landscape pattern, urbanization, industrialization, and heavy metal pollution. This paper was aimed at exploring the relationships of heavy metals in the soil (Pb, Cu, Ni, As, Cd, Cr, Hg, and Zn) with landscape pattern, industrialisation, urbanisation in Taiyuan city using multivariate analysis. The multivariate analysis included correlation analysis, analysis of variance (ANOVA), independent-sample T test, and principal component analysis (PCA). Geographic information system (GIS) was also applied to determine the spatial distribution of the heavy metals. The spatial distribution maps showed that the heavy metal pollution of the soil was more serious in the centre of the study area. The results of the multivariate analysis indicated that the correlations among heavy metals were significant, and industrialisation could significantly affect the concentrations of some heavy metals. Landscape diversity showed a significant negative correlation with the heavy metal concentrations. The PCA showed that a two-factor model for heavy metal pollution, industrialisation, and the landscape pattern could effectively demonstrate the relationships between these variables. The model explained 86.71% of the total variance of the data. Moreover, the first factor was mainly loaded with the comprehensive pollution index (P), and the second factor was primarily loaded with landscape diversity and dominance (H and D). An ordination of 80 samples could show the pollution pattern of all the samples. The results revealed that local industrialisation caused heavy metal pollution of the soil, but such pollution could respond negatively to the landscape pattern. The results of the study could provide a basis for agricultural, suburban, and urban planning. PMID:25251460
Liu, Yong; Su, Chao; Zhang, Hong; Li, Xiaoting; Pei, Jingfei
2014-01-01
Many studies indicated that industrialization and urbanization caused serious soil heavy metal pollution from industrialized age. However, fewer previous studies have conducted a combined analysis of the landscape pattern, urbanization, industrialization, and heavy metal pollution. This paper was aimed at exploring the relationships of heavy metals in the soil (Pb, Cu, Ni, As, Cd, Cr, Hg, and Zn) with landscape pattern, industrialisation, urbanisation in Taiyuan city using multivariate analysis. The multivariate analysis included correlation analysis, analysis of variance (ANOVA), independent-sample T test, and principal component analysis (PCA). Geographic information system (GIS) was also applied to determine the spatial distribution of the heavy metals. The spatial distribution maps showed that the heavy metal pollution of the soil was more serious in the centre of the study area. The results of the multivariate analysis indicated that the correlations among heavy metals were significant, and industrialisation could significantly affect the concentrations of some heavy metals. Landscape diversity showed a significant negative correlation with the heavy metal concentrations. The PCA showed that a two-factor model for heavy metal pollution, industrialisation, and the landscape pattern could effectively demonstrate the relationships between these variables. The model explained 86.71% of the total variance of the data. Moreover, the first factor was mainly loaded with the comprehensive pollution index (P), and the second factor was primarily loaded with landscape diversity and dominance (H and D). An ordination of 80 samples could show the pollution pattern of all the samples. The results revealed that local industrialisation caused heavy metal pollution of the soil, but such pollution could respond negatively to the landscape pattern. The results of the study could provide a basis for agricultural, suburban, and urban planning.
Biernacki, Marcin; Tarnowski, Adam
2008-01-01
When assessing the psychological suitability for the profession of a pilot, it is important to consider personality traits and psychomotor abilities. Our study aimed at estimating the role of temperamental traits as components of pilots' personality in eye-hand co-ordination. The assumption was that differences in the escalation of the level of temperamental traits, as measured with the Formal Characteristic of Behaviour-Temperament Inventory (FCB-TI), will significantly influence eye-hand co-ordination. At the level of general scores, enhanced briskness proved to be the most important trait for eye-hand co-ordination. An analysis of partial scores additionally underlined the importance of sensory sensitivity, endurance and activity. The application of eye-hand co-ordination tasks, which involve energetic and temporal dimensions of performance, helped to disclose the role of biologically-based personality traits in psychomotor performance. The implication of these findings for selecting pilots is discussed.
Genomic-Enabled Prediction of Ordinal Data with Bayesian Logistic Ordinal Regression.
Montesinos-López, Osval A; Montesinos-López, Abelardo; Crossa, José; Burgueño, Juan; Eskridge, Kent
2015-08-18
Most genomic-enabled prediction models developed so far assume that the response variable is continuous and normally distributed. The exception is the probit model, developed for ordered categorical phenotypes. In statistical applications, because of the easy implementation of the Bayesian probit ordinal regression (BPOR) model, Bayesian logistic ordinal regression (BLOR) is implemented rarely in the context of genomic-enabled prediction [sample size (n) is much smaller than the number of parameters (p)]. For this reason, in this paper we propose a BLOR model using the Pólya-Gamma data augmentation approach that produces a Gibbs sampler with similar full conditional distributions of the BPOR model and with the advantage that the BPOR model is a particular case of the BLOR model. We evaluated the proposed model by using simulation and two real data sets. Results indicate that our BLOR model is a good alternative for analyzing ordinal data in the context of genomic-enabled prediction with the probit or logit link. Copyright © 2015 Montesinos-López et al.
ERIC Educational Resources Information Center
Moustaki, Irini; Joreskog, Karl G.; Mavridis, Dimitris
2004-01-01
We consider a general type of model for analyzing ordinal variables with covariate effects and 2 approaches for analyzing data for such models, the item response theory (IRT) approach and the PRELIS-LISREL (PLA) approach. We compare these 2 approaches on the basis of 2 examples, 1 involving only covariate effects directly on the ordinal variables…
Legislations combating counterfeit drugs in Hong Kong.
Lai, C W; Chan, W K
2013-08-01
To understand legislation combating counterfeit drugs in Hong Kong. This study consisted of two parts. In part I, counterfeit drugs–related ordinances and court cases were reviewed. In part II, indepth interviews of the stakeholders were described. Hong Kong. All Hong Kong ordinances were screened manually to identify those combating counterfeit drugs. Court cases were searched for each of the identified cases. Then, the relevant judgement justifications were analysed to identify sentencing issues. Indepth interviews with the stakeholders were conducted to understand their perceptions about such legislation. Trade Marks Ordinance, Patents Ordinance, Trade Descriptions Ordinance, and Pharmacy and Poisons Ordinance were current legislative items combating counterfeit drugs. Sentencing criteria depended on: intention to deceive, quantity of seized drugs, presence of expected therapeutic effect or toxic ingredients, previous criminal records, cooperativeness with Customs officers, honest confessions, pleas of guilty, types of drugs, and precautionary measures to prevent sale of counterfeit drugs. Stakeholders’ perceptions were explored with respect to legislation regarding the scale and significance of the counterfeit drug problem, penalties and deterrents, drug-specific legislation and authority, and inspections and enforcement. To plug the loopholes, a specific law with heavy penalties should be adopted. This could be supplemented by non-legal measures like education of judges, lawyers, and the public; publishing the names of offending pharmacies; and emphasising the role of pharmacists to the public.
Implementation of a Legionella Ordinance for Multifamily Housing, Garland, Texas.
Whitney, Ellen A; Blake, Sarah; Berkelman, Ruth L
The incidence of legionellosis has sharply increased in the United States as a result of contaminated water systems. Jurisdictions across the country are considering whether to develop and implement regulations to protect individuals against Legionnaires' disease with its associated high morbidity and mortality. This article sheds light on the implementation and effectiveness of a 2005 citywide Legionella testing mandate of multifamily housing cooling towers in Garland, Texas. This ordinance has been in place for more than 10 years and represents the first of its kind in the United States to mandate routine testing of cooling towers for Legionella in multifamily housing. We utilized a mix of both qualitative and quantitative methods to explore the development, adoption, and implementation of the ordinance. Phone interviews were conducted with individuals from the City of Garland Health Department and apartment managers. Quantitative data included public health surveillance data on legionellosis. Barriers and facilitators of implementation, number and percentage of cooling towers from multifamily housing units that tested positive for Legionella by year, and number of legionellosis cases by year in Garland, Texas. Study outcomes highlight key themes that facilitated the successful implementation of the Legionella testing mandate, including the importance of timing, leadership support, stakeholder engagement, and education and outreach. The number of contaminated cooling towers was reduced over time. Mandatory monitoring for legionella in a local jurisdiction may result in reduced risk of legionellosis from cooling towers through raising awareness and education of building owners and managers about the need to prevent, detect, and remediate legionella contamination in their building water systems. Garland, Texas, broke new ground in the United States in moving toward primary prevention of legionellosis. The ordinance may be useful both in serving to educate and increase awareness about the need for Legionella prevention and to monitor effectiveness of maintenance procedures.
Carricarte Naranjo, Claudia; Sanchez-Rodriguez, Lazaro M; Brown Martínez, Marta; Estévez Báez, Mario; Machado García, Andrés
2017-07-01
Heart rate variability (HRV) analysis is a relevant tool for the diagnosis of cardiovascular autonomic neuropathy (CAN). To our knowledge, no previous investigation on CAN has assessed the complexity of HRV from an ordinal perspective. Therefore, the aim of this work is to explore the potential of permutation entropy (PE) analysis of HRV complexity for the assessment of CAN. For this purpose, we performed a short-term PE analysis of HRV in healthy subjects and type 1 diabetes mellitus patients, including patients with CAN. Standard HRV indicators were also calculated in the control group. A discriminant analysis was used to select the variables combination with best discriminative power between control and CAN patients groups, as well as for classifying cases. We found that for some specific temporal scales, PE indicators were significantly lower in CAN patients than those calculated for controls. In such cases, there were ordinal patterns with high probabilities of occurrence, while others were hardly found. We posit this behavior occurs due to a decrease of HRV complexity in the diseased system. Discriminant functions based on PE measures or probabilities of occurrence of ordinal patterns provided an average of 75% and 96% classification accuracy. Correlations of PE and HRV measures showed to depend only on temporal scale, regardless of pattern length. PE analysis at some specific temporal scales, seem to provide additional information to that obtained with traditional HRV methods. We concluded that PE analysis of HRV is a promising method for the assessment of CAN. Copyright © 2017 Elsevier Ltd. All rights reserved.
Wang, Ling; Xia, Jie-lai; Yu, Li-li; Li, Chan-juan; Wang, Su-zhen
2008-06-01
To explore several numerical methods of ordinal variable in one-way ordinal contingency table and their interrelationship, and to compare corresponding statistical analysis methods such as Ridit analysis and rank sum test. Formula deduction was based on five simplified grading approaches including rank_r(i), ridit_r(i), ridit_r(ci), ridit_r(mi), and table scores. Practical data set was verified by SAS8.2 in clinical practice (to test the effect of Shiwei solution in treatment for chronic tracheitis). Because of the linear relationship of rank_r(i) = N ridit_r(i) + 1/2 = N ridit_r(ci) = (N + 1) ridit_r(mi), the exact chi2 values in Ridit analysis based on ridit_r(i), ridit_r(ci), and ridit_r(mi), were completely the same, and they were equivalent to the Kruskal-Wallis H test. Traditional Ridit analysis was based on ridit_r(i), and its corresponding chi2 value calculated with an approximate variance (1/12) was conservative. The exact chi2 test of Ridit analysis should be used when comparing multiple groups in the clinical researches because of its special merits such as distribution of mean ridit value on (0,1) and clear graph expression. The exact chi2 test of Ridit analysis can be output directly by proc freq of SAS8.2 with ridit and modridit option (SCORES =). The exact chi2 test of Ridit analysis is equivalent to the Kruskal-Wallis H test, and should be used when comparing multiple groups in the clinical researches.
Audiovisual Integration in Children Listening to Spectrally Degraded Speech
ERIC Educational Resources Information Center
Maidment, David W.; Kang, Hi Jee; Stewart, Hannah J.; Amitay, Sygal
2015-01-01
Purpose: The study explored whether visual information improves speech identification in typically developing children with normal hearing when the auditory signal is spectrally degraded. Method: Children (n = 69) and adults (n = 15) were presented with noise-vocoded sentences from the Children's Co-ordinate Response Measure (Rosen, 2011) in…
Care co-ordination for older people in the third sector: scoping the evidence.
Abendstern, Michele; Hughes, Jane; Jasper, Rowan; Sutcliffe, Caroline; Challis, David
2018-05-01
The third sector has played a significant role internationally in the delivery of adult social care services for many years. Its contribution to care co-ordination activities for older people, however, in England and elsewhere, is relatively unknown. A scoping review was therefore conducted to ascertain the character of the literature, the nature and extent of third sector care co-ordination activity, and to identify evidence gaps. It was undertaken between autumn 2013 and summer 2014 and updated with additional searches in 2016. Electronic and manual searches of international literature using distinct terms for different approaches to care co-ordination were undertaken. From a total of 835 papers, 26 met inclusion criteria. Data were organised in relation to care co-ordination approaches, types of third sector organisation and care recipients. Papers were predominantly from the UK and published this century. Key findings included that: a minority of literature focused specifically on older people and that those doing so described only one care co-ordination approach; third sector services tended to be associated with independence and person-centred practice; and working with the statutory sector, a prerequisite of care co-ordination, was challenging and required a range of features to be in place to support effective partnerships. Strengths and weaknesses of care co-ordination practice in the third sector according to key stakeholder groups were also highlighted. Areas for future research included the need for: a specific focus on older people's experiences; an investigation of workforce issues; detailed examination of third sector practices, outcomes and costs; interactions with the statutory sector; and an examination of quality assurance systems and their appropriateness to third sector practice. The main implication of the findings is a need to nurture variety within the third sector in order to provide older people and other adults with the range of service options desired. © 2017 John Wiley & Sons Ltd.
King, Timothy L.; Henderson, Anne P.; Kynard, Boyd E.; Kieffer, Micah C.; Peterson, Douglas L.; Aunins, Aaron W.; Brown, Bonnie L.
2014-01-01
The shortnose sturgeon, Acipenser brevirostrum, oft considered a phylogenetic relic, is listed as an “endangered species threatened with extinction” in the US and “Vulnerable” on the IUCN Red List. Effective conservation of A. brevirostrum depends on understanding its diversity and evolutionary processes, yet challenges associated with the polyploid nature of its nuclear genome have heretofore limited population genetic analysis to maternally inherited haploid characters. We developed a suite of polysomic microsatellite DNA markers and characterized a sample of 561 shortnose sturgeon collected from major extant populations along the North American Atlantic coast. The 181 alleles observed at 11 loci were scored as binary loci and the data were subjected to multivariate ordination, Bayesian clustering, hierarchical partitioning of variance, and among-population distance metric tests. The methods uncovered moderately high levels of gene diversity suggesting population structuring across and within three metapopulations (Northeast, Mid-Atlantic, and Southeast) that encompass seven demographically discrete and evolutionarily distinct lineages. The predicted groups are consistent with previously described behavioral patterns, especially dispersal and migration, supporting the interpretation that A. brevirostrum exhibit adaptive differences based on watershed. Combined with results of prior genetic (mitochondrial DNA) and behavioral studies, the current work suggests that dispersal is an important factor in maintaining genetic diversity in A. brevirostrum and that the basic unit for conservation management is arguably the local population.
Pham, Huyen Tran; Minh, Tran Hung; Krause, Kathleen H.; Schuler, Sidney Ruth; Anh, Hoang Tu; VanderEnde, Kristin; Kramer, Michael R.
2014-01-01
Purpose We assess the association of men's exposure to violence in childhood--witnessing physical violence against one’s mother and being hit or beaten by a parent or adult relative--with their attitudes about intimate partner violence (IPV) against women. We explore whether men’s perpetration of IPV mediates this relationship and whether men’s attitudes about IPV mediate any relationship of exposure to violence in childhood with perpetration of IPV. Methods 522 married men 18–51 years in Vietnam were interviewed. Multivariate regressions for ordinal and binary responses were estimated to assess these relationships. Results Compared to men experiencing neither form of violence in childhood, men experiencing either or both had higher adjusted odds of reporting more reasons to hit a wife (aORs, 95%CIs: 1.43, 1.03–2.00 and 1.66, 1.05–2.64, respectively). Men’s lifetime perpetration of IPV accounted fully for these associations. Compared to men experiencing neither form of violence in childhood, men experiencing either or both had higher adjusted odds of ever perpetrating IPV (aORs, 95%CIs: 3.28, 2.15–4.99 and 4.56, 2.90–7.17, respectively). Attitudes about IPV modestly attenuated these associations. Conclusion Addressing violence in childhood is needed to change men’s risk of perpetrating IPV and greater subsequent justification of it. PMID:24630242
King, Tim L; Henderson, Anne P; Kynard, Boyd E; Kieffer, Micah C; Peterson, Douglas L; Aunins, Aaron W; Brown, Bonnie L
2014-01-01
The shortnose sturgeon, Acipenser brevirostrum, oft considered a phylogenetic relic, is listed as an "endangered species threatened with extinction" in the US and "Vulnerable" on the IUCN Red List. Effective conservation of A. brevirostrum depends on understanding its diversity and evolutionary processes, yet challenges associated with the polyploid nature of its nuclear genome have heretofore limited population genetic analysis to maternally inherited haploid characters. We developed a suite of polysomic microsatellite DNA markers and characterized a sample of 561 shortnose sturgeon collected from major extant populations along the North American Atlantic coast. The 181 alleles observed at 11 loci were scored as binary loci and the data were subjected to multivariate ordination, Bayesian clustering, hierarchical partitioning of variance, and among-population distance metric tests. The methods uncovered moderately high levels of gene diversity suggesting population structuring across and within three metapopulations (Northeast, Mid-Atlantic, and Southeast) that encompass seven demographically discrete and evolutionarily distinct lineages. The predicted groups are consistent with previously described behavioral patterns, especially dispersal and migration, supporting the interpretation that A. brevirostrum exhibit adaptive differences based on watershed. Combined with results of prior genetic (mitochondrial DNA) and behavioral studies, the current work suggests that dispersal is an important factor in maintaining genetic diversity in A. brevirostrum and that the basic unit for conservation management is arguably the local population.
Moore, Stephanie N.; Hawley, Gregory D.; Smith, Emily N.; Mignemi, Nicholas A.; Ihejirika, Rivka C.; Yuasa, Masato; Cates, Justin M. M.; Liu, Xulei; Schoenecker, Jonathan G.
2016-01-01
Introduction Soft tissue calcification, including both dystrophic calcification and heterotopic ossification, may occur following injury. These lesions have variable fates as they are either resorbed or persist. Persistent soft tissue calcification may result in chronic inflammation and/or loss of function of that soft tissue. The molecular mechanisms that result in the development and maturation of calcifications are uncertain. As a result, directed therapies that prevent or resorb soft tissue calcifications remain largely unsuccessful. Animal models of post-traumatic soft tissue calcification that allow for cost-effective, serial analysis of an individual animal over time are necessary to derive and test novel therapies. We have determined that a cardiotoxin-induced injury of the muscles in the posterior compartment of the lower extremity represents a useful model in which soft tissue calcification develops remote from adjacent bones, thereby allowing for serial analysis by plain radiography. The purpose of the study was to design and validate a method for quantifying soft tissue calcifications in mice longitudinally using plain radiographic techniques and an ordinal scoring system. Methods Muscle injury was induced by injecting cardiotoxin into the posterior compartment of the lower extremity in mice susceptible to developing soft tissue calcification. Seven days following injury, radiographs were obtained under anesthesia. Multiple researchers applied methods designed to standardize post-image processing of digital radiographs (N = 4) and quantify soft tissue calcification (N = 6) in these images using an ordinal scoring system. Inter- and intra-observer agreement for both post-image processing and the scoring system used was assessed using weighted kappa statistics. Soft tissue calcification quantifications by the ordinal scale were compared to mineral volume measurements (threshold 450.7mgHA/cm3) determined by μCT. Finally, sample-size calculations necessary to discriminate between a 25%, 50%, 75%, and 100% difference in STiCSS score 7 days following burn/CTX induced muscle injury were determined. Results Precision analysis demonstrated substantial to good agreement for both post-image processing (κ = 0.73 to 0.90) and scoring (κ = 0.88 to 0.93), with low inter- and intra-observer variability. Additionally, there was a strong correlation in quantification of soft tissue calcification between the ordinal system and by mineral volume quantification by μCT (Spearman r = 0.83 to 0.89). The ordinal scoring system reliably quantified soft tissue calcification in a burn/CTX-induced soft tissue calcification model compared to non-injured controls (Mann-Whitney rank test: P = 0.0002, ***). Sample size calculations revealed that 6 mice per group would be required to detect a 50% difference in STiCSS score with a power of 0.8. Finally, the STiCSS was demonstrated to reliably quantify soft tissue calcification [dystrophic calcification and heterotopic ossification] by radiographic analysis, independent of the histopathological state of the mineralization. Conclusions Radiographic analysis can discriminate muscle injury-induced soft tissue calcification from adjacent bone and follow its clinical course over time without requiring the sacrifice of the animal. While the STiCSS cannot identify the specific type of soft tissue calcification present, it is still a useful and valid method by which to quantify the degree of soft tissue calcification. This methodology allows for longitudinal measurements of soft tissue calcification in a single animal, which is relatively less expensive, less time-consuming, and exposes the animal to less radiation than in vivo μCT. Therefore, this high-throughput, longitudinal analytic method for quantifying soft tissue calcification is a viable alternative for the study of soft tissue calcification. PMID:27438007
Assessing ecological integrity of Ozark rivers to determine suitability for protective status
Radwell, A.J.; Kwak, T.J.
2005-01-01
Preservation of extraordinary natural resources, protection of water quality, and restoration of impaired waters require a strategy to identify and protect least-disturbed streams and rivers. We applied two objective, quantitative methods to determine stream ecological integrity of headwater reaches of 10 Ozark rivers, 5 with Wild and Scenic River federal protective status. Thirty-four variables representing macroinvertebrate and fish assemblage characteristics, in-stream habitat, riparian vegetation, water quality, and watershed attributes were quantified for each river and analyzed using two multivariate approaches. The first approach, cluster and discriminant analyses, identified two groups of river with only one variable (% forested watershed) reliably distinguishing groups. Our second approach employed ordinal scaling to compare variables for each river to conceptually ideal conditions that were developed as a composite of optimal attributes among the 10 rivers. The composite distance of each river from ideal was then calculated using a unidimensional ranking technique. Two rivers without Wild and Scenic River designation ranked highest relative to ideal (highest ecological integrity), and two others, also without designation, ranked most distant from ideal (lowest ecological integrity). Fish density, number of intolerant fish species, and invertebrate density were influential biotic variables for scaling. Contributing physical variables included riparian forest cover, water nitrate concentration, water turbidity, percentage of forested watershed, percentage of private land ownership, and road density. These methods provide a framework for refinement and application in other regions to facilitate the process of establishing least-disturbed reference conditions and identifying rivers for protection and restoration. ?? 2005 Springer Science+Business Media, Inc.
[What factors help to explain satisfaction with Primary Health care in Spain?].
Arrazola-Vacas, M; de Hevia-Payá, J; Rodríguez-Esteban, L
2015-01-01
To find out the factors that determine satisfaction with public primary health care in Spain. The work has considered a wide group of potential determining factors of that satisfaction, which are organised into 3 blocks of variables: Those related to the perceived quality in the care received, socioeconomic, and those relative to the state of health. The micro data of the Barómetro Sanitario (BS) of 2013, which are representative at a national level, were employed. After a prior first descriptive analysis, 2 multivariate models were estimated: One in which satisfaction is considered as being of a cardinal nature (regression model), and another in which it is contemplated as being of an ordinal nature (ordered probit model). There were practically no differences between the results obtained with one or other of the multivariate models. Not all the variables considered were statistically significant. Of the 3 blocks of variables studied, the one related to the perceived quality in the care received in the health centre exerts the greatest relevance in the explanation of satisfaction. The results obtained show that, by means of the management of the variables related to the perception of quality of care in health centres, public administrators and health professionals may have a highly favourable influence on the levels of satisfaction of primary health care patients. Copyright © 2015 SECA. Published by Elsevier Espana. All rights reserved.
Derksen, V F A M; Ajeganova, S; Trouw, L A; van der Helm-van Mil, A H M; Hafström, I; Huizinga, T W J; Toes, R E M; Svensson, B; van der Woude, D
2017-04-01
In rheumatoid arthritis (RA), seropositive and seronegative disease may be two entities with different underlying pathophysiological mechanisms, long-term outcomes and disease presentations. However, the effect of the conjoint presence of multiple autoantibodies, as proxy for a more pronounced humoral autoimmune response, on clinical phenotype remains unclear. Therefore, this study investigates the association between the number of autoantibodies and initial clinical presentation in two independent cohorts of patients with early RA. Autoantibody status (rheumatoid factor, anticitrullinated protein antibodies and anticarbamylated protein antibodies) was determined at baseline in the Leiden Early Arthritis Cohort (n=828) and the Swedish BARFOT (Better Anti-Rheumatic Farmaco-Therapy, n=802) study. The association between the number of autoantibodies and baseline clinical characteristics was investigated using univariable and multivariable ordinal regression. In both cohorts, the following independent associations were found in multivariable analysis: patients with a higher number of RA-associated antibodies were younger, more often smokers, had a longer symptom duration and a higher erythrocyte sedimentation rate at presentation compared with patients with few autoantibodies. The number of autoantibodies, reflecting the breadth of the humoral autoimmune response, is associated with the clinical presentation of RA. Predisease pathophysiology is thus reflected by the initial clinical phenotype. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Jackson, Dan; White, Ian R; Riley, Richard D
2013-01-01
Multivariate meta-analysis is becoming more commonly used. Methods for fitting the multivariate random effects model include maximum likelihood, restricted maximum likelihood, Bayesian estimation and multivariate generalisations of the standard univariate method of moments. Here, we provide a new multivariate method of moments for estimating the between-study covariance matrix with the properties that (1) it allows for either complete or incomplete outcomes and (2) it allows for covariates through meta-regression. Further, for complete data, it is invariant to linear transformations. Our method reduces to the usual univariate method of moments, proposed by DerSimonian and Laird, in a single dimension. We illustrate our method and compare it with some of the alternatives using a simulation study and a real example. PMID:23401213
Measures of Agreement Between Many Raters for Ordinal Classifications
Nelson, Kerrie P.; Edwards, Don
2015-01-01
Screening and diagnostic procedures often require a physician's subjective interpretation of a patient's test result using an ordered categorical scale to define the patient's disease severity. Due to wide variability observed between physicians’ ratings, many large-scale studies have been conducted to quantify agreement between multiple experts’ ordinal classifications in common diagnostic procedures such as mammography. However, very few statistical approaches are available to assess agreement in these large-scale settings. Existing summary measures of agreement rely on extensions of Cohen's kappa [1 - 5]. These are prone to prevalence and marginal distribution issues, become increasingly complex for more than three experts or are not easily implemented. Here we propose a model-based approach to assess agreement in large-scale studies based upon a framework of ordinal generalized linear mixed models. A summary measure of agreement is proposed for multiple experts assessing the same sample of patients’ test results according to an ordered categorical scale. This measure avoids some of the key flaws associated with Cohen's kappa and its extensions. Simulation studies are conducted to demonstrate the validity of the approach with comparison to commonly used agreement measures. The proposed methods are easily implemented using the software package R and are applied to two large-scale cancer agreement studies. PMID:26095449
Buettner-Schmidt, Kelly; Lobo, Marie L; Travers, Mark J; Boursaw, Blake
2015-08-01
The purpose of this cross-sectional study in a stratified random sample of 135 bars and restaurants in North Dakota was to describe factors that influenced tobacco smoke pollution levels in the venues; to compare the quantity of tobacco smoke pollution by rurality and by presence of local ordinances; and to assess compliance with state and local laws. In data collection in 2012, we measured the indoor air quality indicator of particulate matter (2.5 microns aerodynamic diameter or smaller), calculated average smoking density and occupant density, and determined compliance with state and local smoking ordinances using observational methods. As rurality increased, tobacco smoke pollution in bars increased. A significant association was found between stringency of local laws and level of tobacco smoke pollution, but the strength of the association varied by venue type. Compliance was significantly lower in venues in communities without local ordinances. Controlling for venue type, 69.2% of smoke-free policy's impact on tobacco smoke pollution levels was mediated by observed smoking. This study advances scientific knowledge on the factors influencing tobacco smoke pollution and informs public health advocates and decision makers on policy needs, especially in rural areas. © 2015 Wiley Periodicals, Inc.
ERIC Educational Resources Information Center
Koehle, Gregory M.
2011-01-01
This research involves a legal impact study of the State College Nuisance Property Ordinance and an assessment of State College Rental Property Managers in the role of place manager/intimate handler of offender. The impact of the Ordinance was assessed by employing an interrupted time series design which examined five years of pre-ordinance…
Continuous Coordination Tools and their Evaluation
NASA Astrophysics Data System (ADS)
Sarma, Anita; Al-Ani, Ban; Trainer, Erik; Silva Filho, Roberto S.; da Silva, Isabella A.; Redmiles, David; van der Hoek, André
This chapter discusses a set of co-ordination tools (the Continuous Co-ordination (CC) tool suite that includes Ariadne, Workspace Activity Viewer (WAV), Lighthouse, Palantír, and YANCEES) and details of our evaluation framework for these tools. Specifically, we discuss how we assessed the usefulness and the usability of these tools within the context of a predefined evaluation framework called
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sabot, A.; Petit, A.; Taillebois, J.P.
1996-07-01
This paper summarizes the Electricite de France experience with insulation co-ordination of GIS. After a review of the insulation co-ordination practice mainly dealing with fast front overvoltage and the one minute AC test, some results of the on-site test procedure applied since 30 years are presented and related to the insulation co-ordination practice. The in-service return of experience dealing with dielectric failures is analyzed then the dielectric diagnostic techniques now available are briefly presented with their possibilities and limitations. According to this survey, the expectations of EDF from these diagnostic techniques as well as the new on-site test and on-linemore » monitoring tendencies at EDF are presented.« less
Radiative Transfer Model for Operational Retrieval of Cloud Parameters from DSCOVR-EPIC Measurements
NASA Astrophysics Data System (ADS)
Yang, Y.; Molina Garcia, V.; Doicu, A.; Loyola, D. G.
2016-12-01
The Earth Polychromatic Imaging Camera (EPIC) onboard the Deep Space Climate Observatory (DSCOVR) measures the radiance in the backscattering region. To make sure that all details in the backward glory are covered, a large number of streams is required by a standard radiative transfer model based on the discrete ordinates method. Even the use of the delta-M scaling and the TMS correction do not substantially reduce the number of streams. The aim of this work is to analyze the capability of a fast radiative transfer model to retrieve operationally cloud parameters from EPIC measurements. The radiative transfer model combines the discrete ordinates method with matrix exponential for the computation of radiances and the matrix operator method for the calculation of the reflection and transmission matrices. Standard acceleration techniques as, for instance, the use of the normalized right and left eigenvectors, telescoping technique, Pade approximation and successive-order-of-scattering approximation are implemented. In addition, the model may compute the reflection matrix of the cloud by means of the asymptotic theory, and may use the equivalent Lambertian cloud model. The various approximations are analyzed from the point of view of efficiency and accuracy.
Computing Radiative Transfer in a 3D Medium
NASA Technical Reports Server (NTRS)
Von Allmen, Paul; Lee, Seungwon
2012-01-01
A package of software computes the time-dependent propagation of a narrow laser beam in an arbitrary three- dimensional (3D) medium with absorption and scattering, using the transient-discrete-ordinates method and a direct integration method. Unlike prior software that utilizes a Monte Carlo method, this software enables simulation at very small signal-to-noise ratios. The ability to simulate propagation of a narrow laser beam in a 3D medium is an improvement over other discrete-ordinate software. Unlike other direct-integration software, this software is not limited to simulation of propagation of thermal radiation with broad angular spread in three dimensions or of a laser pulse with narrow angular spread in two dimensions. Uses for this software include (1) computing scattering of a pulsed laser beam on a material having given elastic scattering and absorption profiles, and (2) evaluating concepts for laser-based instruments for sensing oceanic turbulence and related measurements of oceanic mixed-layer depths. With suitable augmentation, this software could be used to compute radiative transfer in ultrasound imaging in biological tissues, radiative transfer in the upper Earth crust for oil exploration, and propagation of laser pulses in telecommunication applications.
Introduction to the Theory of Atmospheric Radiative Transfer
NASA Technical Reports Server (NTRS)
Buglia, J. J.
1986-01-01
The fundamental physical and mathematical principles governing the transmission of radiation through the atmosphere are presented, with emphasis on the scattering of visible and near-IR radiation. The classical two-stream, thin-atmosphere, and Eddington approximations, along with some of their offspring, are developed in detail, along with the discrete ordinates method of Chandrasekhar. The adding and doubling methods are discussed from basic principles, and references for further reading are suggested.
NASA Astrophysics Data System (ADS)
Zuhdi, Shaifudin; Saputro, Dewi Retno Sari
2017-03-01
GWOLR model used for represent relationship between dependent variable has categories and scale of category is ordinal with independent variable influenced the geographical location of the observation site. Parameters estimation of GWOLR model use maximum likelihood provide system of nonlinear equations and hard to be found the result in analytic resolution. By finishing it, it means determine the maximum completion, this thing associated with optimizing problem. The completion nonlinear system of equations optimize use numerical approximation, which one is Newton Raphson method. The purpose of this research is to make iteration algorithm Newton Raphson and program using R software to estimate GWOLR model. Based on the research obtained that program in R can be used to estimate the parameters of GWOLR model by forming a syntax program with command "while".
Statistical Optimality in Multipartite Ranking and Ordinal Regression.
Uematsu, Kazuki; Lee, Yoonkyung
2015-05-01
Statistical optimality in multipartite ranking is investigated as an extension of bipartite ranking. We consider the optimality of ranking algorithms through minimization of the theoretical risk which combines pairwise ranking errors of ordinal categories with differential ranking costs. The extension shows that for a certain class of convex loss functions including exponential loss, the optimal ranking function can be represented as a ratio of weighted conditional probability of upper categories to lower categories, where the weights are given by the misranking costs. This result also bridges traditional ranking methods such as proportional odds model in statistics with various ranking algorithms in machine learning. Further, the analysis of multipartite ranking with different costs provides a new perspective on non-smooth list-wise ranking measures such as the discounted cumulative gain and preference learning. We illustrate our findings with simulation study and real data analysis.
Zhang, Fanghong; Miyaoka, Etsuo; Huang, Fuping; Tanaka, Yutaka
2015-01-01
The problem for establishing noninferiority is discussed between a new treatment and a standard (control) treatment with ordinal categorical data. A measure of treatment effect is used and a method of specifying noninferiority margin for the measure is provided. Two Z-type test statistics are proposed where the estimation of variance is constructed under the shifted null hypothesis using U-statistics. Furthermore, the confidence interval and the sample size formula are given based on the proposed test statistics. The proposed procedure is applied to a dataset from a clinical trial. A simulation study is conducted to compare the performance of the proposed test statistics with that of the existing ones, and the results show that the proposed test statistics are better in terms of the deviation from nominal level and the power.
Display Parameters and Requirements
NASA Astrophysics Data System (ADS)
Bahadur, Birendra
The following sections are included: * INTRODUCTION * HUMAN FACTORS * Anthropometry * Sensory * Cognitive * Discussions * THE HUMAN VISUAL SYSTEM - CAPABILITIES AND LIMITATIONS * Cornea * Pupil and Iris * Lens * Vitreous Humor * Retina * RODS - NIGHT VISION * CONES - DAY VISION * RODS AND CONES - TWILIGHT VISION * VISUAL PIGMENTS * MACULA * BLOOD * CHOROID COAT * Visual Signal Processing * Pathways to the Brain * Spatial Vision * Temporal Vision * Colour Vision * Colour Blindness * DICHROMATISM * Protanopia * Deuteranopia * Tritanopia * ANOMALOUS TRICHROMATISM * Protanomaly * Deuteranomaly * Tritanomaly * CONE MONOCHROMATISM * ROD MONOCHROMATISM * Using Colour Effectively * COLOUR MIXTURES AND THE CHROMATICITY DIAGRAM * Colour Matching Functions and Chromaticity Co-ordinates * CIE 1931 Colour Space * CIE PRIMARIES * CIE COLOUR MATCHING FUNCTIONS AND CHROMATICITY CO-ORDINATES * METHODS FOR DETERMINING TRISTIMULUS VALUES AND COLOUR CO-ORDINATES * Spectral Power Distribution Method * Filter Method * CIE 1931 CHROMATICITY DIAGRAM * ADDITIVE COLOUR MIXTURE * CIE 1976 Chromaticity Diagram * CIE Uniform Colour Spaces and Colour Difference Formulae * CIELUV OR L*u*v* * CIELAB OR L*a*b* * CIE COLOUR DIFFERENCE FORMULAE * Colour Temperature and CIE Standard Illuminants and source * RADIOMETRIC AND PHOTOMETRIC QUANTITIES * Photopic (Vλ and Scotopic (Vλ') Luminous Efficiency Function * Photometric and Radiometric Flux * Luminous and Radiant Intensities * Incidence: Illuminance and Irradiance * Exitance or Emittance (M) * Luminance and Radiance * ERGONOMIC REQUIREMENTS OF DISPLAYS * ELECTRO-OPTICAL PARAMETERS AND REQUIREMENTS * Contrast and Contrast Ratio * Luminance and Brightness * Colour Contrast and Chromaticity * Glare * Other Aspects of Legibility * SHAPE AND SIZE OF CHARACTERS * DEFECTS AND BLEMISHES * FLICKER AND DISTORTION * ANGLE OF VIEW * Switching Speed * Threshold and Threshold Characteristic * Measurement Techniques For Electro-optical Parameters * RADIOMETRIC MEASUREMENTS * Broadband Radiometry or Filtered Photodetector Radiometric Method * Spectroradiometric Method * PHOTOMETRIC MEASUREMENTS * COLOUR MEASUREMENTS * LUMINANCE, CONTRAST RATIO, THRESHOLD CHARACTERISTIC AND POLAR PLOT * SWITCHING SPEED * ELECTRICAL AND LIFE PARAMETERS AND REQUIREMENTS * Operating Voltage, Current Drainage and Power Consumption * Operating Frequency * Life Expectancy * LCD FAILURE MODES * Liquid Crystal Materials * Substrate Glass * Electrode Patterns * Alignment and Aligning Material * Peripheral and End Plug Seal * Spacers * Crossover Material * Polarizers and Reflectors * Connectors * Heater * Colour Filters * Backlighting System * Explanation For Some of the Observed Defects * BLOOMING PIXELS * POLARIZER RELATED DEFECTS * DIFFERENTIAL THERMAL EXPANSION RELATED DEFECTS * ELECTROCHEMICAL AND ELECTROHYDRODYNAMIC RELATED DEFECTS * REVERSE TWIST AND REVERSE TILT * MEMORY OR REMINISCENT CONTRAST * LCD RELIABILRY AND ACCELERATED LIFE TESTING * ACKNOWLEDGEMENTS * REFERENCES * APPENDIX
A multivariate model and statistical method for validating tree grade lumber yield equations
Donald W. Seegrist
1975-01-01
Lumber yields within lumber grades can be described by a multivariate linear model. A method for validating lumber yield prediction equations when there are several tree grades is presented. The method is based on multivariate simultaneous test procedures.
Chauvin, K McManus; Asner, G P; Martin, R E; Kress, W J; Wright, S J; Field, C B
2018-03-01
Trade-offs among plant functional traits indicate diversity in plant strategies of growth and survival. The leaf economics spectrum (LES) reflects a trade-off between short-term carbon gain and long-term leaf persistence. A related trade-off, between foliar growth and anti-herbivore defense, occurs among plants growing in contrasting resource regimes, but it is unclear whether this trade-off is maintained within plant communities, where resource gradients are minimized. The LES and the growth-defense trade-off involve related traits, but the extent to which these trade-off dimensions are correlated is poorly understood. We assessed the relationship between leaf economic and anti-herbivore defense traits among sunlit foliage of 345 canopy trees in 83 species on Barro Colorado Island, Panama. We quantified ten traits related to resource allocation and defense, and identified patterns of trait co-variation using multivariate ordination. We tested whether traits and ordination axes were correlated with patterns of phylogenetic relatedness, juvenile demographic trade-offs, or topo-edaphic variation. Two independent axes described ~ 60% of the variation among canopy trees. Axis 1 revealed a trade-off between leaf nutritional and structural investment, consistent with the LES. Physical defense traits were largely oriented along this axis. Axis 2 revealed a trade-off between investments in phenolic defenses versus other foliar defenses, which we term the leaf defense spectrum. Phylogenetic relationships and topo-edaphic variation largely did not explain trait co-variation. Our results suggest that some trade-offs among the growth and defense traits of outer-canopy trees may be captured by the LES, while others may occur along additional resource allocation dimensions.
Vleeshouwers, Jolien; Knardahl, Stein; Christensen, Jan Olav
2016-04-01
This prospective cohort study examined previously underexplored relations between psychological/social work factors and troubled sleep in order to provide practical information about specific, modifiable factors at work. A comprehensive evaluation of a range of psychological/social work factors was obtained by several designs; i.e., cross-sectional analyses at baseline and follow-up, prospective analyses with baseline predictors (T1), prospective analyses with average exposure across waves as predictor ([T1 + T2] / 2), and prospective analyses with change in exposure from baseline to follow-up as predictor. Participants consisted of a sample of Norwegian employees from a broad spectrum of occupations, who completed a questionnaire at two points in time, approximately two years apart. Cross-sectional analyses at T1 comprised 7,459 participants, cross-sectional analyses at T2 included 6,688 participants. Prospective analyses comprised a sample 5,070 of participants who responded at both T1 and T2. Univariable and multivariable ordinal logistic regressions were performed. Thirteen psychological/social work factors and two aspects of troubled sleep, namely difficulties initiating sleep and disturbed sleep, were studied. Ordinal logistic regressions revealed statistically significant associations for all psychological and social work factors in at least one of the analyses. Psychological and social work factors predicted sleep problems in the short term as well as the long term. All work factors investigated showed statistically significant associations with both sleep items, however quantitative job demands, decision control, role conflict, and support from superior were the most robust predictors and may therefore be suitable targets of interventions aimed at improving employee sleep. © 2016 Associated Professional Sleep Societies, LLC.
Kim, O-S; Kim, M S; Lee, J E; Jung, H
2016-12-01
The prevalence of night-eating syndrome (NES) and depression is increasing worldwide. Although nurses, in particular, are exposed to work in an environment of irregular eating, shift work, and stressful settings, limited research exist. In fact, the prevalence of NES among Korean nurses has never been reported. The aim of this study was to determine the prevalence of NES as well as the association between NES and severity of self-reported depressive symptoms among South Korean female nurses. The Korea Nurses' Health Study, following the protocols of the Nurses' Health Study led by the Harvard University, collected data on Korean female nurses. Survey responses from 3617 participants were included, and 404 responses were analyzed in this cross-sectional study using propensity score matching. Descriptive, Spearman's and Cramer's correlations, propensity score matching, and multivariable ordinal logistic regression were conducted as statistical analysis. The prevalence of both NES and self-reported depressive symptoms among Korean female nurses were higher compared with nurses in prior studies. Nurses with NES were 1.65 times more likely to have greater severity of depressive symptoms than those without NES (95% confidence interval [1.19-2.10], odds ratio = 1.65) after adjusting for covariates including sociodemographic characteristics, health behavioural factors, and shift work. This study suggests significant association between NES and the severity of self-reported depressive symptoms among Korean female nurses after adjusting for covariates. Policy makers and hospital managers need to develop strategies to reduce depression and NES among nurses for enhancement of nurses' mental and physical health as well as for improvement of care quality. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Luo, Xiaoyun; Zhang, Fuxian; Zhang, Changming; Hu, Lu; Feng, Yaping; Liang, Gangzhu; Niu, Luyuan; Zhang, Huan; Cheng, Long; Qi, Haoshan
2015-08-01
To identify the risk factors associated with the severity of pulmonary embolism among patients with deep venous thrombosis of lower extremities. This prospective study enrolled 208 patients with acute deep venous thrombosis to screen for pulmonary embolism between July 2010 and July 2012 in Beijing Shijitan Hospital. There were 101 male and 107 female patients, with a mean age of (59 ± 16) years. Gender, age, extension, side of lower extremities of deep venous thrombosis was analyzed by χ² test. Ordinal Logistic regression was used to determine risk factors associated with severity of pulmonary embolism. There were 83 patients with iliofemoral deep venous thrombosis, 102 patients with femoropopliteal and 23 patients with calf deep venous thrombosis. Pulmonary embolism was detected in 70 patients with the incidence of 33.7%. Pulmonary embolism was significantly correlated with extension (χ² = 17.286, P = 0.004) and sides (χ² = 15.602, P = 0.008) of deep venous thrombosis, not with age (χ² = 7.099, P = 0.260), gender (χ² = 7.014, P = 0.067), thrombotic risk factors (χ² = 3.335, P = 0.345) in univariate analysis. Results of multivariate ordinal logistic regression showed that iliofemoral vein thrombosis (OR = 6.172, 95% CI: 1.590 to 23.975, P = 0.009) and bilateral venous thrombosis (OR = 7.140, 95% CI: 2.406 to 24.730, P = 0.001) are associated with more serious pulmonary embolism. Incidence of pulmonary embolism is still high in patients with deep venous thrombosis. Extensive iliofemoral and bilateral vein thrombosis may increase risk of severity of pulmonary embolism. Clinicians should pay more attention to these high-risk patients.
Compliance with the City of Chicago's partial ban on menthol cigarette sales.
Czaplicki, Lauren; Cohen, Joanna E; Jones, Miranda R; Clegg Smith, Katherine; Rutkow, Lainie; Owczarzak, Jill
2018-05-31
In the USA, menthol cigarettes are associated with smoking initiation and decreased likelihood of cessation, particularly for low-income and non-White populations. Local ordinances to restrict menthol cigarette sales are an emergent policy option. In July 2016, Chicago, Illinois became the first major US city to ban menthol cigarette sales within 500 feet of schools. This study assessed ban compliance in June 2017. We randomly selected 100 of 154 stores within 500 feet of a high school. Ninety stores were included in the analysis, excluding permanently closed stores or stores that did not sell tobacco prior to the ban. Compliance was determined by whether a menthol cigarette pack was purchased. We also assessed presence of menthol cigarette replacement packs. Multivariable logistic regression modelled compliance by store type, school (distance to high school, school type) and neighbourhood-level factors (poverty level, proportion of non-White residents). Compliance rate was 57% (weighted, n=53) and no replacement packs were observed. Non-compliant stores were more likely to advertise menthol cigarettes, but ads were present in eight compliant stores. Gas stations had 81% lower odds (OR=0.19, 95% CI 0.06 to 0.58) of complying with the menthol cigarette ban compared with larger/chain stores. School-level and neighbourhood factors were not associated with compliance. The poor compliance observed with Chicago's partial menthol cigarette ban highlights the need for comprehensive efforts. Optimising local resources to target enforcement efforts in gas stations could improve compliance. Ordinances that also restrict advertising could potentially enhance ban impact by reducing exposure to product and promotions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Spatial coding of ordinal information in short- and long-term memory.
Ginsburg, Véronique; Gevers, Wim
2015-01-01
The processing of numerical information induces a spatial response bias: Faster responses to small numbers with the left hand and faster responses to large numbers with the right hand. Most theories agree that long-term representations underlie this so called SNARC effect (Spatial Numerical Association of Response Codes; Dehaene et al., 1993). However, a spatial response bias was also observed with the activation of temporary position-space associations in working memory (ordinal position effect; van Dijck and Fias, 2011). Items belonging to the beginning of a memorized sequence are responded to faster with the left hand side while items at the end of the sequence are responded to faster with the right hand side. The theoretical possibility was put forward that the SNARC effect is an instance of the ordinal position effect, with the empirical consequence that the SNARC effect and the ordinal position effect cannot be observed simultaneously. In two experiments we falsify this claim by demonstrating that the SNARC effect and the ordinal position effect are not mutually exclusive. Consequently, this suggests that the SNARC effect and the ordinal position effect result from the activation of different representations. We conclude that spatial response biases can result from the activation of both pre-existing positions in long-term memory and from temporary space associations in working memory at the same time.
Restaurant volatility and the Iowa City, Iowa, smoke-free restaurant ordinance.
Sheffer, Megan A; Squier, Christopher A; Gilmore, Gary D
2013-01-01
To determine the economic impact of the Iowa City, Iowa, smoke-free restaurant ordinance (IC-SFRO) using an immediate and novel approach. In this retrospective study, food permit licensure served as the measure to assess the IC-SFRO impact. The Iowa City experience provided an excellent experimental setting, as the ordinance was enacted March 1, 2002, and repealed May 7, 2003, because of preemption. The city of Coralville served as a natural control, as it is contiguous to Iowa City, has similar population demographics, and has never enacted a smoke-free restaurant ordinance. Food permit licensure data for all Iowa City and Coralville restaurants were obtained from the Johnson County Health Department. Differences in restaurant volatility were assessed using Fisher's exact probability test. The number of restaurants increased in both Iowa City and Coralville throughout the ordinance period. The ratio of the total number of restaurants in Iowa City to the total number of restaurants in the Iowa City-Coralville metropolitan area remained stable. The proportion of restaurants for each city did not differ significantly during the preordinance, ordinance, and postordinance periods. The IC-SFRO did not adversely impact the restaurant industry in terms of restaurant closures. The Iowa legislature was urged to draft evidence-based legislation, such as amending preemption of the IC-SFRO, to protect and promote the health of its communities.
Multivariate Methods for Meta-Analysis of Genetic Association Studies.
Dimou, Niki L; Pantavou, Katerina G; Braliou, Georgia G; Bagos, Pantelis G
2018-01-01
Multivariate meta-analysis of genetic association studies and genome-wide association studies has received a remarkable attention as it improves the precision of the analysis. Here, we review, summarize and present in a unified framework methods for multivariate meta-analysis of genetic association studies and genome-wide association studies. Starting with the statistical methods used for robust analysis and genetic model selection, we present in brief univariate methods for meta-analysis and we then scrutinize multivariate methodologies. Multivariate models of meta-analysis for a single gene-disease association studies, including models for haplotype association studies, multiple linked polymorphisms and multiple outcomes are discussed. The popular Mendelian randomization approach and special cases of meta-analysis addressing issues such as the assumption of the mode of inheritance, deviation from Hardy-Weinberg Equilibrium and gene-environment interactions are also presented. All available methods are enriched with practical applications and methodologies that could be developed in the future are discussed. Links for all available software implementing multivariate meta-analysis methods are also provided.
Nashimoto, M; Mishima, Y
1988-01-01
Based on recent experimental data about transcription initiation and termination, a model for regulation of mammalian ribosomal DNA transcription is developed using a simple kinetic scheme. In this model, the existence of the transition pathway from the terminator to the promoter increases the rate of ribosomal RNA precursor synthesis. In addition to this 'non-transcribed spacer' traverse of RNA polymerase I, the co-ordination of initiation and termination allows a rapid on/off switch transition from the minimum to the maximum rate of ribosomal RNA precursor synthesis. Furthermore, taking account of the participation of two factors in the termination event, we propose a plausible molecular mechanism for the co-ordination of initiation and termination. This co-ordination is emphasized by repetition of the terminator unit. PMID:3223915
Estimating Achievement Gaps from Test Scores Reported in Ordinal "Proficiency" Categories
ERIC Educational Resources Information Center
Ho, Andrew D.; Reardon, Sean F.
2012-01-01
Test scores are commonly reported in a small number of ordered categories. Examples of such reporting include state accountability testing, Advanced Placement tests, and English proficiency tests. This paper introduces and evaluates methods for estimating achievement gaps on a familiar standard-deviation-unit metric using data from these ordered…
Does the EDI Measure School Readiness in the Same Way across Different Groups of Children?
ERIC Educational Resources Information Center
Guhn, Martin; Gadermann, Anne; Zumbo, Bruno D.
2007-01-01
The present study investigates whether the Early Development Instrument (Offord & Janus, 1999) measures school readiness similarly across different groups of children. We employ ordinal logistic regression to investigate differential item functioning, a method of examining measurement bias. For 40,000 children, our analysis compares groups…
Introduction to Latent Class Analysis with Applications
ERIC Educational Resources Information Center
Porcu, Mariano; Giambona, Francesca
2017-01-01
Latent class analysis (LCA) is a statistical method used to group individuals (cases, units) into classes (categories) of an unobserved (latent) variable on the basis of the responses made on a set of nominal, ordinal, or continuous observed variables. In this article, we introduce LCA in order to demonstrate its usefulness to early adolescence…
ERIC Educational Resources Information Center
Karimi, Hamid; Jones, Mark; O'Brian, Sue; Onslow, Mark
2014-01-01
Background: At present, percent syllables stuttered (%SS) is the gold standard outcome measure for behavioural stuttering treatment research. However, ordinal severity rating (SR) procedures have some inherent advantages over that method. Aims: To establish the relationship between Clinician %SS, Clinician SR and self-reported Speaker SR. To…
Accuracy of the Parallel Analysis Procedure with Polychoric Correlations
ERIC Educational Resources Information Center
Cho, Sun-Joo; Li, Feiming; Bandalos, Deborah
2009-01-01
The purpose of this study was to investigate the application of the parallel analysis (PA) method for choosing the number of factors in component analysis for situations in which data are dichotomous or ordinal. Although polychoric correlations are sometimes used as input for component analyses, the random data matrices generated for use in PA…
31 CFR 215.10 - Agency withholding procedures.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., STATE, CITY AND COUNTY INCOME OR EMPLOYMENT TAXES BY FEDERAL AGENCIES Withholding Agreement § 215.10... compensation, each agency shall use the method prescribed by the State income tax statute or city or county... income tax, or (2) By the city or county ordinance from the compensation of each employee subject to such...
31 CFR 215.10 - Agency withholding procedures.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., STATE, CITY AND COUNTY INCOME OR EMPLOYMENT TAXES BY FEDERAL AGENCIES Withholding Agreement § 215.10... compensation, each agency shall use the method prescribed by the State income tax statute or city or county... income tax, or (2) By the city or county ordinance from the compensation of each employee subject to such...
Principles for valid histopathologic scoring in research
Gibson-Corley, Katherine N.; Olivier, Alicia K.; Meyerholz, David K.
2013-01-01
Histopathologic scoring is a tool by which semi-quantitative data can be obtained from tissues. Initially, a thorough understanding of the experimental design, study objectives and methods are required to allow the pathologist to appropriately examine tissues and develop lesion scoring approaches. Many principles go into the development of a scoring system such as tissue examination, lesion identification, scoring definitions and consistency in interpretation. Masking (a.k.a. “blinding”) of the pathologist to experimental groups is often necessary to constrain bias and multiple mechanisms are available. Development of a tissue scoring system requires appreciation of the attributes and limitations of the data (e.g. nominal, ordinal, interval and ratio data) to be evaluated. Incidence, ordinal and rank methods of tissue scoring are demonstrated along with key principles for statistical analyses and reporting. Validation of a scoring system occurs through two principal measures: 1) validation of repeatability and 2) validation of tissue pathobiology. Understanding key principles of tissue scoring can help in the development and/or optimization of scoring systems so as to consistently yield meaningful and valid scoring data. PMID:23558974
Standardizing the atomic description, axis and centre of biological ion channels.
Kaats, Adrian J; Galiana, Henrietta L; Nadeau, Jay L
2007-09-15
A general representation of the atomic co-ordinates of a biological ion channel is obtained from a definition of channel axis and centre. Through rotation and translation of the channel, its centre becomes the origin of the standard co-ordinate system, and the channel axis becomes the system's z-axis. A method for determining the channel axis and centre based on the concepts of mass centre and mass moment of inertia is presented. The method for determining the channel axis can be directly applied to channels that adhere to two specific conditions regarding their geometry and mass distribution. Specific examples are given for Gramicidin A (GA), and the mammalian potassium channel Kv 1.2. For channels that do not adhere to these conditions, minor modifications of these procedures can be applied in determining the channel axis. Specific examples are given for the outer membrane bacterial porin OmpF, and for the staphylococcal pore-forming toxin alpha-hemolysin (alpha HL). The definitions and procedures presented are made in an effort to establish a standard basis for performing, sharing, and comparing computations in a consistent manner.
Deconstructing multivariate decoding for the study of brain function.
Hebart, Martin N; Baker, Chris I
2017-08-04
Multivariate decoding methods were developed originally as tools to enable accurate predictions in real-world applications. The realization that these methods can also be employed to study brain function has led to their widespread adoption in the neurosciences. However, prior to the rise of multivariate decoding, the study of brain function was firmly embedded in a statistical philosophy grounded on univariate methods of data analysis. In this way, multivariate decoding for brain interpretation grew out of two established frameworks: multivariate decoding for predictions in real-world applications, and classical univariate analysis based on the study and interpretation of brain activation. We argue that this led to two confusions, one reflecting a mixture of multivariate decoding for prediction or interpretation, and the other a mixture of the conceptual and statistical philosophies underlying multivariate decoding and classical univariate analysis. Here we attempt to systematically disambiguate multivariate decoding for the study of brain function from the frameworks it grew out of. After elaborating these confusions and their consequences, we describe six, often unappreciated, differences between classical univariate analysis and multivariate decoding. We then focus on how the common interpretation of what is signal and noise changes in multivariate decoding. Finally, we use four examples to illustrate where these confusions may impact the interpretation of neuroimaging data. We conclude with a discussion of potential strategies to help resolve these confusions in interpreting multivariate decoding results, including the potential departure from multivariate decoding methods for the study of brain function. Copyright © 2017. Published by Elsevier Inc.
Multivariate analysis in thoracic research.
Mengual-Macenlle, Noemí; Marcos, Pedro J; Golpe, Rafael; González-Rivas, Diego
2015-03-01
Multivariate analysis is based in observation and analysis of more than one statistical outcome variable at a time. In design and analysis, the technique is used to perform trade studies across multiple dimensions while taking into account the effects of all variables on the responses of interest. The development of multivariate methods emerged to analyze large databases and increasingly complex data. Since the best way to represent the knowledge of reality is the modeling, we should use multivariate statistical methods. Multivariate methods are designed to simultaneously analyze data sets, i.e., the analysis of different variables for each person or object studied. Keep in mind at all times that all variables must be treated accurately reflect the reality of the problem addressed. There are different types of multivariate analysis and each one should be employed according to the type of variables to analyze: dependent, interdependence and structural methods. In conclusion, multivariate methods are ideal for the analysis of large data sets and to find the cause and effect relationships between variables; there is a wide range of analysis types that we can use.
Correlative and multivariate analysis of increased radon concentration in underground laboratory.
Maletić, Dimitrije M; Udovičić, Vladimir I; Banjanac, Radomir M; Joković, Dejan R; Dragić, Aleksandar L; Veselinović, Nikola B; Filipović, Jelena
2014-11-01
The results of analysis using correlative and multivariate methods, as developed for data analysis in high-energy physics and implemented in the Toolkit for Multivariate Analysis software package, of the relations of the variation of increased radon concentration with climate variables in shallow underground laboratory is presented. Multivariate regression analysis identified a number of multivariate methods which can give a good evaluation of increased radon concentrations based on climate variables. The use of the multivariate regression methods will enable the investigation of the relations of specific climate variable with increased radon concentrations by analysis of regression methods resulting in 'mapped' underlying functional behaviour of radon concentrations depending on a wide spectrum of climate variables. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Multivariate missing data in hydrology - Review and applications
NASA Astrophysics Data System (ADS)
Ben Aissia, Mohamed-Aymen; Chebana, Fateh; Ouarda, Taha B. M. J.
2017-12-01
Water resources planning and management require complete data sets of a number of hydrological variables, such as flood peaks and volumes. However, hydrologists are often faced with the problem of missing data (MD) in hydrological databases. Several methods are used to deal with the imputation of MD. During the last decade, multivariate approaches have gained popularity in the field of hydrology, especially in hydrological frequency analysis (HFA). However, treating the MD remains neglected in the multivariate HFA literature whereas the focus has been mainly on the modeling component. For a complete analysis and in order to optimize the use of data, MD should also be treated in the multivariate setting prior to modeling and inference. Imputation of MD in the multivariate hydrological framework can have direct implications on the quality of the estimation. Indeed, the dependence between the series represents important additional information that can be included in the imputation process. The objective of the present paper is to highlight the importance of treating MD in multivariate hydrological frequency analysis by reviewing and applying multivariate imputation methods and by comparing univariate and multivariate imputation methods. An application is carried out for multiple flood attributes on three sites in order to evaluate the performance of the different methods based on the leave-one-out procedure. The results indicate that, the performance of imputation methods can be improved by adopting the multivariate setting, compared to mean substitution and interpolation methods, especially when using the copula-based approach.
Multivariate meta-analysis: potential and promise.
Jackson, Dan; Riley, Richard; White, Ian R
2011-09-10
The multivariate random effects model is a generalization of the standard univariate model. Multivariate meta-analysis is becoming more commonly used and the techniques and related computer software, although continually under development, are now in place. In order to raise awareness of the multivariate methods, and discuss their advantages and disadvantages, we organized a one day 'Multivariate meta-analysis' event at the Royal Statistical Society. In addition to disseminating the most recent developments, we also received an abundance of comments, concerns, insights, critiques and encouragement. This article provides a balanced account of the day's discourse. By giving others the opportunity to respond to our assessment, we hope to ensure that the various view points and opinions are aired before multivariate meta-analysis simply becomes another widely used de facto method without any proper consideration of it by the medical statistics community. We describe the areas of application that multivariate meta-analysis has found, the methods available, the difficulties typically encountered and the arguments for and against the multivariate methods, using four representative but contrasting examples. We conclude that the multivariate methods can be useful, and in particular can provide estimates with better statistical properties, but also that these benefits come at the price of making more assumptions which do not result in better inference in every case. Although there is evidence that multivariate meta-analysis has considerable potential, it must be even more carefully applied than its univariate counterpart in practice. Copyright © 2011 John Wiley & Sons, Ltd.
Multivariate meta-analysis: Potential and promise
Jackson, Dan; Riley, Richard; White, Ian R
2011-01-01
The multivariate random effects model is a generalization of the standard univariate model. Multivariate meta-analysis is becoming more commonly used and the techniques and related computer software, although continually under development, are now in place. In order to raise awareness of the multivariate methods, and discuss their advantages and disadvantages, we organized a one day ‘Multivariate meta-analysis’ event at the Royal Statistical Society. In addition to disseminating the most recent developments, we also received an abundance of comments, concerns, insights, critiques and encouragement. This article provides a balanced account of the day's discourse. By giving others the opportunity to respond to our assessment, we hope to ensure that the various view points and opinions are aired before multivariate meta-analysis simply becomes another widely used de facto method without any proper consideration of it by the medical statistics community. We describe the areas of application that multivariate meta-analysis has found, the methods available, the difficulties typically encountered and the arguments for and against the multivariate methods, using four representative but contrasting examples. We conclude that the multivariate methods can be useful, and in particular can provide estimates with better statistical properties, but also that these benefits come at the price of making more assumptions which do not result in better inference in every case. Although there is evidence that multivariate meta-analysis has considerable potential, it must be even more carefully applied than its univariate counterpart in practice. Copyright © 2011 John Wiley & Sons, Ltd. PMID:21268052
1983-10-01
sites should be collected and correlated to vegetational response through ordination or factor analysis techniques. 3. If site-specific methods are...specified number of samples is collected . If the 40 ."l ’ - - - .. -’-. - : -. .~ -, .4 .- . -.- , - ...... rb. . o* . -.% o - .- * .-.- v- . J...only, although the data collected were sufficient for determination of such parameters as density, cover, frequency, basal area, and importance value
Methods for presentation and display of multivariate data
NASA Technical Reports Server (NTRS)
Myers, R. H.
1981-01-01
Methods for the presentation and display of multivariate data are discussed with emphasis placed on the multivariate analysis of variance problems and the Hotelling T(2) solution in the two-sample case. The methods utilize the concepts of stepwise discrimination analysis and the computation of partial correlation coefficients.
Ogungbenro, Kayode; Aarons, Leon
2011-08-01
In the recent years, interest in the application of experimental design theory to population pharmacokinetic (PK) and pharmacodynamic (PD) experiments has increased. The aim is to improve the efficiency and the precision with which parameters are estimated during data analysis and sometimes to increase the power and reduce the sample size required for hypothesis testing. The population Fisher information matrix (PFIM) has been described for uniresponse and multiresponse population PK experiments for design evaluation and optimisation. Despite these developments and availability of tools for optimal design of population PK and PD experiments much of the effort has been focused on repeated continuous variable measurements with less work being done on repeated discrete type measurements. Discrete data arise mainly in PDs e.g. ordinal, nominal, dichotomous or count measurements. This paper implements expressions for the PFIM for repeated ordinal, dichotomous and count measurements based on analysis by a mixed-effects modelling technique. Three simulation studies were used to investigate the performance of the expressions. Example 1 is based on repeated dichotomous measurements, Example 2 is based on repeated count measurements and Example 3 is based on repeated ordinal measurements. Data simulated in MATLAB were analysed using NONMEM (Laplace method) and the glmmML package in R (Laplace and adaptive Gauss-Hermite quadrature methods). The results obtained for Examples 1 and 2 showed good agreement between the relative standard errors obtained using the PFIM and simulations. The results obtained for Example 3 showed the importance of sampling at the most informative time points. Implementation of these expressions will provide the opportunity for efficient design of population PD experiments that involve discrete type data through design evaluation and optimisation.
Zhe, Shandian; Xu, Zenglin; Qi, Yuan; Yu, Peng
2014-01-01
A key step for Alzheimer's disease (AD) study is to identify associations between genetic variations and intermediate phenotypes (e.g., brain structures). At the same time, it is crucial to develop a noninvasive means for AD diagnosis. Although these two tasks-association discovery and disease diagnosis-have been treated separately by a variety of approaches, they are tightly coupled due to their common biological basis. We hypothesize that the two tasks can potentially benefit each other by a joint analysis, because (i) the association study discovers correlated biomarkers from different data sources, which may help improve diagnosis accuracy, and (ii) the disease status may help identify disease-sensitive associations between genetic variations and MRI features. Based on this hypothesis, we present a new sparse Bayesian approach for joint association study and disease diagnosis. In this approach, common latent features are extracted from different data sources based on sparse projection matrices and used to predict multiple disease severity levels based on Gaussian process ordinal regression; in return, the disease status is used to guide the discovery of relationships between the data sources. The sparse projection matrices not only reveal the associations but also select groups of biomarkers related to AD. To learn the model from data, we develop an efficient variational expectation maximization algorithm. Simulation results demonstrate that our approach achieves higher accuracy in both predicting ordinal labels and discovering associations between data sources than alternative methods. We apply our approach to an imaging genetics dataset of AD. Our joint analysis approach not only identifies meaningful and interesting associations between genetic variations, brain structures, and AD status, but also achieves significantly higher accuracy for predicting ordinal AD stages than the competing methods.
Moore, Stephanie N; Hawley, Gregory D; Smith, Emily N; Mignemi, Nicholas A; Ihejirika, Rivka C; Yuasa, Masato; Cates, Justin M M; Liu, Xulei; Schoenecker, Jonathan G
2016-01-01
Soft tissue calcification, including both dystrophic calcification and heterotopic ossification, may occur following injury. These lesions have variable fates as they are either resorbed or persist. Persistent soft tissue calcification may result in chronic inflammation and/or loss of function of that soft tissue. The molecular mechanisms that result in the development and maturation of calcifications are uncertain. As a result, directed therapies that prevent or resorb soft tissue calcifications remain largely unsuccessful. Animal models of post-traumatic soft tissue calcification that allow for cost-effective, serial analysis of an individual animal over time are necessary to derive and test novel therapies. We have determined that a cardiotoxin-induced injury of the muscles in the posterior compartment of the lower extremity represents a useful model in which soft tissue calcification develops remote from adjacent bones, thereby allowing for serial analysis by plain radiography. The purpose of the study was to design and validate a method for quantifying soft tissue calcifications in mice longitudinally using plain radiographic techniques and an ordinal scoring system. Muscle injury was induced by injecting cardiotoxin into the posterior compartment of the lower extremity in mice susceptible to developing soft tissue calcification. Seven days following injury, radiographs were obtained under anesthesia. Multiple researchers applied methods designed to standardize post-image processing of digital radiographs (N = 4) and quantify soft tissue calcification (N = 6) in these images using an ordinal scoring system. Inter- and intra-observer agreement for both post-image processing and the scoring system used was assessed using weighted kappa statistics. Soft tissue calcification quantifications by the ordinal scale were compared to mineral volume measurements (threshold 450.7mgHA/cm3) determined by μCT. Finally, sample-size calculations necessary to discriminate between a 25%, 50%, 75%, and 100% difference in STiCSS score 7 days following burn/CTX induced muscle injury were determined. Precision analysis demonstrated substantial to good agreement for both post-image processing (κ = 0.73 to 0.90) and scoring (κ = 0.88 to 0.93), with low inter- and intra-observer variability. Additionally, there was a strong correlation in quantification of soft tissue calcification between the ordinal system and by mineral volume quantification by μCT (Spearman r = 0.83 to 0.89). The ordinal scoring system reliably quantified soft tissue calcification in a burn/CTX-induced soft tissue calcification model compared to non-injured controls (Mann-Whitney rank test: P = 0.0002, ***). Sample size calculations revealed that 6 mice per group would be required to detect a 50% difference in STiCSS score with a power of 0.8. Finally, the STiCSS was demonstrated to reliably quantify soft tissue calcification [dystrophic calcification and heterotopic ossification] by radiographic analysis, independent of the histopathological state of the mineralization. Radiographic analysis can discriminate muscle injury-induced soft tissue calcification from adjacent bone and follow its clinical course over time without requiring the sacrifice of the animal. While the STiCSS cannot identify the specific type of soft tissue calcification present, it is still a useful and valid method by which to quantify the degree of soft tissue calcification. This methodology allows for longitudinal measurements of soft tissue calcification in a single animal, which is relatively less expensive, less time-consuming, and exposes the animal to less radiation than in vivo μCT. Therefore, this high-throughput, longitudinal analytic method for quantifying soft tissue calcification is a viable alternative for the study of soft tissue calcification.
2013-01-01
Background The role of environmental factors in lumbar intervertebral disc degeneration (DD) in young adults is largely unknown. Therefore, we investigated whether body mass index (BMI), smoking, and physical activity are associated with lumbar DD among young adults. Methods The Oulu Back Study (OBS) is a subpopulation of the 1986 Northern Finland Birth Cohort (NFBC 1986) and it originally included 2,969 children. The OBS subjects received a postal questionnaire, and those who responded (N = 1,987) were invited to the physical examination. The participants (N = 874) were invited to lumbar MRI study. A total of 558 young adults (325 females and 233 males) underwent MRI that used a 1.5-T scanner at the mean age of 21. Each lumbar intervertebral disc was graded as normal (0), mildly (1), moderately (2), or severely (3) degenerated. We calculated a sum score of the lumbar DD, and analyzed the associations between environmental risk factors (smoking, physical activity and weight-related factors assessed at 16 and 19 years) and DD using ordinal logistic regression, the results being expressed as cumulative odds ratios (COR). All analyses were stratified by gender. Results Of the 558 subjects, 256 (46%) had no DD, 117 (21%) had sum score of one, 93 (17%) sum score of two, and 92 (17%) sum score of three or higher. In the multivariate ordinal logistic regression model, BMI at 16 years (highest vs. lowest quartile) was associated with DD sum score among males (COR 2.35; 95% CI 1.19-4.65) but not among females (COR 1.29; 95% CI 0.72-2.32). Smoking of at least four pack-years was associated with DD among males, but not among females (COR 2.41; 95% CI 0.99-5.86 and 1.59; 95% 0.67-3.76, respectively). Self-reported physical activity was not associated with DD. Conclusions High BMI at 16 years was associated with lumbar DD at 21 years among young males but not among females. High pack-years of smoking showed a comparable association in males, while physical activity had no association with DD in either gender. These results suggest that environmental factors are associated with DD among young males. PMID:23497297
Ordinal Position, Sex of Sibling, Sex, and Personal Preferences in a Group of Eighteen Year Olds
ERIC Educational Resources Information Center
Oberlander, Mark I.; And Others
1970-01-01
Investigates three hypotheses derived from previous research, that different ordinal position groups manifest differential personal preference patterns, as measured by the Kuder Preference Record. (Author)
Ordinal regression models to describe tourist satisfaction with Sintra's world heritage
NASA Astrophysics Data System (ADS)
Mouriño, Helena
2013-10-01
In Tourism Research, ordinal regression models are becoming a very powerful tool in modelling the relationship between an ordinal response variable and a set of explanatory variables. In August and September 2010, we conducted a pioneering Tourist Survey in Sintra, Portugal. The data were obtained by face-to-face interviews at the entrances of the Palaces and Parks of Sintra. The work developed in this paper focus on two main points: tourists' perception of the entrance fees; overall level of satisfaction with this heritage site. For attaining these goals, ordinal regression models were developed. We concluded that tourist's nationality was the only significant variable to describe the perception of the admission fees. Also, Sintra's image among tourists depends not only on their nationality, but also on previous knowledge about Sintra's World Heritage status.
Modeling Personalized Email Prioritization: Classification-based and Regression-based Approaches
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoo S.; Yang, Y.; Carbonell, J.
2011-10-24
Email overload, even after spam filtering, presents a serious productivity challenge for busy professionals and executives. One solution is automated prioritization of incoming emails to ensure the most important are read and processed quickly, while others are processed later as/if time permits in declining priority levels. This paper presents a study of machine learning approaches to email prioritization into discrete levels, comparing ordinal regression versus classier cascades. Given the ordinal nature of discrete email priority levels, SVM ordinal regression would be expected to perform well, but surprisingly a cascade of SVM classifiers significantly outperforms ordinal regression for email prioritization. Inmore » contrast, SVM regression performs well -- better than classifiers -- on selected UCI data sets. This unexpected performance inversion is analyzed and results are presented, providing core functionality for email prioritization systems.« less
Kramer, J A; Hill, K T; Cohen, L B
1975-03-01
To investigate Piaget's theory of object concept development, a series of 6 tasks was administered in a combined longitudinal/cross-sectional design incorporating a number of methodological controls. The tasks spanned the entire sensorimotor period and included single versus sequential displacements combined with visible or invisible hidings. 36 infants from 5 to 32 months of age at initial testing were drawn equally from day-care and home settings. All infants received the 6 tasks during each of 3 testing sessions over a 6-month period. Clear evidence was obtained for task ordinality as proposed by Piaget, with ordinality coefficients ranging from .71 to .82 for the 3 testing sessions. Performance changes across the 3 sessions were also ordinal in 80% of the cases. Expected age, task, and session effects and accompanying interactions were also obtained.
Multiple Ordinal Regression by Maximizing the Sum of Margins
Hamsici, Onur C.; Martinez, Aleix M.
2016-01-01
Human preferences are usually measured using ordinal variables. A system whose goal is to estimate the preferences of humans and their underlying decision mechanisms requires to learn the ordering of any given sample set. We consider the solution of this ordinal regression problem using a Support Vector Machine algorithm. Specifically, the goal is to learn a set of classifiers with common direction vectors and different biases correctly separating the ordered classes. Current algorithms are either required to solve a quadratic optimization problem, which is computationally expensive, or are based on maximizing the minimum margin (i.e., a fixed margin strategy) between a set of hyperplanes, which biases the solution to the closest margin. Another drawback of these strategies is that they are limited to order the classes using a single ranking variable (e.g., perceived length). In this paper, we define a multiple ordinal regression algorithm based on maximizing the sum of the margins between every consecutive class with respect to one or more rankings (e.g., perceived length and weight). We provide derivations of an efficient, easy-to-implement iterative solution using a Sequential Minimal Optimization procedure. We demonstrate the accuracy of our solutions in several datasets. In addition, we provide a key application of our algorithms in estimating human subjects’ ordinal classification of attribute associations to object categories. We show that these ordinal associations perform better than the binary one typically employed in the literature. PMID:26529784
Lanthanide co-ordination frameworks: Opportunities and diversity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hill, Robert J.; Long, De-Liang; Hubberstey, Peter
2005-08-15
Significant successes have been made over recent years in preparing co-ordination framework polymers that show macroscopic material properties, but in the vast majority of cases this has been achieved with d-block metal-based systems. Lanthanide co-ordination frameworks also offer attractive properties in terms of their potential applications as luminescent, non-linear optical and porous materials. However, lanthanide-based systems have been far less studied to date than their d-block counterparts. One possible reason for this is that the co-ordination spheres of lanthanide cations are more difficult to control and, in the absence of design strategies for lanthanide co-ordination frameworks, it is significantly moremore » difficult to target materials with specific properties. However, this article highlights some of the exciting possibilities that have emerged from the earliest investigations in this field with new topological families of compounds being discovered from relatively simple framework components, including unusual eight, seven and five-connected framework systems. Our own research, as well as others, is leading to a much greater appreciation of the factors that control framework formation and the resultant observed topologies of these polymers. As this understanding develops targeting particular framework types will become more straightforward and the development of designed polyfunctional materials more accessible. Thus, it can be seen that lanthanide co-ordination frameworks have the potential to open up previously unexplored directions for materials chemistry. This article focuses on the underlying concepts for the construction of these enticing and potentially highly important materials.« less
An ordinal classification approach for CTG categorization.
Georgoulas, George; Karvelis, Petros; Gavrilis, Dimitris; Stylios, Chrysostomos D; Nikolakopoulos, George
2017-07-01
Evaluation of cardiotocogram (CTG) is a standard approach employed during pregnancy and delivery. But, its interpretation requires high level expertise to decide whether the recording is Normal, Suspicious or Pathological. Therefore, a number of attempts have been carried out over the past three decades for development automated sophisticated systems. These systems are usually (multiclass) classification systems that assign a category to the respective CTG. However most of these systems usually do not take into consideration the natural ordering of the categories associated with CTG recordings. In this work, an algorithm that explicitly takes into consideration the ordering of CTG categories, based on binary decomposition method, is investigated. Achieved results, using as a base classifier the C4.5 decision tree classifier, prove that the ordinal classification approach is marginally better than the traditional multiclass classification approach, which utilizes the standard C4.5 algorithm for several performance criteria.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gulshani, P., E-mail: matlap@bell.net
We derive a microscopic version of the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for collective rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude. The nuclear Schrodinger equation is canonically transformed to collective co-ordinates, which is then linearized using a constrained variational method. The associated constraints are imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For harmonic oscillator mean-field potentials, these equations are solved in closed forms for excitation energy,more » cut-off angular momentum, and other nuclear properties for the ground-state rotational band in some deformed nuclei. The results are compared with measured data.« less
Li, Siying; Koch, Gary G; Preisser, John S; Lam, Diana; Sanchez-Kam, Matilde
2017-01-01
Dichotomous endpoints in clinical trials have only two possible outcomes, either directly or via categorization of an ordinal or continuous observation. It is common to have missing data for one or more visits during a multi-visit study. This paper presents a closed form method for sensitivity analysis of a randomized multi-visit clinical trial that possibly has missing not at random (MNAR) dichotomous data. Counts of missing data are redistributed to the favorable and unfavorable outcomes mathematically to address possibly informative missing data. Adjusted proportion estimates and their closed form covariance matrix estimates are provided. Treatment comparisons over time are addressed with Mantel-Haenszel adjustment for a stratification factor and/or randomization-based adjustment for baseline covariables. The application of such sensitivity analyses is illustrated with an example. An appendix outlines an extension of the methodology to ordinal endpoints.
NASA Technical Reports Server (NTRS)
Jensen, K. A.; Ripoll, J.-F.; Wray, A. A.; Joseph, D.; ElHafi, M.
2004-01-01
Five computational methods for solution of the radiative transfer equation in an absorbing-emitting and non-scattering gray medium were compared on a 2 m JP-8 pool fire. The temperature and absorption coefficient fields were taken from a synthetic fire due to the lack of a complete set of experimental data for fires of this size. These quantities were generated by a code that has been shown to agree well with the limited quantity of relevant data in the literature. Reference solutions to the governing equation were determined using the Monte Carlo method and a ray tracing scheme with high angular resolution. Solutions using the discrete transfer method, the discrete ordinate method (DOM) with both S(sub 4) and LC(sub 11) quadratures, and moment model using the M(sub 1) closure were compared to the reference solutions in both isotropic and anisotropic regions of the computational domain. DOM LC(sub 11) is shown to be the more accurate than the commonly used S(sub 4) quadrature technique, especially in anisotropic regions of the fire domain. This represents the first study where the M(sub 1) method was applied to a combustion problem occurring in a complex three-dimensional geometry. The M(sub 1) results agree well with other solution techniques, which is encouraging for future applications to similar problems since it is computationally the least expensive solution technique. Moreover, M(sub 1) results are comparable to DOM S(sub 4).
NASA Astrophysics Data System (ADS)
Bailly, J. S.; Dartevelle, M.; Delenne, C.; Rousseau, A.
2017-12-01
Floodplain and major river bed topography govern many river biophysical processes during floods. Despite the grow of direct topographic measurements from LiDARS on riverine systems, it still room to develop methods for large (e.g. deltas) or very local (e.g. ponds) riverine systems that take advantage of information coming from simple SAR or optical image processing on floodplain, resulting from waterbodies delineation during flood up or down, and producing ordered coutour lines. The next challenge is thus to exploit such data in order to estimate continuous topography on the floodplain combining heterogeneous data: a topographic points dataset and a located but unknown and ordered contourline dataset. This article is comparing two methods designed to estimate continuous topography on the floodplain mixing ordinal coutour lines and continuous topographic points. For both methods a first estimation step is to value each contourline with elevation and a second step is next to estimate the continuous field from both topographic points and valued contourlines. The first proposed method is a stochastic method starting from multigaussian random-fields and conditional simualtion. The second is a deterministic method based on radial spline fonction for thin layers used for approximated bivariate surface construction. Results are first shown and discussed from a set of synoptic case studies presenting various topographic points density and topographic smoothness. Next, results are shown and discuss on an actual case study in the Montagua laguna, located in the north of Valparaiso, Chile.
NASA Astrophysics Data System (ADS)
Brown, T. G.; Lespez, L.; Sear, D. A.; Houben, P.; Klimek, K.
2016-12-01
Floodplain and major river bed topography govern many river biophysical processes during floods. Despite the grow of direct topographic measurements from LiDARS on riverine systems, it still room to develop methods for large (e.g. deltas) or very local (e.g. ponds) riverine systems that take advantage of information coming from simple SAR or optical image processing on floodplain, resulting from waterbodies delineation during flood up or down, and producing ordered coutour lines. The next challenge is thus to exploit such data in order to estimate continuous topography on the floodplain combining heterogeneous data: a topographic points dataset and a located but unknown and ordered contourline dataset. This article is comparing two methods designed to estimate continuous topography on the floodplain mixing ordinal coutour lines and continuous topographic points. For both methods a first estimation step is to value each contourline with elevation and a second step is next to estimate the continuous field from both topographic points and valued contourlines. The first proposed method is a stochastic method starting from multigaussian random-fields and conditional simualtion. The second is a deterministic method based on radial spline fonction for thin layers used for approximated bivariate surface construction. Results are first shown and discussed from a set of synoptic case studies presenting various topographic points density and topographic smoothness. Next, results are shown and discuss on an actual case study in the Montagua laguna, located in the north of Valparaiso, Chile.
Relationship of stigma and depression among newly HIV-diagnosed Chinese men who have sex with men
Tao, Jun; Wang, Lijuan; Kipp, Aaron M.; Qian, Han-Zhu; Yin, Lu; Ruan, Yuhua; Shao, Yiming; Lu, Hongyan; Vermund, Sten H.
2016-01-01
Little is known about the relationship between HIV stigma and depression among newly diagnosed HIV-infected men who have sex with men (MSM). We measured HIV-related stigma and current depression using standard scales among 367 Chinese MSM who had been diagnosed very recently with HIV infection, analyzing key associations with multivariable ordinal logistic regression. Current depression prevalence was 36%. Median scores for felt, vicarious, and internalized stigma were 17, 2, and 5, respectively, each on a 0–30 scale. A one-point increase in the total stigma score was associated with a 4% increase in the odds of current depression (adjusted odds ratio [aOR] = 1.04, 95% confidence interval [CI] = 1.03–1.05). Internalized stigma had the strongest association with depression (aOR = 1.09, 95% CI = 1.07–1.12). Effective interventions to address coping with HIV-related stigma immediately following HIV-diagnosis might help reduce depression, improve long-term mental health, and improve engagement in their care. PMID:27376900
Swanson, Mark W; Bodner, Eric; Sawyer, Patricia; Allman, Richard
2013-01-01
Little is known about the affect of reduced vision on physical activity in older adults. This study evaluates the association of visual acuity level, self-reported vision and ocular disease conditions with leisure-time physical activity and calculated caloric expenditure. A cross sectional study of 911 subjects 65 yr and older from the University of Alabama at Birmingham Study of Aging (SOA) cohort was conducted evaluating the association of vision-related variables to weekly kilocalorie expenditure calculated from the 17-item Leisure Time Physical Activity Questionnaire. Ordinal logistic regression was used to evaluate possible associations controlling for potential confounders. In multivariate analyses, each lower step in visual acuity category below 20/50 was significantly associated with reduced odds of having a higher level of physical activity OR 0.81, 95% CI 0.67, 0.97. Reduced visual acuity appears to be independently associated with lower levels of physical activity among community-dwelling adults. PMID:21945888
Bartle, Carly J; Goozée, Justine V; Scott, Dion; Murdoch, Bruce E; Kuruvilla, Mili
2006-05-01
To investigate the spatio-timing aspects of tongue-jaw co-ordination during speech in individuals with traumatic brain injury (TBI). It was hypothesized that both timing and spatial co-ordination would be affected by TBI. A group comparison design wherein Mann-Whitney U-tests were used to compare non-neurologically impaired individuals with individuals with TBI. Nine non-neurologically impaired adults and nine adults with TBI were involved in the study. Electromagnetic articulography (EMA) was used to track tongue and jaw movement during /t/ and /k/, embedded in sentence and syllable stimuli. Analysis of group data did not reveal a significant difference in spatio-timing tongue-jaw co-ordination between the control group and TBI group. On an individual basis, a proportion of individuals with TBI differed from non-neurologically impaired participants with regard to articulatory order and percentage of jaw contribution to /t/. EMA assessment results supported perceptual data; those adults who presented with severe articulatory disturbances exhibited the most deviant spatio-timing tongue-jaw co-ordination patterns. This finding could provide a new and specific direction for treatment, directed at combined movement patterns.
Glantz, S A; Wilson-Loots, R
2003-12-01
Because it is widely played, claims that smoking restrictions will adversely affect bingo games is used as an argument against these policies. We used publicly available data from Massachusetts to assess the impact of 100% smoke-free ordinances on profits from bingo and other gambling sponsored by charitable organisations between 1985 and 2001. We conducted two analyses: (1) a general linear model implementation of a time series analysis with net profits (adjusted to 2001 dollars) as the dependent variable, and community (as a fixed effect), year, lagged net profits, and the length of time the ordinance had been in force as the independent variables; (2) multiple linear regression of total state profits against time, lagged profits, and the percentage of the entire state population in communities that allow charitable gaming but prohibit smoking. The general linear model analysis of data from individual communities showed that, while adjusted profits fell over time, this effect was not related to the presence of an ordinance. The analysis in terms of the fraction of the population living in communities with ordinances yielded the same result. Policymakers can implement smoke-free policies without concern that these policies will affect charitable gaming.
Bridges, John F. P.; Slawik, Lara; Schmeding, Annette; Reimer, Jens; Naber, Dieter; Kuhnigk, Olaf
2011-01-01
Abstract Background While much discussion has been placed on the problem of poor compliance in the treatment of schizophrenia, there has been little discussion on the concordance between patients and psychiatrists, an important contributing factor to patient‐centred care. Objective To estimate the concordance between patients’ and psychiatrists’ (ordinal and cardinal) valuations of multiple goals for schizophrenia treatment and to illustrate the utility of the self‐explicated method in valuing a large number of treatment goals. Design Twenty treatment goals were identified during focus groups and literature review and were presented to patients and psychiatrists during structured interviews. Respondents were asked to rank the multiple treatment goals and rate them on a 5‐point Likert scale. Three scores were calculated based on the ranking (1–20), rating (Likert scale) (1–5) and a self‐explicated method estimated as the product of rating and ranking score (1–100). Concordance was tested using Spearman’s rho for overall ordinal rankings and via anova and F‐test for the cardinal values assigned to a specific treatment goal. Participants A total of 105 outpatients diagnosed with schizophrenia and 160 psychiatrists in Germany. Results Patient and psychiatrist values were concordant when the ordinal properties of their valuations were assessed by rating (ρ = 0.63; P = 0.002), ranking (ρ = 0.51; P = 0.02) and self‐explicated methods (ρ = 0.54; P = 0.01). Significant discordances were found when comparing the cardinal value placed on any given treatment goal using all three approaches, but the self‐explicated method produced a more discerning statistic. Relative to patients, psychiatrists significantly (P < 0.05) overvalued reduced lack of emotion, improved sexual pleasure and improved communication while undervaluing reuptake of activities of daily living, improved satisfaction and recovered capacity for work. Conclusions While there is an overall concordance between patients’ and psychiatrists’ valuation, significantly different valuations on specific goals can be identified. Here, psychiatrists tend to focus on ‘textbook’ outcomes, while patients are more concerned with functioning and living a normal life. This study also demonstrates the importance of comparing the concordance in treatment goals and the importance of preference‐based methods, such as the self‐explicated method, in the study of concordance. PMID:21668795
Lee, Dong Hoon; Kim, Jin Hwi; Mendoza, Joseph A; Lee, Chang Hee; Kang, Joo-Hyon
2016-05-01
While identification of critical pollutant sources is the key initial step for cost-effective runoff management, it is challenging due to the highly uncertain nature of runoff pollution, especially during a storm event. To identify critical sources and their quantitative contributions to runoff pollution (especially focusing on phosphorous), two ordination methods were used in this study: principal component analysis (PCA) and positive matrix factorization (PMF). For the ordination analyses, we used runoff quality data for 14 storm events, including data for phosphorus, 11 heavy metal species, and eight ionic species measured at the outlets of subcatchments with different land use compositions in a mixed land use watershed. Five factors as sources of runoff pollutants were identified by PCA: agrochemicals, groundwater, native soils, domestic sewage, and urban sources (building materials and automotive activities). PMF identified similar factors to those identified by PCA, with more detailed source mechanisms for groundwater (i.e., nitrate leaching and cation exchange) and urban sources (vehicle components/motor oils/building materials and vehicle exhausts), confirming the sources identified by PCA. PMF was further used to quantify contributions of the identified sources to the water quality. Based on the results, agrochemicals and automotive activities were the two dominant and ubiquitous phosphorus sources (39-61 and 16-47 %, respectively) in the study area, regardless of land use types.
2011-01-01
Background Logistic random effects models are a popular tool to analyze multilevel also called hierarchical data with a binary or ordinal outcome. Here, we aim to compare different statistical software implementations of these models. Methods We used individual patient data from 8509 patients in 231 centers with moderate and severe Traumatic Brain Injury (TBI) enrolled in eight Randomized Controlled Trials (RCTs) and three observational studies. We fitted logistic random effects regression models with the 5-point Glasgow Outcome Scale (GOS) as outcome, both dichotomized as well as ordinal, with center and/or trial as random effects, and as covariates age, motor score, pupil reactivity or trial. We then compared the implementations of frequentist and Bayesian methods to estimate the fixed and random effects. Frequentist approaches included R (lme4), Stata (GLLAMM), SAS (GLIMMIX and NLMIXED), MLwiN ([R]IGLS) and MIXOR, Bayesian approaches included WinBUGS, MLwiN (MCMC), R package MCMCglmm and SAS experimental procedure MCMC. Three data sets (the full data set and two sub-datasets) were analysed using basically two logistic random effects models with either one random effect for the center or two random effects for center and trial. For the ordinal outcome in the full data set also a proportional odds model with a random center effect was fitted. Results The packages gave similar parameter estimates for both the fixed and random effects and for the binary (and ordinal) models for the main study and when based on a relatively large number of level-1 (patient level) data compared to the number of level-2 (hospital level) data. However, when based on relatively sparse data set, i.e. when the numbers of level-1 and level-2 data units were about the same, the frequentist and Bayesian approaches showed somewhat different results. The software implementations differ considerably in flexibility, computation time, and usability. There are also differences in the availability of additional tools for model evaluation, such as diagnostic plots. The experimental SAS (version 9.2) procedure MCMC appeared to be inefficient. Conclusions On relatively large data sets, the different software implementations of logistic random effects regression models produced similar results. Thus, for a large data set there seems to be no explicit preference (of course if there is no preference from a philosophical point of view) for either a frequentist or Bayesian approach (if based on vague priors). The choice for a particular implementation may largely depend on the desired flexibility, and the usability of the package. For small data sets the random effects variances are difficult to estimate. In the frequentist approaches the MLE of this variance was often estimated zero with a standard error that is either zero or could not be determined, while for Bayesian methods the estimates could depend on the chosen "non-informative" prior of the variance parameter. The starting value for the variance parameter may be also critical for the convergence of the Markov chain. PMID:21605357
Modeling Working Memory Tasks on the Item Level
ERIC Educational Resources Information Center
Luo, Dasen; Chen, Guopeng; Zen, Fanlin; Murray, Bronwyn
2010-01-01
Item responses to Digit Span and Letter-Number Sequencing were analyzed to develop a better-refined model of the two working memory tasks using the finite mixture (FM) modeling method. Models with ordinal latent traits were found to better account for the independent sources of the variability in the tasks than those with continuous traits, and…
ERIC Educational Resources Information Center
Gray, Colette
2009-01-01
This paper reports the experiences of special education needs co-ordinators (SENCOs) on the inclusion of pupils with a visual impairment (VI) in mainstream schools in Northern Ireland. A mixed method approach (postal questionnaire survey (n=113) and interviews (n=6)) was utilised to triangulate the findings. The results indicate an inverse…
Proximity Analysis and the Structure of Organization in Free Recall.
ERIC Educational Resources Information Center
Friendly, Michael L.
A method for assessing the structure of organization was developed on the basis of the ordinal separation, or proximity, between pairs ot items in recall protocols over a series of trials. The proximity measure is based on the assumption, common to all indices of organization, that items which are coded together in subjective memory units will…
TH-AB-BRA-09: Stability Analysis of a Novel Dose Calculation Algorithm for MRI Guided Radiotherapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zelyak, O; Fallone, B; Cross Cancer Institute, Edmonton, AB
2016-06-15
Purpose: To determine the iterative deterministic solution stability of the Linear Boltzmann Transport Equation (LBTE) in the presence of magnetic fields. Methods: The LBTE with magnetic fields under investigation is derived using a discrete ordinates approach. The stability analysis is performed using analytical and numerical methods. Analytically, the spectral Fourier analysis is used to obtain the convergence rate of the source iteration procedures based on finding the largest eigenvalue of the iterative operator. This eigenvalue is a function of relevant physical parameters, such as magnetic field strength and material properties, and provides essential information about the domain of applicability requiredmore » for clinically optimal parameter selection and maximum speed of convergence. The analytical results are reinforced by numerical simulations performed using the same discrete ordinates method in angle, and a discontinuous finite element spatial approach. Results: The spectral radius for the source iteration technique of the time independent transport equation with isotropic and anisotropic scattering centers inside infinite 3D medium is equal to the ratio of differential and total cross sections. The result is confirmed numerically by solving LBTE and is in full agreement with previously published results. The addition of magnetic field reveals that the convergence becomes dependent on the strength of magnetic field, the energy group discretization, and the order of anisotropic expansion. Conclusion: The source iteration technique for solving the LBTE with magnetic fields with the discrete ordinates method leads to divergent solutions in the limiting cases of small energy discretizations and high magnetic field strengths. Future investigations into non-stationary Krylov subspace techniques as an iterative solver will be performed as this has been shown to produce greater stability than source iteration. Furthermore, a stability analysis of a discontinuous finite element space-angle approach (which has been shown to provide the greatest stability) will also be investigated. Dr. B Gino Fallone is a co-founder and CEO of MagnetTx Oncology Solutions (under discussions to license Alberta bi-planar linac MR for commercialization)« less
The effect of small variations in profile of airfoils
NASA Technical Reports Server (NTRS)
Ward, Kenneth E
1931-01-01
This report deals with the effect of small variations in ordinates specified by different laboratories for the airfoil section. This study was made in connection with a more general investigation of the effect of small irregularities of the airfoil surface on the aerodynamic characteristics of an airfoil. These tests show that small changes in airfoil contours, resulting from variations in the specified ordinates, have a sufficiently large effect upon the airfoil characteristics to justify the taking of great care in the specification of ordinates for the construction of models.
Effective communication and teamwork promotes patient safety.
Gluyas, Heather
2015-08-05
Teamwork requires co-operation, co-ordination and communication between members of a team to achieve desired outcomes. In industries with a high degree of risk, such as health care, effective teamwork has been shown to achieve team goals successfully and efficiently, with fewer errors. This article introduces behaviours that support communication, co-operation and co-ordination in teams. The central role of communication in enabling co-operation and co-ordination is explored. A human factors perspective is used to examine tools to improve communication and identify barriers to effective team communication in health care.
Guidelines and incentives for conservation development in local land-use regulations.
Reed, Sarah E; Hilty, Jodi A; Theobald, David M
2014-02-01
Effective conservation of biological diversity on private lands will require changes in land-use policy and development practice. Conservation development (CD) is an alternative form of residential development in which homes are built on smaller lots and clustered together and the remainder of the property is permanently protected for conservation purposes. We assessed the degree to which CD is permitted and encouraged by local land-use regulations in 414 counties in the western United States. Thirty-two percent of local planning jurisdictions have adopted CD ordinances, mostly within the past 10 years. CD ordinances were adopted in counties with human population densities that were 3.0 times greater and in counties with 2.5 times more land use at urban, suburban, and exurban densities than counties without CD ordinances. Despite strong economic incentives for CD (e.g., density bonuses, which allow for a mean of 66% more homes to be built per subdivision area), several issues may limit the effectiveness of CD for biological diversity conservation. Although most CD ordinances required a greater proportion of the site area be protected than in a typical residential development, just 13% (n = 17) of the ordinances required an ecological site analysis to identify and map features that should be protected. Few CD ordinances provided guidelines regarding the design and configuration of the protected lands, including specifying a minimum size for protected land parcels or encouraging contiguity with other protected lands within or near to the site. Eight percent (n =11) of CD ordinances encouraged consultation with a biological expert or compliance with a conservation plan. We recommend that conservation scientists help to improve the effectiveness of CD by educating planning staff and government officials regarding biological diversity conservation, volunteering for their local planning boards, or consulting on development reviews. © 2013 Society for Conservation Biology.
Sharafi, Zahra
2017-01-01
Background The purpose of this study was to evaluate the effectiveness of two methods of detecting differential item functioning (DIF) in the presence of multilevel data and polytomously scored items. The assessment of DIF with multilevel data (e.g., patients nested within hospitals, hospitals nested within districts) from large-scale assessment programs has received considerable attention but very few studies evaluated the effect of hierarchical structure of data on DIF detection for polytomously scored items. Methods The ordinal logistic regression (OLR) and hierarchical ordinal logistic regression (HOLR) were utilized to assess DIF in simulated and real multilevel polytomous data. Six factors (DIF magnitude, grouping variable, intraclass correlation coefficient, number of clusters, number of participants per cluster, and item discrimination parameter) with a fully crossed design were considered in the simulation study. Furthermore, data of Pediatric Quality of Life Inventory™ (PedsQL™) 4.0 collected from 576 healthy school children were analyzed. Results Overall, results indicate that both methods performed equivalently in terms of controlling Type I error and detection power rates. Conclusions The current study showed negligible difference between OLR and HOLR in detecting DIF with polytomously scored items in a hierarchical structure. Implications and considerations while analyzing real data were also discussed. PMID:29312463
Mandel, Micha; Gauthier, Susan A; Guttmann, Charles R G; Weiner, Howard L; Betensky, Rebecca A
2007-12-01
The expanded disability status scale (EDSS) is an ordinal score that measures progression in multiple sclerosis (MS). Progression is defined as reaching EDSS of a certain level (absolute progression) or increasing of one point of EDSS (relative progression). Survival methods for time to progression are not adequate for such data since they do not exploit the EDSS level at the end of follow-up. Instead, we suggest a Markov transitional model applicable for repeated categorical or ordinal data. This approach enables derivation of covariate-specific survival curves, obtained after estimation of the regression coefficients and manipulations of the resulting transition matrix. Large sample theory and resampling methods are employed to derive pointwise confidence intervals, which perform well in simulation. Methods for generating survival curves for time to EDSS of a certain level, time to increase of EDSS of at least one point, and time to two consecutive visits with EDSS greater than three are described explicitly. The regression models described are easily implemented using standard software packages. Survival curves are obtained from the regression results using packages that support simple matrix calculation. We present and demonstrate our method on data collected at the Partners MS center in Boston, MA. We apply our approach to progression defined by time to two consecutive visits with EDSS greater than three, and calculate crude (without covariates) and covariate-specific curves.
DIE BEWERTUNG VON OZONREAKTOREN
Evaluation of Ozone Reactors
The use of lake water as drinking water resource involves a multistage treatment procedure. Food-related laws and regulations, in particular the food ordinance and the hygiene ordinance, require the identification and assessment of health risks, ...
47 CFR 73.186 - Establishment of effective field at one kilometer.
Code of Federal Regulations, 2010 CFR
2010-10-01
... coordinate paper, plot field strengths as ordinate and distance as abscissa. (ii) Using semi-log coordinate paper, plot field strength times distance as ordinate on the log scale and distance as abscissa on the...
Multivariate assessment of event-related potentials with the t-CWT method.
Bostanov, Vladimir
2015-11-05
Event-related brain potentials (ERPs) are usually assessed with univariate statistical tests although they are essentially multivariate objects. Brain-computer interface applications are a notable exception to this practice, because they are based on multivariate classification of single-trial ERPs. Multivariate ERP assessment can be facilitated by feature extraction methods. One such method is t-CWT, a mathematical-statistical algorithm based on the continuous wavelet transform (CWT) and Student's t-test. This article begins with a geometric primer on some basic concepts of multivariate statistics as applied to ERP assessment in general and to the t-CWT method in particular. Further, it presents for the first time a detailed, step-by-step, formal mathematical description of the t-CWT algorithm. A new multivariate outlier rejection procedure based on principal component analysis in the frequency domain is presented as an important pre-processing step. The MATLAB and GNU Octave implementation of t-CWT is also made publicly available for the first time as free and open source code. The method is demonstrated on some example ERP data obtained in a passive oddball paradigm. Finally, some conceptually novel applications of the multivariate approach in general and of the t-CWT method in particular are suggested and discussed. Hopefully, the publication of both the t-CWT source code and its underlying mathematical algorithm along with a didactic geometric introduction to some basic concepts of multivariate statistics would make t-CWT more accessible to both users and developers in the field of neuroscience research.
Psychosocial risk exposures and labour management practices. An exploratory approach.
Llorens, Clara; Alós, Ramon; Cano, Ernest; Font, Ariadna; Jódar, Pere; López, Vicente; Navarro, Albert; Sánchez, Amat; Utzet, Mireia; Moncada, Salvador
2010-02-01
The purpose was to explore the relationship between psychosocial risk exposures and labour management practices (LMP), as indicators of work organization and pertinent features for primary preventive intervention. Cross-sectional study of a representative sample of salaried working population in Spain (n = 7,612). Information was obtained in 2004-2005 using a standardized questionnaire administered through personal interviews at the household. Questions on working conditions were used to establish LMP indicators and the psychosocial exposures data were obtained on the basis of the Copenhagen Psychosocial Questionnaire (COPSOQ) I (ISTAS21). A multivariate description was performed through multiple correspondence analysis, and associations between LMPs and psychosocial exposures were assessed by ordinal logistic analysis adjusting for age and sex. Correspondence analysis showed a good-bad coherent pattern regarding both psychosocial dimension and LMPs, though several LMPs categories were placed in the centre. Among the 14 possible associations of each psychosocial scale with LMP variables, several scales showed significant associations with more than eight LMP variables. Most relevant results referred to the LMP variable ''Consultative and delegative participation in methods''. In line with previous research, psychosocial exposures were associated with LMP. LMP may constitute a step on a pathway from work organization to health. Our exploratory work suggested that good psychosocial exposures were related to participatory working methods, being hired with a permanent labour contract, not being made to feel easily replaceable, having superiors with non-authoritarian and non-aggressive manners, not being threatened with dismissal, upward functional mobility, being paid according to the number of working hours and occupation, working between 31 and 40 hours per week and in regular morning shifts. Hence, the more these features became part of LMP in the workplace, the better the psychosocial work environment would be.
Multivariate Boosting for Integrative Analysis of High-Dimensional Cancer Genomic Data
Xiong, Lie; Kuan, Pei-Fen; Tian, Jianan; Keles, Sunduz; Wang, Sijian
2015-01-01
In this paper, we propose a novel multivariate component-wise boosting method for fitting multivariate response regression models under the high-dimension, low sample size setting. Our method is motivated by modeling the association among different biological molecules based on multiple types of high-dimensional genomic data. Particularly, we are interested in two applications: studying the influence of DNA copy number alterations on RNA transcript levels and investigating the association between DNA methylation and gene expression. For this purpose, we model the dependence of the RNA expression levels on DNA copy number alterations and the dependence of gene expression on DNA methylation through multivariate regression models and utilize boosting-type method to handle the high dimensionality as well as model the possible nonlinear associations. The performance of the proposed method is demonstrated through simulation studies. Finally, our multivariate boosting method is applied to two breast cancer studies. PMID:26609213
Jusufovic, Mirza; Sandset, Else Charlotte; Bath, Philip M; Berge, Eivind
2016-08-01
Early blood pressure-lowering treatment appears to be beneficial in patients with acute intracerebral haemorrhage and potentially in ischaemic stroke. We used a new method for analysis of vascular events in the Scandinavian Candesartan Acute Stroke Trial to see if the effect was dependent on the timing of treatment. Scandinavian Candesartan Acute Stroke Trial was a randomized controlled and placebo-controlled trial of candesartan within 30 h of ischaemic or haemorrhagic stroke. Of 2029 patients, 231 (11.4%) had a vascular event (vascular death, nonfatal stroke or nonfatal myocardial infarction) during the first 6 months. The modified Rankin Scale (mRS) score following a vascular event was used to categorize vascular events in order of severity: no event (n = 1798), minor (mRS 0-2, n = 59), moderately severe (mRS 3-4, n = 57) and major event (mRS 5-6, n = 115). We used ordinal logistic regression for analysis and adjusted for predefined prognostic variables. Candesartan had no overall effect on vascular events (adjusted common odds ratio 1.11, 95% confidence interval 0.84-1.47, P = 0.48), and the effects were the same in ischaemic and haemorrhagic stroke. Among the patients treated within 6 h, the adjusted common odds ratio for vascular events was 0.37, 95% confidence interval 0.16-0.84, P = 0.02, and there was no heterogeneity of effect between ischaemic and haemorrhagic strokes. Ordinal analysis of vascular events showed no overall effect of candesartan in the subacute phase of stroke. The effect of treatment given within 6 h of stroke onset appears promising, and will be addressed in ongoing trials. Ordinal analysis of vascular events is feasible and can be used in future trials.
Implementation of a Legionella Ordinance for Multifamily Housing, Garland, Texas
Whitney, Ellen A.; Blake, Sarah
2017-01-01
Context: The incidence of legionellosis has sharply increased in the United States as a result of contaminated water systems. Jurisdictions across the country are considering whether to develop and implement regulations to protect individuals against Legionnaires' disease with its associated high morbidity and mortality. Objective: This article sheds light on the implementation and effectiveness of a 2005 citywide Legionella testing mandate of multifamily housing cooling towers in Garland, Texas. This ordinance has been in place for more than 10 years and represents the first of its kind in the United States to mandate routine testing of cooling towers for Legionella in multifamily housing. Design, Setting, and Population: We utilized a mix of both qualitative and quantitative methods to explore the development, adoption, and implementation of the ordinance. Phone interviews were conducted with individuals from the City of Garland Health Department and apartment managers. Quantitative data included public health surveillance data on legionellosis. Main Outcome Measures: Barriers and facilitators of implementation, number and percentage of cooling towers from multifamily housing units that tested positive for Legionella by year, and number of legionellosis cases by year in Garland, Texas. Results: Study outcomes highlight key themes that facilitated the successful implementation of the Legionella testing mandate, including the importance of timing, leadership support, stakeholder engagement, and education and outreach. The number of contaminated cooling towers was reduced over time. Conclusion: Mandatory monitoring for legionella in a local jurisdiction may result in reduced risk of legionellosis from cooling towers through raising awareness and education of building owners and managers about the need to prevent, detect, and remediate legionella contamination in their building water systems. Garland, Texas, broke new ground in the United States in moving toward primary prevention of legionellosis. The ordinance may be useful both in serving to educate and increase awareness about the need for Legionella prevention and to monitor effectiveness of maintenance procedures. PMID:28141673
A non-iterative extension of the multivariate random effects meta-analysis.
Makambi, Kepher H; Seung, Hyunuk
2015-01-01
Multivariate methods in meta-analysis are becoming popular and more accepted in biomedical research despite computational issues in some of the techniques. A number of approaches, both iterative and non-iterative, have been proposed including the multivariate DerSimonian and Laird method by Jackson et al. (2010), which is non-iterative. In this study, we propose an extension of the method by Hartung and Makambi (2002) and Makambi (2001) to multivariate situations. A comparison of the bias and mean square error from a simulation study indicates that, in some circumstances, the proposed approach perform better than the multivariate DerSimonian-Laird approach. An example is presented to demonstrate the application of the proposed approach.
Objective and Perceived Weight: Associations with Risky Adolescent Sexual Behavior
Akers, Aletha Y.; Cohen, Elan D.; Marshal, Michael P.; Roebuck, Geoff; Yu, Lan; Hipwell, Alison E.
2016-01-01
CONTEXT Studies have shown that obesity is associated with increased sexual risk-taking, particularly among adolescent females, but the relationships between obesity, perceived weight and sexual risk behaviors are poorly understood. METHODS Integrative data analysis was performed that combined baseline data from the 1994–1995 National Longitudinal Study of Adolescent Health (from 17,606 respondents in grades 7–12) and the 1997 National Longitudinal Survey of Youth (from 7,752 respondents aged 12–16). Using six sexual behaviors measured in both data sets (age at first intercourse, various measures of contraceptive use and number of partners), cluster analysis was conducted that identified five distinct behavior clusters. Multivariate ordinal logistic regression analysis examined associations between adolescents’ weight status (categorized as underweight, normal-weight, overweight or obese) and weight perception and their cluster membership. RESULTS Among males, being underweight, rather than normal-weight, was negatively associated with membership in increasingly risky clusters (odds ratio, 0.5), as was the perception of being overweight, as opposed to about the right weight (0.8). However, being overweight was positively associated with males’ membership in increasingly risky clusters (1.3). Among females, being obese, rather than normal-weight, was negatively correlated with membership in increasingly risky clusters (0.8), while the perception of being overweight was positively correlated with such membership (1.1). CONCLUSIONS Both objective and subjective assessments of weight are associated with the clustering of risky sexual behaviors among adolescents, and these behavioral patterns differ by gender. PMID:27608419
Longitudinal Examination of Symptom Profiles among Breast Cancer Survivors
Avis, Nancy E.; Levine, Beverly; Marshall, Sarah A.; Ip, Edward H.
2017-01-01
Context Identification of cancer patients with similar symptom profiles may facilitate targeted symptom management. Objectives To identify subgroups of breast cancer survivors based on differential experience of symptoms, examine change in subgroup membership over time, and identify relevant characteristics and quality of life (QOL) among subgroups. Methods Secondary analyses of data from 653 breast cancer survivors recruited within 8 months of diagnosis who completed questionnaires at five timepoints. Hidden Markov modeling was used to: 1) formulate symptom profiles based on prevalence and severity of eight symptoms commonly associated with breast cancer, and 2) estimate probabilities of changing subgroup membership over 18 months of follow-up. Ordinal repeated measures were used to: 3) identify patient characteristics related to subgroup membership, and 4) evaluate the relationship between symptom subgroup and QOL. Results A seven-subgroup model provided the best fit: 1) low symptom burden, 2) mild fatigue, 3) mild fatigue and mild pain, 4) moderate fatigue and moderate pain, 5) moderate fatigue and moderate psychological, 6) moderate fatigue, mild pain, mild psychological; and 7) high symptom burden. Seventy percent of survivors remained in the same subgroup over time. In multivariable analyses, chemotherapy and greater illness intrusiveness were significantly related to greater symptom burden, while not being married or partnered, no difficulty paying for basics, and greater social support were protective. Higher symptom burden was associated with lower QOL. Survivors who reported psychological symptoms had significantly lower QOL than did survivors with pain symptoms. Conclusion Cancer survivors can be differentiated by their symptom profiles. PMID:28042076
Substance use in children of parents with chronic pain – the HUNT study
Kaasbøll, Jannike; Lydersen, Stian; Indredavik, Marit S
2014-01-01
Purpose The aim of the present study was to investigate possible associations between parental chronic pain and smoking, alcohol, and drug use in adolescent offspring. Methods Cross-sectional data from Nord-Trøndelag Health Study (HUNT 3), a Norwegian population-based health survey conducted in the period 2006–2008 was utilized. The present sample consisted of adolescents aged 13–18 years (n=3,227) for whom information was available on maternal and paternal health statuses. Results Results from multivariable ordinal and binary logistic regression analyses, adjusting for potential confounding factors (child age, parental age, education, and organ specific illness) indicated that the estimated odds ratios (OR) for smoking (OR =1.72, 95% confidence interval [CI] [1.00, 3.05], P=0.049) and alcohol intoxication (drunkenness) (OR =1.56, 95% CI [1.05, 2.33], P=0.029) were higher for boys whose mother and father had chronic pain, compared with boys for whom neither parent had chronic pain. These associations were slightly attenuated by additional adjustment for pain-related factors, such as parental smoking and symptoms of anxiety and depression. Parental chronic pain was not significantly associated with girls’ levels of substance use. There were significant interaction effects between parental chronic pain and child sex on offspring’s alcohol intoxication and smoking. Conclusion The present study expands on existing knowledge and provides groundwork for preventive and specific measures targeting substance use in families burdened with parental chronic pain. PMID:25187735
Multivariate Time Series Decomposition into Oscillation Components.
Matsuda, Takeru; Komaki, Fumiyasu
2017-08-01
Many time series are considered to be a superposition of several oscillation components. We have proposed a method for decomposing univariate time series into oscillation components and estimating their phases (Matsuda & Komaki, 2017 ). In this study, we extend that method to multivariate time series. We assume that several oscillators underlie the given multivariate time series and that each variable corresponds to a superposition of the projections of the oscillators. Thus, the oscillators superpose on each variable with amplitude and phase modulation. Based on this idea, we develop gaussian linear state-space models and use them to decompose the given multivariate time series. The model parameters are estimated from data using the empirical Bayes method, and the number of oscillators is determined using the Akaike information criterion. Therefore, the proposed method extracts underlying oscillators in a data-driven manner and enables investigation of phase dynamics in a given multivariate time series. Numerical results show the effectiveness of the proposed method. From monthly mean north-south sunspot number data, the proposed method reveals an interesting phase relationship.
Multivariate generalized multifactor dimensionality reduction to detect gene-gene interactions
2013-01-01
Background Recently, one of the greatest challenges in genome-wide association studies is to detect gene-gene and/or gene-environment interactions for common complex human diseases. Ritchie et al. (2001) proposed multifactor dimensionality reduction (MDR) method for interaction analysis. MDR is a combinatorial approach to reduce multi-locus genotypes into high-risk and low-risk groups. Although MDR has been widely used for case-control studies with binary phenotypes, several extensions have been proposed. One of these methods, a generalized MDR (GMDR) proposed by Lou et al. (2007), allows adjusting for covariates and applying to both dichotomous and continuous phenotypes. GMDR uses the residual score of a generalized linear model of phenotypes to assign either high-risk or low-risk group, while MDR uses the ratio of cases to controls. Methods In this study, we propose multivariate GMDR, an extension of GMDR for multivariate phenotypes. Jointly analysing correlated multivariate phenotypes may have more power to detect susceptible genes and gene-gene interactions. We construct generalized estimating equations (GEE) with multivariate phenotypes to extend generalized linear models. Using the score vectors from GEE we discriminate high-risk from low-risk groups. We applied the multivariate GMDR method to the blood pressure data of the 7,546 subjects from the Korean Association Resource study: systolic blood pressure (SBP) and diastolic blood pressure (DBP). We compare the results of multivariate GMDR for SBP and DBP to the results from separate univariate GMDR for SBP and DBP, respectively. We also applied the multivariate GMDR method to the repeatedly measured hypertension status from 5,466 subjects and compared its result with those of univariate GMDR at each time point. Results Results from the univariate GMDR and multivariate GMDR in two-locus model with both blood pressures and hypertension phenotypes indicate best combinations of SNPs whose interaction has significant association with risk for high blood pressures or hypertension. Although the test balanced accuracy (BA) of multivariate analysis was not always greater than that of univariate analysis, the multivariate BAs were more stable with smaller standard deviations. Conclusions In this study, we have developed multivariate GMDR method using GEE approach. It is useful to use multivariate GMDR with correlated multiple phenotypes of interests. PMID:24565370
77 FR 4720 - Appeal Proceedings Before the Commission
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-31
... ordinance disapprovals, management contract approvals and disapprovals, appeals before a presiding official... governs appeals of ordinance actions; part 539 addresses appeals of management contract actions; and part... management contract. The Commission believes that consolidating all appellate procedures in a new subchapter...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-13
... obtained by the fermentation of any infusion of decoction of barley, malt, hops, or any other similar... from the normal alcoholic fermentation of the juice of the grapes or other agricultural products...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-13
.... Beer means any alcoholic beverage obtained by the fermentation of any infusion or decoction of barley... Cedarville Rancheria. 03.150--Wine. Wine means the product obtained from the normal alcoholic fermentation of...
Three-Dimensional Orthogonal Co-ordinates
ERIC Educational Resources Information Center
Astin, J.
1974-01-01
A systematic approach to general orthogonal co-ordinates, suitable for use near the end of a beginning vector analysis course, is presented. It introduces students to tensor quantities and shows how equations and quantities needed in classical problems can be determined. (Author/LS)
Allen, James W A; Higham, Christopher W; Zajicek, Richard S; Watmough, Nicholas J; Ferguson, Stuart J
2002-01-01
The oxidized form of Paracoccus pantotrophus cytochrome cd(1) nitrite reductase, as isolated, has bis-histidinyl co-ordination of the c haem and His/Tyr co-ordination of the d(1) haem. On reduction, the haem co-ordinations change to His/Met and His/vacant respectively. If the latter form of the enzyme is reoxidized, a conformer is generated in which the ferric c haem is His/Met co-ordinated; this can revert to the 'as isolated' state of the enzyme over approx. 20 min at room temperature. However, addition of nitrite to the enzyme after a cycle of reduction and reoxidation produces a kinetically stable, all-ferric complex with nitrite bound to the d(1) haem and His/Met co-ordination of the c haem. This complex is catalytically active with the physiological electron donor protein pseudoazurin. The effective dissociation constant for nitrite is 2 mM. Evidence is presented that d(1) haem is optimized to bind nitrite, as opposed to other anions that are commonly good ligands to ferric haem. The all-ferric nitrite bound state of the enzyme could not be generated stoichiometrically by mixing nitrite with the 'as isolated' conformer of cytochrome cd(1) without redox cycling. PMID:12086580
Analyzing Multiple Outcomes in Clinical Research Using Multivariate Multilevel Models
Baldwin, Scott A.; Imel, Zac E.; Braithwaite, Scott R.; Atkins, David C.
2014-01-01
Objective Multilevel models have become a standard data analysis approach in intervention research. Although the vast majority of intervention studies involve multiple outcome measures, few studies use multivariate analysis methods. The authors discuss multivariate extensions to the multilevel model that can be used by psychotherapy researchers. Method and Results Using simulated longitudinal treatment data, the authors show how multivariate models extend common univariate growth models and how the multivariate model can be used to examine multivariate hypotheses involving fixed effects (e.g., does the size of the treatment effect differ across outcomes?) and random effects (e.g., is change in one outcome related to change in the other?). An online supplemental appendix provides annotated computer code and simulated example data for implementing a multivariate model. Conclusions Multivariate multilevel models are flexible, powerful models that can enhance clinical research. PMID:24491071
A Semi-Parametric Bayesian Mixture Modeling Approach for the Analysis of Judge Mediated Data
ERIC Educational Resources Information Center
Muckle, Timothy Joseph
2010-01-01
Existing methods for the analysis of ordinal-level data arising from judge ratings, such as the Multi-Facet Rasch model (MFRM, or the so-called Facets model) have been widely used in assessment in order to render fair examinee ability estimates in situations where the judges vary in their behavior or severity. However, this model makes certain…
ERIC Educational Resources Information Center
Watson, Bevilie R.
This book deals with the promotion of body awareness through use of educational gymnastics, with handicapped or non-handicapped but poorly coordinated children of all age levels. The method provides an analytical approach to movement, encourages children to listen to language, and assists them in creating their own activities. The activities and…
ERIC Educational Resources Information Center
Ugwu, Chinwe U.
2015-01-01
The National Commission for Mass Literacy, Adult and Non-Formal Education (NMEC) is the Federal Statutory Agency set up to co-ordinate all aspects of Non-Formal Education in Nigeria whether offered by government agencies or non-governmental organisations. This study looked at the existing Capacity Building Programme, the delivery methods, impact…
ERIC Educational Resources Information Center
Denbleyker, John Nickolas
2012-01-01
The shortcomings of the proportion above cut (PAC) statistic used so prominently in the educational landscape renders it a very problematic measure for making correct inferences with student test data. The limitations of PAC-based statistics are more pronounced with cross-test comparisons due to their dependency on cut-score locations. A better…
ERIC Educational Resources Information Center
Gonzalez-Fernandez, Marlis; Sein, Michael T.; Palmer, Jeffrey B.
2011-01-01
Purpose: To determine the clinical performance characteristics of the Mann Assessment of Swallowing Ability (MASA) for predicting aspiration (determined by videofluoroscopic swallowing study [VFSS]) in a mixed population. Method: We selected 133 cases clinically evaluated using MASA and VFSS from January through June 2007. Ordinal risk rating…
Assessing crown fire potential by linking models of surface and crown fire behavior
Joe H. Scott; Elizabeth D. Reinhardt
2001-01-01
Fire managers are increasingly concerned about the threat of crown fires, yet only now are quantitative methods for assessing crown fire hazard being developed. Links among existing mathematical models of fire behavior are used to develop two indices of crown fire hazard-the Torching Index and Crowning Index. These indices can be used to ordinate different forest...
Venkata Prasad, K; Samatha, K; Jagadeeswara Rao, D; Santhamma, C; Muthu, S; Mark Heron, B
2015-01-01
The vibrational frequencies of 3,4-dichlorobenzophenone (DCLBP) were obtained from the FT-IR and Raman spectral data, and evaluated based on the Density Functional Theory using the standard method B3LYP with 6-311+G(d,p) as the basis set. On the basis of potential energy distribution together with the normal-co-ordinate analysis and following the scaled quantum mechanical force methodology, the assignments for the various frequencies were described. The values of the electric dipole moment (μ) and the first-order hyperpolarizability (β) of the molecule were computed. The UV-absorption spectrum was also recorded to study the electronic transitions. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The NBO analysis, to study the intramolecular hyperconjugative interactions, was carried out. Mulliken's net charges were evaluated. The MEP and thermodynamic properties were also calculated. The electron density-based local reactivity descriptor, such as Fukui functions, was calculated to explain the chemical selectivity or reactivity site in 3,4-dichlorobenzophenone. Copyright © 2015 Elsevier B.V. All rights reserved.
Radiant heat exchange calculations in radiantly heated and cooled enclosures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chapman, K.S.; Zhang, P.
1995-08-01
This paper presents the development of a three-dimensional mathematical model to compute the radiant heat exchange between surfaces separated by a transparent and/or opaque medium. The model formulation accommodates arbitrary arrangements of the interior surfaces, as well as arbitrary placement of obstacles within the enclosure. The discrete ordinates radiation model is applied and has the capability to analyze the effect of irregular geometries and diverse surface temperatures and radiative properties. The model is verified by comparing calculated heat transfer rates to heat transfer rates determined from the exact radiosity method for four different enclosures. The four enclosures were selected tomore » provide a wide range of verification. This three-dimensional model based on the discrete ordinates method can be applied to a building to assist the design engineer in sizing a radiant heating system. By coupling this model with a convective and conductive heat transfer model and a thermal comfort model, the comfort levels throughout the room can be easily and efficiently mapped for a given radiant heater location. In addition, objects such as airplanes, trucks, furniture, and partitions can be easily incorporated to determine their effect on the performance of the radiant heating system.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, J.; Alpan, F. A.; Fischer, G.A.
2011-07-01
Traditional two-dimensional (2D)/one-dimensional (1D) SYNTHESIS methodology has been widely used to calculate fast neutron (>1.0 MeV) fluence exposure to reactor pressure vessel in the belt-line region. However, it is expected that this methodology cannot provide accurate fast neutron fluence calculation at elevations far above or below the active core region. A three-dimensional (3D) parallel discrete ordinates calculation for ex-vessel neutron dosimetry on a Westinghouse 4-Loop XL Pressurized Water Reactor has been done. It shows good agreement between the calculated results and measured results. Furthermore, the results show very different fast neutron flux values at some of the former plate locationsmore » and elevations above and below an active core than those calculated by a 2D/1D SYNTHESIS method. This indicates that for certain irregular reactor internal structures, where the fast neutron flux has a very strong local effect, it is required to use a 3D transport method to calculate accurate fast neutron exposure. (authors)« less
Li, Baoyue; Lingsma, Hester F; Steyerberg, Ewout W; Lesaffre, Emmanuel
2011-05-23
Logistic random effects models are a popular tool to analyze multilevel also called hierarchical data with a binary or ordinal outcome. Here, we aim to compare different statistical software implementations of these models. We used individual patient data from 8509 patients in 231 centers with moderate and severe Traumatic Brain Injury (TBI) enrolled in eight Randomized Controlled Trials (RCTs) and three observational studies. We fitted logistic random effects regression models with the 5-point Glasgow Outcome Scale (GOS) as outcome, both dichotomized as well as ordinal, with center and/or trial as random effects, and as covariates age, motor score, pupil reactivity or trial. We then compared the implementations of frequentist and Bayesian methods to estimate the fixed and random effects. Frequentist approaches included R (lme4), Stata (GLLAMM), SAS (GLIMMIX and NLMIXED), MLwiN ([R]IGLS) and MIXOR, Bayesian approaches included WinBUGS, MLwiN (MCMC), R package MCMCglmm and SAS experimental procedure MCMC.Three data sets (the full data set and two sub-datasets) were analysed using basically two logistic random effects models with either one random effect for the center or two random effects for center and trial. For the ordinal outcome in the full data set also a proportional odds model with a random center effect was fitted. The packages gave similar parameter estimates for both the fixed and random effects and for the binary (and ordinal) models for the main study and when based on a relatively large number of level-1 (patient level) data compared to the number of level-2 (hospital level) data. However, when based on relatively sparse data set, i.e. when the numbers of level-1 and level-2 data units were about the same, the frequentist and Bayesian approaches showed somewhat different results. The software implementations differ considerably in flexibility, computation time, and usability. There are also differences in the availability of additional tools for model evaluation, such as diagnostic plots. The experimental SAS (version 9.2) procedure MCMC appeared to be inefficient. On relatively large data sets, the different software implementations of logistic random effects regression models produced similar results. Thus, for a large data set there seems to be no explicit preference (of course if there is no preference from a philosophical point of view) for either a frequentist or Bayesian approach (if based on vague priors). The choice for a particular implementation may largely depend on the desired flexibility, and the usability of the package. For small data sets the random effects variances are difficult to estimate. In the frequentist approaches the MLE of this variance was often estimated zero with a standard error that is either zero or could not be determined, while for Bayesian methods the estimates could depend on the chosen "non-informative" prior of the variance parameter. The starting value for the variance parameter may be also critical for the convergence of the Markov chain.
Multivariate Phylogenetic Comparative Methods: Evaluations, Comparisons, and Recommendations.
Adams, Dean C; Collyer, Michael L
2018-01-01
Recent years have seen increased interest in phylogenetic comparative analyses of multivariate data sets, but to date the varied proposed approaches have not been extensively examined. Here we review the mathematical properties required of any multivariate method, and specifically evaluate existing multivariate phylogenetic comparative methods in this context. Phylogenetic comparative methods based on the full multivariate likelihood are robust to levels of covariation among trait dimensions and are insensitive to the orientation of the data set, but display increasing model misspecification as the number of trait dimensions increases. This is because the expected evolutionary covariance matrix (V) used in the likelihood calculations becomes more ill-conditioned as trait dimensionality increases, and as evolutionary models become more complex. Thus, these approaches are only appropriate for data sets with few traits and many species. Methods that summarize patterns across trait dimensions treated separately (e.g., SURFACE) incorrectly assume independence among trait dimensions, resulting in nearly a 100% model misspecification rate. Methods using pairwise composite likelihood are highly sensitive to levels of trait covariation, the orientation of the data set, and the number of trait dimensions. The consequences of these debilitating deficiencies are that a user can arrive at differing statistical conclusions, and therefore biological inferences, simply from a dataspace rotation, like principal component analysis. By contrast, algebraic generalizations of the standard phylogenetic comparative toolkit that use the trace of covariance matrices are insensitive to levels of trait covariation, the number of trait dimensions, and the orientation of the data set. Further, when appropriate permutation tests are used, these approaches display acceptable Type I error and statistical power. We conclude that methods summarizing information across trait dimensions, as well as pairwise composite likelihood methods should be avoided, whereas algebraic generalizations of the phylogenetic comparative toolkit provide a useful means of assessing macroevolutionary patterns in multivariate data. Finally, we discuss areas in which multivariate phylogenetic comparative methods are still in need of future development; namely highly multivariate Ornstein-Uhlenbeck models and approaches for multivariate evolutionary model comparisons. © The Author(s) 2017. Published by Oxford University Press on behalf of the Systematic Biology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
ERIC Educational Resources Information Center
Berry, Kenneth J.; And Others
1977-01-01
A FORTRAN program, GAMMA, computes Goodman and Kruskal's coefficient of ordinal association, gamma, and Somer's coefficient. The program also provides associated standard errors, standard scores, and probability values. (Author/JKS)
James S. Wakeley; Michael P. Guilfoyle; Terry J. Antrobus; Richard A. Fischer; Wylie C. Jr. Barrow; Paul B. Hamel
2007-01-01
We used an ordination approach to identify factors important to the organization of breeding bird communities in three floodplains: Cache River, Arkansas (AR), Iatt Creek, Louisiana '(LA), and the Coosawhatchie River, South Carolina (SC), USA.
49 CFR 397.3 - State and local laws, ordinances, and regulations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS TRANSPORTATION OF HAZARDOUS MATERIALS; DRIVING AND PARKING RULES General § 397.3 State and local laws, ordinances, and regulations. Every motor vehicle containing hazardous materials must be driven...
Comparative Robustness of Recent Methods for Analyzing Multivariate Repeated Measures Designs
ERIC Educational Resources Information Center
Seco, Guillermo Vallejo; Gras, Jaime Arnau; Garcia, Manuel Ato
2007-01-01
This study evaluated the robustness of two recent methods for analyzing multivariate repeated measures when the assumptions of covariance homogeneity and multivariate normality are violated. Specifically, the authors' work compares the performance of the modified Brown-Forsythe (MBF) procedure and the mixed-model procedure adjusted by the…
Normal co-ordinate analysis of 1, 8-dibromooctane
NASA Astrophysics Data System (ADS)
Singh, Devinder; Jaggi, Neena; Singh, Nafa
2010-02-01
The organic compound 1,8-dibromooctane (1,8-DBO) exists in liquid phase at ambient temperatures and has versatile synthetic applications. In its liquid phase 1,8-DBO has been expected to exist in four most probable conformations, with all its carbon atoms in the same plane, having symmetries C 2h , C i , C 2 and C 1 . In the present study a detailed vibrational analysis in terms of assignment of Fourier transform infrared (FT-IR) and Raman bands of this molecule using normal co-ordinate calculations has been done. A systematic set of symmetry co-ordinates has been constructed for this molecule and normal co-ordinate analysis is carried out using the computer program MOLVIB. The force-field transferred from already studied lower chain bromo-alkanes is subjected to refinement so as to fit the observed infrared and Raman frequencies with those of calculated ones. The potential energy distribution (PED) has also been calculated for each mode of vibration of the molecule for the assumed conformations.
An experimental test of CSR theory using a globally calibrated ordination method
Li, Yuanzhi
2017-01-01
Can CSR theory, in conjunction with a recently proposed globally calibrated CSR ordination (“StrateFy”), using only three easily measured leaf traits (leaf area, specific leaf area and leaf dry matter content) predict the functional signature of herbaceous vegetation along experimentally manipulated gradients of soil fertility and disturbance? To determine this, we grew 37 herbaceous species in mixture for five years in 24 experimental mesocosms differing in factorial levels of soil resources (stress) and density-independent mortality (disturbance). We measured 16 different functional traits and then ordinated the resulting vegetation within the CSR triangle using StrateFy. We then calculated community-weighted mean (CWM) values of the competitor (CCWM), stress-tolerator (SCWM) and ruderal (RCWM) scores for each mesocosm. We found a significant increase in SCWM from low to high stress mesocosms, and an increase in RCWM from lowly to highly disturbed mesocosms. However, CCWM did not decline significantly as intensity of stress or disturbance increased, as predicted by CSR theory. This last result likely arose because our herbaceous species were relatively poor competitors in global comparisons and thus no strong competitors in our species pool were selectively favoured in low stress and low disturbed mesocosms. Variation in the 13 other traits, not used by StrateFy, largely argeed with the predictions of CSR theory. StrateFy worked surprisingly well in our experimental study except for the C-dimension. Despite loss of some precision, it has great potential applicability in future studies due to its simplicity and generality. PMID:28388622
An experimental test of CSR theory using a globally calibrated ordination method.
Li, Yuanzhi; Shipley, Bill
2017-01-01
Can CSR theory, in conjunction with a recently proposed globally calibrated CSR ordination ("StrateFy"), using only three easily measured leaf traits (leaf area, specific leaf area and leaf dry matter content) predict the functional signature of herbaceous vegetation along experimentally manipulated gradients of soil fertility and disturbance? To determine this, we grew 37 herbaceous species in mixture for five years in 24 experimental mesocosms differing in factorial levels of soil resources (stress) and density-independent mortality (disturbance). We measured 16 different functional traits and then ordinated the resulting vegetation within the CSR triangle using StrateFy. We then calculated community-weighted mean (CWM) values of the competitor (CCWM), stress-tolerator (SCWM) and ruderal (RCWM) scores for each mesocosm. We found a significant increase in SCWM from low to high stress mesocosms, and an increase in RCWM from lowly to highly disturbed mesocosms. However, CCWM did not decline significantly as intensity of stress or disturbance increased, as predicted by CSR theory. This last result likely arose because our herbaceous species were relatively poor competitors in global comparisons and thus no strong competitors in our species pool were selectively favoured in low stress and low disturbed mesocosms. Variation in the 13 other traits, not used by StrateFy, largely argeed with the predictions of CSR theory. StrateFy worked surprisingly well in our experimental study except for the C-dimension. Despite loss of some precision, it has great potential applicability in future studies due to its simplicity and generality.
Wilson, Bethany J; Nicholas, Frank W; James, John W; Wade, Claire M; Tammen, Imke; Raadsma, Herman W; Castle, Kao; Thomson, Peter C
2012-01-01
Canine Hip Dysplasia (CHD) is a common, painful and debilitating orthopaedic disorder of dogs with a partly genetic, multifactorial aetiology. Worldwide, potential breeding dogs are evaluated for CHD using radiographically based screening schemes such as the nine ordinally-scored British Veterinary Association Hip Traits (BVAHTs). The effectiveness of selective breeding based on screening results requires that a significant proportion of the phenotypic variation is caused by the presence of favourable alleles segregating in the population. This proportion, heritability, was measured in a cohort of 13,124 Australian German Shepherd Dogs born between 1976 and 2005, displaying phenotypic variation for BVAHTs, using ordinal, linear and binary mixed models fitted by a Restricted Maximum Likelihood method. Heritability estimates for the nine BVAHTs ranged from 0.14-0.24 (ordinal models), 0.14-0.25 (linear models) and 0.12-0.40 (binary models). Heritability for the summed BVAHT phenotype was 0.30 ± 0.02. The presence of heritable variation demonstrates that selection based on BVAHTs has the potential to improve BVAHT scores in the population. Assuming a genetic correlation between BVAHT scores and CHD-related pain and dysfunction, the welfare of Australian German Shepherds can be improved by continuing to consider BVAHT scores in the selection of breeding dogs, but that as heritability values are only moderate in magnitude the accuracy, and effectiveness, of selection could be improved by the use of Estimated Breeding Values in preference to solely phenotype based selection of breeding animals.
Carter, Allison; Eun Min, Jeong; Chau, William; Lima, Viviane D.; Kestler, Mary; Pick, Neora; Money, Deborah; Montaner, Julio S G.; Hogg, Robert S.; Kaida, Angela
2014-01-01
Objectives We measured gender differences in “Quality of Care” (QOC) during the first year after initiation of antiretroviral therapy and investigated factors associated with poorer QOC among women. Design QOC was estimated using the Programmatic Compliance Score (PCS), a validated metric associated with all-cause mortality, among all patients (≥19 years) who initiated ART in British Columbia, Canada (2000–2010). Methods PCS includes six indicators of non-compliance with treatment initiation guidelines at baseline (not having drug resistance testing before treatment; starting on a non-recommended regimen; starting therapy at CD4<200 cells/mm3) and during first-year follow-up (receiving <3 CD4 tests; receiving <3 viral load tests; not achieving viral suppression within six months). Summary scores range from 0–6; higher scores indicate poorer QOC. Multivariable ordinal logistic regression was used to measure if female gender was an independent predictor of poorer QOC and factors associated with poorer QOC among women. Results QOC was determined for 3,642 patients (20% women). At baseline: 42% of women (34% men) did not have resistance testing before treatment; 17% of women (9% men) started on a non-recommended regimen (all p<0.001). At follow-up: 17% of women (11% men) received <3 CD4; 17% of women (11% men) received <3 VL; 50% of women (41% men) did not achieve viral suppression (all p<0.001). Overall, QOC was better among men (mean PSC = 1.54 (SD = 1.30)) compared with women (mean = 1.89 (SD = 1.37); p<0.001). In the multivariable model, female gender (AOR = 1.16 [95% CI: 0.99–1.35]; p = 0.062) remained associated with poorer QOC after covariate adjustment. Among women, those with injection drug use history, of Aboriginal ancestry, from Vancouver Island, and who initiated ART in earlier years were more likely to have poorer QOC. Conclusions Poorer QOC among women, especially from marginalized communities, demands that barriers undermining women's access to high-quality care be addressed to improve treatment and health for women with HIV. PMID:24642949
Understanding cultural significance, the edible mushrooms case
Garibay-Orijel, Roberto; Caballero, Javier; Estrada-Torres, Arturo; Cifuentes, Joaquín
2007-01-01
Background Cultural significance is a keystone in quantitative ethnobiology, which offers the possibility to make inferences about traditional nomenclature systems, use, appropriation and valuing of natural resources. In the present work, using as model the traditional mycological knowledge of Zapotecs from Oaxaca, Mexico, we analyze the cultural significance of wild edible resources. Methods In 2003 we applied 95 questionnaires to a random sample of informants. With this data we integrated the Edible Mushroom Cultural Significance Index. This index included eight variables: frequency of mention, perceived abundance, use frequency, taste, multifunctional food use, knowledge transmission, health and economy. Data were analyzed in an inductive perspective using ordination and grouping techniques to reveal the behavior of species in a cultural multivariate dimension. Results In each variable the species had different conducts. Cantharellus cibarius s.l. was the species with most frequency of mention. Pleurotus sp. had the highest perceived abundance. C. cibarius s.l. was the most frequently consumed species. Gomphus clavatus was the most palatable species and also ranked highest in the multifunctional food index. Cortinarius secc.Malacii sp. had the highest traditional importance. Only Tricholoma magnivelare was identified as a health enhancer. It also had the most economic importance. According to the compound index, C. cibarius s.l., the Amanita caesarea complex, Ramaria spp. and Neolentinus lepideus were the mushrooms with highest cultural significance. Multivariate analysis showed that interviewees identify three main groups of mushrooms: species with high traditional values, frequent consumption and known by the majority; species that are less known, infrequently consumed and without salient characteristics; and species with low traditional values, with high economic value and health enhancers. Conclusion The compound index divided the cultural significance into several cultural domains and showed the causes that underlie this phenomenon. This approach can be used in cross-cultural studies because it brings a list with the relative position of species among a cultural significance gradient. This list is suitable for comparisons and also it is flexible because cultural variables can be included or removed to adjust it to the nature of the different cultures or resources under study. PMID:17217539
77 FR 5183 - Review and Approval of Existing Ordinances or Resolutions; Repeal
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-02
... DEPARTMENT OF THE INTERIOR National Indian Gaming Commission 25 CFR Part 523 RIN 3141-AA45 Review and Approval of Existing Ordinances or Resolutions; Repeal AGENCY: National Indian Gaming Commission. ACTION: Final rule. SUMMARY: The National Indian Gaming Commission is repealing obsolete regulations...
32 CFR 510.1 - Private ministrations, sacraments, and ordinances.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 3 2010-07-01 2010-07-01 true Private ministrations, sacraments, and ordinances. 510.1 Section 510.1 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS CHAPLAINS § 510.1 Private ministrations, sacraments, and...
DOT National Transportation Integrated Search
2010-05-01
In March 2007, St. Louis County implemented a seat belt ordinance that allowed for traditional : enforcement procedures. In order to increase usage on St. Louis County roads, particularly on roadways : with fatal or disabling injury crashes, the St. ...
76 FR 63236 - Review and Approval of Existing Ordinances or Resolutions
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-12
... DEPARTMENT OF THE INTERIOR National Indian Gaming Commission 25 CFR Part 523 RIN 3141-AA45 Review and Approval of Existing Ordinances or Resolutions AGENCY: National Indian Gaming Commission, Interior. ACTION: Notice of proposed rulemaking. SUMMARY: On November 18, 2010, the National Indian Gaming...
32 CFR 510.1 - Private ministrations, sacraments, and ordinances.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 3 2012-07-01 2009-07-01 true Private ministrations, sacraments, and ordinances. 510.1 Section 510.1 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS CHAPLAINS § 510.1 Private ministrations, sacraments, and...
32 CFR 510.1 - Private ministrations, sacraments, and ordinances.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 32 National Defense 3 2014-07-01 2014-07-01 false Private ministrations, sacraments, and ordinances. 510.1 Section 510.1 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS CHAPLAINS § 510.1 Private ministrations, sacraments, and...
Leadership: Its Genealogy, Configuration and Trajectory
ERIC Educational Resources Information Center
Gronn, Peter
2010-01-01
This article provides a longitudinal analysis of leadership. In the first section of the article, the evidence reviewed indicates how, historically, leadership has been significant in various societal arrangements in the co-ordination of actions for collective purposes. Such co-ordination may also be facilitated through self-organisation, except…
40 CFR 35.2208 - Adoption of sewer use ordinance and user charge system.
Code of Federal Regulations, 2010 CFR
2010-07-01
... works is placed in operation. Further, the grantee shall implement the user charge system and sewer use ordinance for the useful life of the treatment works. ... GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works...
NASA Astrophysics Data System (ADS)
Godoy, William F.; DesJardin, Paul E.
2010-05-01
The application of flux limiters to the discrete ordinates method (DOM), SN, for radiative transfer calculations is discussed and analyzed for 3D enclosures for cases in which the intensities are strongly coupled to each other such as: radiative equilibrium and scattering media. A Newton-Krylov iterative method (GMRES) solves the final systems of linear equations along with a domain decomposition strategy for parallel computation using message passing libraries in a distributed memory system. Ray effects due to angular discretization and errors due to domain decomposition are minimized until small variations are introduced by these effects in order to focus on the influence of flux limiters on errors due to spatial discretization, known as numerical diffusion, smearing or false scattering. Results are presented for the DOM-integrated quantities such as heat flux, irradiation and emission. A variety of flux limiters are compared to "exact" solutions available in the literature, such as the integral solution of the RTE for pure absorbing-emitting media and isotropic scattering cases and a Monte Carlo solution for a forward scattering case. Additionally, a non-homogeneous 3D enclosure is included to extend the use of flux limiters to more practical cases. The overall balance of convergence, accuracy, speed and stability using flux limiters is shown to be superior compared to step schemes for any test case.
NASA Astrophysics Data System (ADS)
Heavens, A. F.; Seikel, M.; Nord, B. D.; Aich, M.; Bouffanais, Y.; Bassett, B. A.; Hobson, M. P.
2014-12-01
The Fisher Information Matrix formalism (Fisher 1935) is extended to cases where the data are divided into two parts (X, Y), where the expectation value of Y depends on X according to some theoretical model, and X and Y both have errors with arbitrary covariance. In the simplest case, (X, Y) represent data pairs of abscissa and ordinate, in which case the analysis deals with the case of data pairs with errors in both coordinates, but X can be any measured quantities on which Y depends. The analysis applies for arbitrary covariance, provided all errors are Gaussian, and provided the errors in X are small, both in comparison with the scale over which the expected signal Y changes, and with the width of the prior distribution. This generalizes the Fisher Matrix approach, which normally only considers errors in the `ordinate' Y. In this work, we include errors in X by marginalizing over latent variables, effectively employing a Bayesian hierarchical model, and deriving the Fisher Matrix for this more general case. The methods here also extend to likelihood surfaces which are not Gaussian in the parameter space, and so techniques such as DALI (Derivative Approximation for Likelihoods) can be generalized straightforwardly to include arbitrary Gaussian data error covariances. For simple mock data and theoretical models, we compare to Markov Chain Monte Carlo experiments, illustrating the method with cosmological supernova data. We also include the new method in the FISHER4CAST software.
NASA Technical Reports Server (NTRS)
Glick, B. J.
1985-01-01
Techniques for classifying objects into groups or clases go under many different names including, most commonly, cluster analysis. Mathematically, the general problem is to find a best mapping of objects into an index set consisting of class identifiers. When an a priori grouping of objects exists, the process of deriving the classification rules from samples of classified objects is known as discrimination. When such rules are applied to objects of unknown class, the process is denoted classification. The specific problem addressed involves the group classification of a set of objects that are each associated with a series of measurements (ratio, interval, ordinal, or nominal levels of measurement). Each measurement produces one variable in a multidimensional variable space. Cluster analysis techniques are reviewed and methods for incuding geographic location, distance measures, and spatial pattern (distribution) as parameters in clustering are examined. For the case of patterning, measures of spatial autocorrelation are discussed in terms of the kind of data (nominal, ordinal, or interval scaled) to which they may be applied.
Aisbett, B; Le Rossignol, P
2003-09-01
The VO2-power regression and estimated total energy demand for a 6-minute supra-maximal exercise test was predicted from a continuous incremental exercise test. Sub-maximal VO2-power co-ordinates were established from the last 40 seconds (s) of 150-second exercise stages. The precision of the estimated total energy demand was determined using the 95% confidence interval (95% CI) of the estimated total energy demand. The linearity of the individual VO2-power regression equations was determined using Pearson's correlation coefficient. The mean 95% CI of the estimated total energy demand was 5.9 +/- 2.5 mL O2 Eq x kg(-1) x min(-1), and the mean correlation coefficient was 0.9942 +/- 0.0042. The current study contends that the sub-maximal VO2-power co-ordinates from a continuous incremental exercise test can be used to estimate supra-maximal energy demand without compromising the precision of the accumulated oxygen deficit (AOD) method.
Peters, Colleen A; Thomas, Peyton A; Rieper, Kaitlyn B; Bratton, Susan P
2017-11-15
This study evaluated the influence of foraging preferences on microplastic ingestion by six marine fish species from the Texas Gulf Coast. A total of 1381 fish were analyzed and 42.4% contained ingested microplastic, inclusive of fiber (86.4%), microbead (12.9% %), and fragment (<1.0%) forms. Despite a substantial overlap in diet, ordination of ingested prey items clustered samples into distinctive species groupings, reflective of the foraging gradient among species. Orthopristis chrysoptera displayed the lowest overall frequency of microplastic ingestion and the most distinctive ordination grouping, indicating their selective invertebrate foraging preferences. Cluster analysis of O. chrysoptera most closely classified microplastic with the ingestion of benthic invertebrates, whereas the ingestion of microplastic by all other species most closely classified with the ingestion of vegetation and shrimp. O. chrysoptera, as selective invertebrate foragers, are less likely to ingest microplastics than species exhibiting generalist foraging preferences and methods of prey capture. Copyright © 2017 Elsevier Ltd. All rights reserved.
Emergence of spike correlations in periodically forced excitable systems
NASA Astrophysics Data System (ADS)
Reinoso, José A.; Torrent, M. C.; Masoller, Cristina
2016-09-01
In sensory neurons the presence of noise can facilitate the detection of weak information-carrying signals, which are encoded and transmitted via correlated sequences of spikes. Here we investigate the relative temporal order in spike sequences induced by a subthreshold periodic input in the presence of white Gaussian noise. To simulate the spikes, we use the FitzHugh-Nagumo model and to investigate the output sequence of interspike intervals (ISIs), we use the symbolic method of ordinal analysis. We find different types of relative temporal order in the form of preferred ordinal patterns that depend on both the strength of the noise and the period of the input signal. We also demonstrate a resonancelike behavior, as certain periods and noise levels enhance temporal ordering in the ISI sequence, maximizing the probability of the preferred patterns. Our findings could be relevant for understanding the mechanisms underlying temporal coding, by which single sensory neurons represent in spike sequences the information about weak periodic stimuli.
Bridges, Jackie; Meyer, Julienne; Glynn, Michael; Bentley, Jane; Reeves, Scott
2003-08-01
While more flexible models of service delivery are being introduced in UK health and social care, little is known about the impact of new roles, particularly support worker roles, on the work of existing practitioners. This action research study aimed to explore the impact of one such new role, that of interprofessional care co-ordinators (IPCCs). The general (internal) medical service of a UK hospital uses IPCCs to provide support to the interprofessional team and, in doing so, promote efficiency of acute bed use. Using a range of methods, mainly qualitative, this action research study sought to explore the characteristics and impact of the role on interprofessional team working. While the role's flexibility, autonomy and informality contributed to success in meeting its intended objectives, these characteristics also caused some tensions with interprofessional colleagues. These benefits and tensions mirror wider issues associated with the current modernisation agenda in UK health care.
van Wijngaarden, Edwin; Myers, Gary J.; Thurston, Sally W.; Shamlaye, Conrad F.; Davidson, Philip W.
2012-01-01
Purpose The potential for ill-informed causal inference is a major concern in published longitudinal studies evaluating impaired neurological function in children prenatally exposed to background levels of methyl mercury (MeHg). These studies evaluate a large number of developmental tests. We propose an alternative analysis strategy that reduces the number of comparisons tested in these studies. Methods Using data from the 9-year follow-up of 643 children in the Seychelles Child Development Study (SCDS), we grouped 18 individual endpoints into one overall ordinal outcome variable as well as by developmental domains. Subsequently, ordinal logistic regression analyses were performed. Results We did not find an association between prenatal MeHg exposure and developmental outcomes at 9 years of age. Conclusion Our proposed framework is more likely to result in a balanced interpretation of a posteriori associations. In addition, this new strategy should facilitate the use of complex epidemiological data in quantitative risk assessment. PMID:19205720
ERIC Educational Resources Information Center
Rhemtulla, Mijke; Brosseau-Liard, Patricia E.; Savalei, Victoria
2012-01-01
A simulation study compared the performance of robust normal theory maximum likelihood (ML) and robust categorical least squares (cat-LS) methodology for estimating confirmatory factor analysis models with ordinal variables. Data were generated from 2 models with 2-7 categories, 4 sample sizes, 2 latent distributions, and 5 patterns of category…
NASA Astrophysics Data System (ADS)
Li, Zhi-Hui; Peng, Ao-Ping; Zhang, Han-Xin; Yang, Jaw-Yen
2015-04-01
This article reviews rarefied gas flow computations based on nonlinear model Boltzmann equations using deterministic high-order gas-kinetic unified algorithms (GKUA) in phase space. The nonlinear Boltzmann model equations considered include the BGK model, the Shakhov model, the Ellipsoidal Statistical model and the Morse model. Several high-order gas-kinetic unified algorithms, which combine the discrete velocity ordinate method in velocity space and the compact high-order finite-difference schemes in physical space, are developed. The parallel strategies implemented with the accompanying algorithms are of equal importance. Accurate computations of rarefied gas flow problems using various kinetic models over wide ranges of Mach numbers 1.2-20 and Knudsen numbers 0.0001-5 are reported. The effects of different high resolution schemes on the flow resolution under the same discrete velocity ordinate method are studied. A conservative discrete velocity ordinate method to ensure the kinetic compatibility condition is also implemented. The present algorithms are tested for the one-dimensional unsteady shock-tube problems with various Knudsen numbers, the steady normal shock wave structures for different Mach numbers, the two-dimensional flows past a circular cylinder and a NACA 0012 airfoil to verify the present methodology and to simulate gas transport phenomena covering various flow regimes. Illustrations of large scale parallel computations of three-dimensional hypersonic rarefied flows over the reusable sphere-cone satellite and the re-entry spacecraft using almost the largest computer systems available in China are also reported. The present computed results are compared with the theoretical prediction from gas dynamics, related DSMC results, slip N-S solutions and experimental data, and good agreement can be found. The numerical experience indicates that although the direct model Boltzmann equation solver in phase space can be computationally expensive, nevertheless, the present GKUAs for kinetic model Boltzmann equations in conjunction with current available high-performance parallel computer power can provide a vital engineering tool for analyzing rarefied gas flows covering the whole range of flow regimes in aerospace engineering applications.
NASA Technical Reports Server (NTRS)
Capo, M. A.; Disney, R. K.
1971-01-01
The work performed in the following areas is summarized: (1) Analysis of Realistic nuclear-propelled vehicle was analyzed using the Marshall Space Flight Center computer code package. This code package includes one and two dimensional discrete ordinate transport, point kernel, and single scatter techniques, as well as cross section preparation and data processing codes, (2) Techniques were developed to improve the automated data transfer in the coupled computation method of the computer code package and improve the utilization of this code package on the Univac-1108 computer system. (3) The MSFC master data libraries were updated.
77 FR 34975 - Seminole Nation of Oklahoma-Alcohol Control and Enforcement Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-12
... government and the delivery of tribal services. DATES: Effective Date: This Ordinance is effective 30 days...) 781-4685; Fax: (918) 781-4649: or De Springer, Office of Indian Services, Bureau of Indian Affairs... Seminole Nation of Oklahoma and the delivery of important governmental services. Section 704. Application...
Ordination of Woody Vegetation in a Ouachita National Forest Watershed
Denise Marion; George Malanson
2004-01-01
Abstract - Species response to competition and other environmental gradients has important implications for forest ecosystem managers who desire to both maintain diversity and provide a sustained flow of forest goods and services. Woody species on a 140-acre watershed in the Ouachita National Forest are ordinated with detrended correspondence...
25 CFR 522.9 - Substitute approval.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Substitute approval. 522.9 Section 522.9 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.9 Substitute approval. If the Chairman fails to...
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Amendment. 522.3 Section 522.3 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.3 Amendment. (a) Within 15 days after adoption...
75 FR 32813 - St. Croix Chippewa Indians of Wisconsin Alcoholic Beverage Control Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-09
... DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs St. Croix Chippewa Indians of Wisconsin...: This notice publishes the Secretary's certification of the amended St. Croix Chippewa Indians of... Country. The St. Croix Tribal Council of the adopted this amended Liquor Ordinance on December 3, 2009...
Signing for the "No Smoking' ordinance in Southern California
William S. Folkman
1966-01-01
Symbolic signs, especially designed to aid enforcement of "no smoking" ordinances, had high visibility and were correctly interpreted by most travelers. Signs with words "NO" and "OK"' were superior to signs without these words. Observation and interpretation of the signs were greater among the younger persons and among those who...
75 FR 23280 - Choctaw Nation of Oklahoma Alcohol Control Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-03
... DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs Choctaw Nation of Oklahoma Alcohol Control... Choctaw Nation of Oklahoma's Alcohol Control Ordinance, which was adopted by the Tribal Council of the Choctaw Nation of Oklahoma under Council Bill CB-64-2010 enacted on March 13, 2010. The Alcohol Control...
Roadside Judgments in Children with Developmental Co-ordination Disorder
ERIC Educational Resources Information Center
Purcell, Catherine; Wann, John P.; Wilmut, Kate; Poulter, Damian
2011-01-01
As pedestrians, the perceptual ability to accurately judge the relative rate of approaching vehicles and select a suitable crossing gap requires sensitivity to looming. It also requires that crossing judgments are synchronized with motoric capabilities. Previous research has suggested that children with Developmental Co-ordination Disorder (DCD)…
4. PROPOSED C1 ASSEMBLY AND TESTING FACILITIES FOR THE ORDINANCE ...
4. PROPOSED C-1 ASSEMBLY AND TESTING FACILITIES FOR THE ORDINANCE GUIDED MISSILE CENTER AT REDSTONE ARSENAL, NEAR THE SOUTH END OF MADKIN MOUNTAIN. OCTOBER 1950, HANNES LUEHRSEN COLLECTION, MSFC MASTER PLANNING OFFICE. - Marshall Space Flight Center, East Test Area, Dodd Road, Huntsville, Madison County, AL
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-16
... carbon monoxide, hydrocarbons, nitrogen dioxide, photochemical oxidant, sulfur dioxide, and particulate... rely on local dust ordinances, completion of local road paving projects, and regulation of emissions from industrial processing activities. Among the local dust ordinances referred to in these four plans...
75 FR 62853 - Reno-Sparks Indian Colony Liquor Control Ordinance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-13
... alcohol, hydrated oxide or ethyl, or spirit or wine, which is commonly produced by the fermentation or... ordinance. (iii) ``Beer'' shall mean any beverage obtained by the alcoholic fermentation of any infusion or.... (xix) ``Wine'' shall mean any alcoholic beverage obtained by fermentation of fruits (grapes, berries...
40 CFR 35.2130 - Sewer use ordinance.
Code of Federal Regulations, 2012 CFR
2012-07-01
... integrity of the treatment works; cause violation of effluent or water quality limitations; or preclude the... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2130 Sewer use ordinance. The... any new connections from inflow sources into the treatment works and require that new sewers and...
40 CFR 35.2130 - Sewer use ordinance.
Code of Federal Regulations, 2014 CFR
2014-07-01
... integrity of the treatment works; cause violation of effluent or water quality limitations; or preclude the... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2130 Sewer use ordinance. The... any new connections from inflow sources into the treatment works and require that new sewers and...
Probability Elicitation Under Severe Time Pressure: A Rank-Based Method.
Jaspersen, Johannes G; Montibeller, Gilberto
2015-07-01
Probability elicitation protocols are used to assess and incorporate subjective probabilities in risk and decision analysis. While most of these protocols use methods that have focused on the precision of the elicited probabilities, the speed of the elicitation process has often been neglected. However, speed is also important, particularly when experts need to examine a large number of events on a recurrent basis. Furthermore, most existing elicitation methods are numerical in nature, but there are various reasons why an expert would refuse to give such precise ratio-scale estimates, even if highly numerate. This may occur, for instance, when there is lack of sufficient hard evidence, when assessing very uncertain events (such as emergent threats), or when dealing with politicized topics (such as terrorism or disease outbreaks). In this article, we adopt an ordinal ranking approach from multicriteria decision analysis to provide a fast and nonnumerical probability elicitation process. Probabilities are subsequently approximated from the ranking by an algorithm based on the principle of maximum entropy, a rule compatible with the ordinal information provided by the expert. The method can elicit probabilities for a wide range of different event types, including new ways of eliciting probabilities for stochastically independent events and low-probability events. We use a Monte Carlo simulation to test the accuracy of the approximated probabilities and try the method in practice, applying it to a real-world risk analysis recently conducted for DEFRA (the U.K. Department for the Environment, Farming and Rural Affairs): the prioritization of animal health threats. © 2015 Society for Risk Analysis.
Goldie, Fraser C; Fulton, Rachael L; Dawson, Jesse; Bluhmki, Erich; Lees, Kennedy R
2014-08-01
Clinical trials for acute ischemic stroke treatment require large numbers of participants and are expensive to conduct. Methods that enhance statistical power are therefore desirable. We explored whether this can be achieved by a measure incorporating both early and late measures of outcome (e.g. seven-day NIH Stroke Scale combined with 90-day modified Rankin scale). We analyzed sensitivity to treatment effect, using proportional odds logistic regression for ordinal scales and generalized estimating equation method for global outcomes, with all analyses adjusted for baseline severity and age. We ran simulations to assess relations between sample size and power for ordinal scales and corresponding global outcomes. We used R version 2·12·1 (R Development Core Team. R Foundation for Statistical Computing, Vienna, Austria) for simulations and SAS 9·2 (SAS Institute Inc., Cary, NC, USA) for all other analyses. Each scale considered for combination was sensitive to treatment effect in isolation. The mRS90 and NIHSS90 had adjusted odds ratio of 1·56 and 1·62, respectively. Adjusted odds ratio for global outcomes of the combination of mRS90 with NIHSS7 and NIHSS90 with NIHSS7 were 1·69 and 1·73, respectively. The smallest sample sizes required to generate statistical power ≥80% for mRS90, NIHSS7, and global outcomes of mRS90 and NIHSS7 combined and NIHSS90 and NIHSS7 combined were 500, 490, 400, and 380, respectively. When data concerning both early and late outcomes are combined into a global measure, there is increased sensitivity to treatment effect compared with solitary ordinal scales. This delivers a 20% reduction in required sample size at 80% power. Combining early with late outcomes merits further consideration. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.