Statistical mechanics and the ontological interpretation
NASA Astrophysics Data System (ADS)
Bohm, D.; Hiley, B. J.
1996-06-01
To complete our ontological interpretation of quantum theory we have to conclude a treatment of quantum statistical mechanics. The basic concepts in the ontological approach are the particle and the wave function. The density matrix cannot play a fundamental role here. Therefore quantum statistical mechanics will require a further statistical distribution over wave functions in addition to the distribution of particles that have a specified wave function. Ultimately the wave function of the universe will he required, but we show that if the universe in not in thermodynamic equilibrium then it can he treated in terms of weakly interacting large scale constituents that are very nearly independent of each other. In this way we obtain the same results as those of the usual approach within the framework of the ontological interpretation.
Statistical weld process monitoring with expert interpretation
Cook, G.E.; Barnett, R.J.; Strauss, A.M.; Thompson, F.M. Jr.
1996-12-31
A statistical weld process monitoring system is described. Using data of voltage, current, wire feed speed, gas flow rate, travel speed, and elapsed arc time collected while welding, the welding statistical process control (SPC) tool provides weld process quality control by implementing techniques of data trending analysis, tolerance analysis, and sequential analysis. For purposes of quality control, the control limits required for acceptance are specified in the weld procedure acceptance specifications. The control charts then provide quality assurance documentation for each weld. The statistical data trending analysis performed by the SPC program is not only valuable as a quality assurance monitoring and documentation system, it is also valuable in providing diagnostic assistance in troubleshooting equipment and material problems. Possible equipment/process problems are identified and matched with features of the SPC control charts. To aid in interpreting the voluminous statistical output generated by the SPC system, a large number of If-Then rules have been devised for providing computer-based expert advice for pinpointing problems based on out-of-limit variations of the control charts. The paper describes the SPC monitoring tool and the rule-based expert interpreter that has been developed for relating control chart trends to equipment/process problems.
NASA Astrophysics Data System (ADS)
Tadaki, Kohtaro
2010-12-01
The statistical mechanical interpretation of algorithmic information theory (AIT, for short) was introduced and developed by our former works [K. Tadaki, Local Proceedings of CiE 2008, pp. 425-434, 2008] and [K. Tadaki, Proceedings of LFCS'09, Springer's LNCS, vol. 5407, pp. 422-440, 2009], where we introduced the notion of thermodynamic quantities, such as partition function Z(T), free energy F(T), energy E(T), statistical mechanical entropy S(T), and specific heat C(T), into AIT. We then discovered that, in the interpretation, the temperature T equals to the partial randomness of the values of all these thermodynamic quantities, where the notion of partial randomness is a stronger representation of the compression rate by means of program-size complexity. Furthermore, we showed that this situation holds for the temperature T itself, which is one of the most typical thermodynamic quantities. Namely, we showed that, for each of the thermodynamic quantities Z(T), F(T), E(T), and S(T) above, the computability of its value at temperature T gives a sufficient condition for T (0,1) to satisfy the condition that the partial randomness of T equals to T. In this paper, based on a physical argument on the same level of mathematical strictness as normal statistical mechanics in physics, we develop a total statistical mechanical interpretation of AIT which actualizes a perfect correspondence to normal statistical mechanics. We do this by identifying a microcanonical ensemble in the framework of AIT. As a result, we clarify the statistical mechanical meaning of the thermodynamic quantities of AIT.
Interpreting Educational Research Using Statistical Software.
ERIC Educational Resources Information Center
Evans, Elizabeth A.
A live demonstration of how a typical set of educational data can be examined using quantitative statistical software was conducted. The topic of tutorial support was chosen. Setting up a hypothetical research scenario, the researcher created 300 cases from random data generation adjusted to correct obvious error. Each case represented a student…
The Statistical Interpretation of Entropy: An Activity
ERIC Educational Resources Information Center
Timmberlake, Todd
2010-01-01
The second law of thermodynamics, which states that the entropy of an isolated macroscopic system can increase but will not decrease, is a cornerstone of modern physics. Ludwig Boltzmann argued that the second law arises from the motion of the atoms that compose the system. Boltzmann's statistical mechanics provides deep insight into the…
The Statistical Interpretation of Entropy: An Activity
NASA Astrophysics Data System (ADS)
Timmberlake, Todd
2010-11-01
The second law of thermodynamics, which states that the entropy of an isolated macroscopic system can increase but will not decrease, is a cornerstone of modern physics. Ludwig Boltzmann argued that the second law arises from the motion of the atoms that compose the system. Boltzmann's statistical mechanics provides deep insight into the functioning of the second law and also provided evidence for the existence of atoms at a time when many scientists (like Ernst Mach and Wilhelm Ostwald) were skeptical.
For a statistical interpretation of Helmholtz' thermal displacement
NASA Astrophysics Data System (ADS)
Podio-Guidugli, Paolo
2016-05-01
On moving from the classic papers by Einstein and Langevin on Brownian motion, two consistent statistical interpretations are given for the thermal displacement, a scalar field formally introduced by Helmholtz, whose time derivative is by definition the absolute temperature.
The Statistical Interpretation of Classical Thermodynamic Heating and Expansion Processes
ERIC Educational Resources Information Center
Cartier, Stephen F.
2011-01-01
A statistical model has been developed and applied to interpret thermodynamic processes typically presented from the macroscopic, classical perspective. Through this model, students learn and apply the concepts of statistical mechanics, quantum mechanics, and classical thermodynamics in the analysis of the (i) constant volume heating, (ii)…
On Interpreting Test Scores as Social Indicators: Statistical Considerations.
ERIC Educational Resources Information Center
Spencer, Bruce D.
1983-01-01
Because test scores are ordinal not cordinal attributes, the average test score often is a misleading way to summarize the scores of a group of individuals. Similarly, correlation coefficients may be misleading summary measures of association between test scores. Proper, readily interpretable, summary statistics are developed from a theory of…
Integrating statistical rock physics and sedimentology for quantitative seismic interpretation
NASA Astrophysics Data System (ADS)
Avseth, Per; Mukerji, Tapan; Mavko, Gary; Gonzalez, Ezequiel
This paper presents an integrated approach for seismic reservoir characterization that can be applied both in petroleum exploration and in hydrological subsurface analysis. We integrate fundamental concepts and models of rock physics, sedimentology, statistical pattern recognition, and information theory, with seismic inversions and geostatistics. Rock physics models enable us to link seismic amplitudes to geological facies and reservoir properties. Seismic imaging brings indirect, noninvasive, but nevertheless spatially exhaustive information about the reservoir properties that are not available from well data alone. Classification and estimation methods based on computational statistical techniques such as nonparametric Bayesian classification, Monte Carlo simulations and bootstrap, help to quantitatively measure the interpretation uncertainty and the mis-classification risk at each spatial location. Geostatistical stochastic simulations incorporate the spatial correlation and the small scale variability which is hard to capture with only seismic information because of the limits of resolution. Combining deterministic physical models with statistical techniques has provided us with a successful way of performing quantitative interpretation and estimation of reservoir properties from seismic data. These formulations identify not only the most likely interpretation but also the uncertainty of the interpretation, and serve as a guide for quantitative decision analysis. The methodology shown in this article is applied successfully to map petroleum reservoirs, and the examples are from relatively deeply buried oil fields. However, we suggest that this approach can also be carried out for improved characterization of shallow hydrologic aquifers using shallow seismic or GPR data.
Use and interpretation of statistics in wildlife journals
Tacha, Thomas C.; Warde, William D.; Burnham, Kenneth P.
1982-01-01
Use and interpretation of statistics in wildlife journals are reviewed, and suggestions for improvement are offered. Populations from which inferences are to be drawn should be clearly defined, and conclusions should be limited to the range of the data analyzed. Authors should be careful to avoid improper methods of plotting data and should clearly define the use of estimates of variance, standard deviation, standard error, or confidence intervals. Biological and statistical significant are often confused by authors and readers. Statistical hypothesis testing is a tool, and not every question should be answered by hypothesis testing. Meeting assumptions of hypothesis tests is the responsibility of authors, and assumptions should be reviewed before a test is employed. The use of statistical tools should be considered carefully both before and after gathering data.
Comparing survival curves using an easy to interpret statistic.
Hess, Kenneth R
2010-10-15
Here, I describe a statistic for comparing two survival curves that has a clear and obvious meaning and has a long history in biostatistics. Suppose we are comparing survival times associated with two treatments A and B. The statistic operates in such a way that if it takes on the value 0.95, then the interpretation is that a randomly chosen patient treated with A has a 95% chance of surviving longer than a randomly chosen patient treated with B. This statistic was first described in the 1950s, and was generalized in the 1960s to work with right-censored survival times. It is a useful and convenient measure for assessing differences between survival curves. Software for computing the statistic is readily available on the Internet. PMID:20732962
Adapting internal statistical models for interpreting visual cues to depth
Seydell, Anna; Knill, David C.; Trommershäuser, Julia
2010-01-01
The informativeness of sensory cues depends critically on statistical regularities in the environment. However, statistical regularities vary between different object categories and environments. We asked whether and how the brain changes the prior assumptions about scene statistics used to interpret visual depth cues when stimulus statistics change. Subjects judged the slants of stereoscopically presented figures by adjusting a virtual probe perpendicular to the surface. In addition to stereoscopic disparities, the aspect ratio of the stimulus in the image provided a “figural compression” cue to slant, whose reliability depends on the distribution of aspect ratios in the world. As we manipulated this distribution from regular to random and back again, subjects’ reliance on the compression cue relative to stereoscopic cues changed accordingly. When we randomly interleaved stimuli from shape categories (ellipses and diamonds) with different statistics, subjects gave less weight to the compression cue for figures from the category with more random aspect ratios. Our results demonstrate that relative cue weights vary rapidly as a function of recently experienced stimulus statistics, and that the brain can use different statistical models for different object categories. We show that subjects’ behavior is consistent with that of a broad class of Bayesian learning models. PMID:20465321
Pass-Fail Testing: Statistical Requirements and Interpretations
Gilliam, David; Leigh, Stefan; Rukhin, Andrew; Strawderman, William
2009-01-01
Performance standards for detector systems often include requirements for probability of detection and probability of false alarm at a specified level of statistical confidence. This paper reviews the accepted definitions of confidence level and of critical value. It describes the testing requirements for establishing either of these probabilities at a desired confidence level. These requirements are computable in terms of functions that are readily available in statistical software packages and general spreadsheet applications. The statistical interpretations of the critical values are discussed. A table is included for illustration, and a plot is presented showing the minimum required numbers of pass-fail tests. The results given here are applicable to one-sided testing of any system with performance characteristics conforming to a binomial distribution. PMID:27504221
Interpreting health statistics for policymaking: the story behind the headlines.
Walker, Neff; Bryce, Jennifer; Black, Robert E
2007-03-17
Politicians, policymakers, and public-health professionals make complex decisions on the basis of estimates of disease burden from different sources, many of which are "marketed" by skilled advocates. To help people who rely on such statistics make more informed decisions, we explain how health estimates are developed, and offer basic guidance on how to assess and interpret them. We describe the different levels of estimates used to quantify disease burden and its correlates; understanding how closely linked a type of statistic is to disease and death rates is crucial in designing health policies and programmes. We also suggest questions that people using such statistics should ask and offer tips to help separate advocacy from evidence-based positions. Global health agencies have a key role in communicating robust estimates of disease, as do policymakers at national and subnational levels where key public-health decisions are made. A common framework and standardised methods, building on the work of Child Health Epidemiology Reference Group (CHERG) and others, are urgently needed. PMID:17368157
Workplace statistical literacy for teachers: interpreting box plots
NASA Astrophysics Data System (ADS)
Pierce, Robyn; Chick, Helen
2013-06-01
As a consequence of the increased use of data in workplace environments, there is a need to understand the demands that are placed on users to make sense of such data. In education, teachers are being increasingly expected to interpret and apply complex data about student and school performance, and, yet it is not clear that they always have the appropriate knowledge and experience to interpret the graphs, tables and other data that they receive. This study examined the statistical literacy demands placed on teachers, with a particular focus on box plot representations. Although box plots summarise the data in a way that makes visual comparisons possible across sets of data, this study showed that teachers do not always have the necessary fluency with the representation to describe correctly how the data are distributed in the representation. In particular, a significant number perceived the size of the regions of the box plot to be depicting frequencies rather than density, and there were misconceptions associated with outlying data that were not displayed on the plot. As well, teachers' perceptions of box plots were found to relate to three themes: attitudes, perceived value and misconceptions.
NASA Astrophysics Data System (ADS)
Nyblade, Andrew A.; Pollack, Henry N.
1993-03-01
We address the extent to which regional variations in continental heat flow can be interpreted, making use of a heat flow data set from east and southern Africa. The first-order observation deriving from these heat flow measurements is a common pattern characterized in both regions by low heat flow in Archean cratons and higher heat flow in younger mobile belts. Two regional differences between east and southern Africa are superimposed on this common heat flow pattern: (1) heat flow in the Tanzania Craton is about 13 mW m -2 lower than in the Kalahari Craton, and (2) heat flow in the Mozambique Belt in east Africa is about 9 mW m -2 lower than in the southern African mobile belts, within about 250 km of the respective Archean cratons. The differences in heat flow between east and southern Africa suggest that the thermal structure of the lithosphere beneath these regions differs somewhat, and we attempt to resolve these differences in lithospheric thermal structure by examining four explanations that could account for the heat flow observations: (1) diminished heat flow in shallow boreholes in east Africa; (2) less crustal heat production in the regions of lower heat flow; (3) thicker lithosphere beneath the regions of lower heat flow; (4) cooler mantle beneath the areas of lower heat flow. We find it difficult to interpret uniquely the heat flow differences between east and southern Africa because available constraints on crustal heat production, crustal structure, lithospheric thickness and mantle temperatures are insufficient to discriminate among the possible explanations. Hence, extracting significant information about lithospheric thermal structure from regional heat flow variations requires more ancillary geochemical and geophysical information than Africa presently offers.
Statistical Interpretation of Natural and Technological Hazards in China
NASA Astrophysics Data System (ADS)
Borthwick, Alistair, ,, Prof.; Ni, Jinren, ,, Prof.
2010-05-01
China is prone to catastrophic natural hazards from floods, droughts, earthquakes, storms, cyclones, landslides, epidemics, extreme temperatures, forest fires, avalanches, and even tsunami. This paper will list statistics related to the six worst natural disasters in China over the past 100 or so years, ranked according to number of fatalities. The corresponding data for the six worst natural disasters in China over the past decade will also be considered. [The data are abstracted from the International Disaster Database, Centre for Research on the Epidemiology of Disasters (CRED), Université Catholique de Louvain, Brussels, Belgium, http://www.cred.be/ where a disaster is defined as occurring if one of the following criteria is fulfilled: 10 or more people reported killed; 100 or more people reported affected; a call for international assistance; or declaration of a state of emergency.] The statistics include the number of occurrences of each type of natural disaster, the number of deaths, the number of people affected, and the cost in billions of US dollars. Over the past hundred years, the largest disasters may be related to the overabundance or scarcity of water, and to earthquake damage. However, there has been a substantial relative reduction in fatalities due to water related disasters over the past decade, even though the overall numbers of people affected remain huge, as does the economic damage. This change is largely due to the efforts put in by China's water authorities to establish effective early warning systems, the construction of engineering countermeasures for flood protection, the implementation of water pricing and other measures for reducing excessive consumption during times of drought. It should be noted that the dreadful death toll due to the Sichuan Earthquake dominates recent data. Joint research has been undertaken between the Department of Environmental Engineering at Peking University and the Department of Engineering Science at Oxford
Workplace Statistical Literacy for Teachers: Interpreting Box Plots
ERIC Educational Resources Information Center
Pierce, Robyn; Chick, Helen
2013-01-01
As a consequence of the increased use of data in workplace environments, there is a need to understand the demands that are placed on users to make sense of such data. In education, teachers are being increasingly expected to interpret and apply complex data about student and school performance, and, yet it is not clear that they always have the…
A novel statistical analysis and interpretation of flow cytometry data
Banks, H.T.; Kapraun, D.F.; Thompson, W. Clayton; Peligero, Cristina; Argilaguet, Jordi; Meyerhans, Andreas
2013-01-01
A recently developed class of models incorporating the cyton model of population generation structure into a conservation-based model of intracellular label dynamics is reviewed. Statistical aspects of the data collection process are quantified and incorporated into a parameter estimation scheme. This scheme is then applied to experimental data for PHA-stimulated CD4+ T and CD8+ T cells collected from two healthy donors. This novel mathematical and statistical framework is shown to form the basis for accurate, meaningful analysis of cellular behaviour for a population of cells labelled with the dye carboxyfluorescein succinimidyl ester and stimulated to divide. PMID:23826744
Statistical Interpretation of the Local Field Inside Dielectrics.
ERIC Educational Resources Information Center
Berrera, Ruben G.; Mello, P. A.
1982-01-01
Compares several derivations of the Clausius-Mossotti relation to analyze consistently the nature of approximations used and their range of applicability. Also presents a statistical-mechanical calculation of the local field for classical system of harmonic oscillators interacting via the Coulomb potential. (Author/SK)
Confounded Statistical Analyses Hinder Interpretation of the NELP Report
ERIC Educational Resources Information Center
Paris, Scott G.; Luo, Serena Wenshu
2010-01-01
The National Early Literacy Panel (2008) report identified early predictors of reading achievement as good targets for instruction, and many of those skills are related to decoding. In this article, the authors suggest that the developmental trajectories of rapidly developing skills pose problems for traditional statistical analyses. Rapidly…
Statistical characteristics of MST radar echoes and its interpretation
NASA Technical Reports Server (NTRS)
Woodman, Ronald F.
1989-01-01
Two concepts of fundamental importance are reviewed: the autocorrelation function and the frequency power spectrum. In addition, some turbulence concepts, the relationship between radar signals and atmospheric medium statistics, partial reflection, and the characteristics of noise and clutter interference are discussed.
Interpretation of gamma-ray burst source count statistics
NASA Technical Reports Server (NTRS)
Petrosian, Vahe
1993-01-01
Ever since the discovery of gamma-ray bursts, the so-called log N-log S relation has been used for determination of their distances and distribution. This task has not been straightforward because of varying thresholds for the detection of bursts. Most of the current analyses of these data are couched in terms of ambiguous distributions, such as the distribution of Cp/Clim, the ratio of peak to threshold photon count rates, or the distribution of V/Vmax = (Cp/Clim) exp -3/2. It is shown that these distributions are not always a true reflection of the log N-log S relation. Some kind of deconvolution is required for obtaining the true log N-log S. Therefore, care is required in the interpretation of results of such analyses. A new method of analysis of these data is described, whereby the bivariate distribution of Cp and Clim is obtained directly from the data.
Need for Caution in Interpreting Extreme Weather Statistics
NASA Astrophysics Data System (ADS)
Sardeshmukh, P. D.; Compo, G. P.; Penland, M. C.
2011-12-01
Given the substantial anthropogenic contribution to 20th century global warming, it is tempting to seek an anthropogenic component in any unusual recent weather event, or more generally in any observed change in the statistics of extreme weather. This study cautions that such detection and attribution efforts may, however, very likely lead to wrong conclusions if the non-Gaussian aspects of the probability distributions of observed daily atmospheric variations, especially their skewness and heavy tails, are not explicitly taken into account. Departures of three or more standard deviations from the mean, although rare, are far more common in such a non-Gaussian world than they are in a Gaussian world. This exacerbates the already difficult problem of establishing the significance of changes in extreme value probabilities from historical climate records of limited length, using either raw histograms or Generalized Extreme Value (GEV) distributions fitted to the sample extreme values. A possible solution is suggested by the fact that the non-Gaussian aspects of the observed distributions are well captured by a general class of "Stochastically Generated Skewed distributions" (SGS distributions) recently introduced in the meteorological literature by Sardeshmukh and Sura (J. Climate 2009). These distributions arise from simple modifications to a red noise process and reduce to Gaussian distributions under appropriate limits. As such, they represent perhaps the simplest physically based non-Gaussian prototypes of the distributions of daily atmospheric variations. Fitting such SGS distributions to all (not just the extreme) values in 25, 50, or 100-yr daily records also yields corresponding extreme value distributions that are much less prone to sampling uncertainty than GEV distributions. For both of the above reasons, SGS distributions provide an attractive alternative for assessing the significance of changes in extreme weather statistics (including changes in the
Interpreting the flock algorithm from a statistical perspective.
Anderson, Eric C; Barry, Patrick D
2015-09-01
We show that the algorithm in the program flock (Duchesne & Turgeon 2009) can be interpreted as an estimation procedure based on a model essentially identical to the structure (Pritchard et al. 2000) model with no admixture and without correlated allele frequency priors. Rather than using MCMC, the flock algorithm searches for the maximum a posteriori estimate of this structure model via a simulated annealing algorithm with a rapid cooling schedule (namely, the exponent on the objective function →∞). We demonstrate the similarities between the two programs in a two-step approach. First, to enable rapid batch processing of many simulated data sets, we modified the source code of structure to use the flock algorithm, producing the program flockture. With simulated data, we confirmed that results obtained with flock and flockture are very similar (though flockture is some 200 times faster). Second, we simulated multiple large data sets under varying levels of population differentiation for both microsatellite and SNP genotypes. We analysed them with flockture and structure and assessed each program on its ability to cluster individuals to their correct subpopulation. We show that flockture yields results similar to structure albeit with greater variability from run to run. flockture did perform better than structure when genotypes were composed of SNPs and differentiation was moderate (FST= 0.022-0.032). When differentiation was low, structure outperformed flockture for both marker types. On large data sets like those we simulated, it appears that flock's reliance on inference rules regarding its 'plateau record' is not helpful. Interpreting flock's algorithm as a special case of the model in structure should aid in understanding the program's output and behaviour. PMID:25913195
A statistical model for interpreting computerized dynamic posturography data
NASA Technical Reports Server (NTRS)
Feiveson, Alan H.; Metter, E. Jeffrey; Paloski, William H.
2002-01-01
Computerized dynamic posturography (CDP) is widely used for assessment of altered balance control. CDP trials are quantified using the equilibrium score (ES), which ranges from zero to 100, as a decreasing function of peak sway angle. The problem of how best to model and analyze ESs from a controlled study is considered. The ES often exhibits a skewed distribution in repeated trials, which can lead to incorrect inference when applying standard regression or analysis of variance models. Furthermore, CDP trials are terminated when a patient loses balance. In these situations, the ES is not observable, but is assigned the lowest possible score--zero. As a result, the response variable has a mixed discrete-continuous distribution, further compromising inference obtained by standard statistical methods. Here, we develop alternative methodology for analyzing ESs under a stochastic model extending the ES to a continuous latent random variable that always exists, but is unobserved in the event of a fall. Loss of balance occurs conditionally, with probability depending on the realized latent ES. After fitting the model by a form of quasi-maximum-likelihood, one may perform statistical inference to assess the effects of explanatory variables. An example is provided, using data from the NIH/NIA Baltimore Longitudinal Study on Aging.
Impact of Equity Models and Statistical Measures on Interpretations of Educational Reform
ERIC Educational Resources Information Center
Rodriguez, Idaykis; Brewe, Eric; Sawtelle, Vashti; Kramer, Laird H.
2012-01-01
We present three models of equity and show how these, along with the statistical measures used to evaluate results, impact interpretation of equity in education reform. Equity can be defined and interpreted in many ways. Most equity education reform research strives to achieve equity by closing achievement gaps between groups. An example is given…
Statistical Interpretation of Key Comparison Reference Value and Degrees of Equivalence
Kacker, R. N.; Datla, R. U.; Parr, A. C.
2003-01-01
Key comparisons carried out by the Consultative Committees (CCs) of the International Committee of Weights and Measures (CIPM) or the Bureau International des Poids et Mesures (BIPM) are referred to as CIPM key comparisons. The outputs of a statistical analysis of the data from a CIPM key comparison are the key comparison reference value, the degrees of equivalence, and their associated uncertainties. The BIPM publications do not discuss statistical interpretation of these outputs. We discuss their interpretation under the following three statistical models: nonexistent laboratory-effects model, random laboratory-effects model, and systematic laboratory-effects model.
NASA Astrophysics Data System (ADS)
Kuić, Domagoj
2016-05-01
In this paper an alternative approach to statistical mechanics based on the maximum information entropy principle (MaxEnt) is examined, specifically its close relation with the Gibbs method of ensembles. It is shown that the MaxEnt formalism is the logical extension of the Gibbs formalism of equilibrium statistical mechanics that is entirely independent of the frequentist interpretation of probabilities only as factual (i.e. experimentally verifiable) properties of the real world. Furthermore, we show that, consistently with the law of large numbers, the relative frequencies of the ensemble of systems prepared under identical conditions (i.e. identical constraints) actually correspond to the MaxEnt probabilites in the limit of a large number of systems in the ensemble. This result implies that the probabilities in statistical mechanics can be interpreted, independently of the frequency interpretation, on the basis of the maximum information entropy principle.
Statistical Tools for the Interpretation of Enzootic West Nile virus Transmission Dynamics.
Caillouët, Kevin A; Robertson, Suzanne
2016-01-01
Interpretation of enzootic West Nile virus (WNV) surveillance indicators requires little advanced mathematical skill, but greatly enhances the ability of public health officials to prescribe effective WNV management tactics. Stepwise procedures for the calculation of mosquito infection rates (IR) and vector index (VI) are presented alongside statistical tools that require additional computation. A brief review of advantages and important considerations for each statistic's use is provided. PMID:27188561
The broad topic of biomarker research has an often-overlooked component: the documentation and interpretation of the surrounding chemical environment and other meta-data, especially from visualization, analytical, and statistical perspectives (Pleil et al. 2014; Sobus et al. 2011...
Interpreting Statistical Significance Test Results: A Proposed New "What If" Method.
ERIC Educational Resources Information Center
Kieffer, Kevin M.; Thompson, Bruce
As the 1994 publication manual of the American Psychological Association emphasized, "p" values are affected by sample size. As a result, it can be helpful to interpret the results of statistical significant tests in a sample size context by conducting so-called "what if" analyses. However, these methods can be inaccurate unless "corrected" effect…
Dotto, G L; Pinto, L A A; Hachicha, M A; Knani, S
2015-03-15
In this work, statistical physics treatment was employed to study the adsorption of food dyes onto chitosan films, in order to obtain new physicochemical interpretations at molecular level. Experimental equilibrium curves were obtained for the adsorption of four dyes (FD&C red 2, FD&C yellow 5, FD&C blue 2, Acid Red 51) at different temperatures (298, 313 and 328 K). A statistical physics formula was used to interpret these curves, and the parameters such as, number of adsorbed dye molecules per site (n), anchorage number (n'), receptor sites density (NM), adsorbed quantity at saturation (N asat), steric hindrance (τ), concentration at half saturation (c1/2) and molar adsorption energy (ΔE(a)) were estimated. The relation of the above mentioned parameters with the chemical structure of the dyes and temperature was evaluated and interpreted. PMID:25308634
On the Interpretation of Running Trends as Summary Statistics for Time Series Analysis
NASA Astrophysics Data System (ADS)
Vigo, Isabel M.; Trottini, Mario; Belda, Santiago
2016-04-01
In recent years, running trends analysis (RTA) has been widely used in climate applied research as summary statistics for time series analysis. There is no doubt that RTA might be a useful descriptive tool, but despite its general use in applied research, precisely what it reveals about the underlying time series is unclear and, as a result, its interpretation is unclear too. This work contributes to such interpretation in two ways: 1) an explicit formula is obtained for the set of time series with a given series of running trends, making it possible to show that running trends, alone, perform very poorly as summary statistics for time series analysis; and 2) an equivalence is established between RTA and the estimation of a (possibly nonlinear) trend component of the underlying time series using a weighted moving average filter. Such equivalence provides a solid ground for RTA implementation and interpretation/validation.
Statistical issues in the design, analysis and interpretation of animal carcinogenicity studies.
Haseman, J K
1984-01-01
Statistical issues in the design, analysis and interpretation of animal carcinogenicity studies are discussed. In the area of experimental design, issues that must be considered include randomization of animals, sample size considerations, dose selection and allocation of animals to experimental groups, and control of potentially confounding factors. In the analysis of tumor incidence data, survival differences among groups should be taken into account. It is important to try to distinguish between tumors that contribute to the death of the animal and "incidental" tumors discovered at autopsy in an animal dying of an unrelated cause. Life table analyses (appropriate for lethal tumors) and incidental tumor tests (appropriate for nonfatal tumors) are described, and the utilization of these procedures by the National Toxicology Program is discussed. Despite the fact that past interpretations of carcinogenicity data have tended to focus on pairwise comparisons in general and high-dose effects in particular, the importance of trend tests should not be overlooked, since these procedures are more sensitive than pairwise comparisons to the detection of carcinogenic effects. No rigid statistical "decision rule" should be employed in the interpretation of carcinogenicity data. Although the statistical significance of an observed tumor increase is perhaps the single most important piece of evidence used in the evaluation process, a number of biological factors must also be taken into account. The use of historical control data, the false-positive issue and the interpretation of negative trends are also discussed. PMID:6525993
de Irala, J; Fernandez-Crehuet Navajas, R; Serrano del Castillo, A
1997-03-01
This study describes the behavior of eight statistical programs (BMDP, EGRET, JMP, SAS, SPSS, STATA, STATISTIX, and SYSTAT) when performing a logistic regression with a simulated data set that contains a numerical problem created by the presence of a cell value equal to zero. The programs respond in different ways to this problem. Most of them give a warning, although many simultaneously present incorrect results, among which are confidence intervals that tend toward infinity. Such results can mislead the user. Various guidelines are offered for detecting these problems in actual analyses, and users are reminded of the importance of critical interpretation of the results of statistical programs. PMID:9162592
Impact of equity models and statistical measures on interpretations of educational reform
NASA Astrophysics Data System (ADS)
Rodriguez, Idaykis; Brewe, Eric; Sawtelle, Vashti; Kramer, Laird H.
2012-12-01
We present three models of equity and show how these, along with the statistical measures used to evaluate results, impact interpretation of equity in education reform. Equity can be defined and interpreted in many ways. Most equity education reform research strives to achieve equity by closing achievement gaps between groups. An example is given by the study by Lorenzo et al. that shows that interactive engagement methods lead to increased gender equity. In this paper, we reexamine the results of Lorenzo et al. through three models of equity. We find that interpretation of the results strongly depends on the model of equity chosen. Further, we argue that researchers must explicitly state their model of equity as well as use effect size measurements to promote clarity in education reform.
Menzerath-Altmann Law: Statistical Mechanical Interpretation as Applied to a Linguistic Organization
NASA Astrophysics Data System (ADS)
Eroglu, Sertac
2014-10-01
The distribution behavior described by the empirical Menzerath-Altmann law is frequently encountered during the self-organization of linguistic and non-linguistic natural organizations at various structural levels. This study presents a statistical mechanical derivation of the law based on the analogy between the classical particles of a statistical mechanical organization and the distinct words of a textual organization. The derived model, a transformed (generalized) form of the Menzerath-Altmann model, was termed as the statistical mechanical Menzerath-Altmann model. The derived model allows interpreting the model parameters in terms of physical concepts. We also propose that many organizations presenting the Menzerath-Altmann law behavior, whether linguistic or not, can be methodically examined by the transformed distribution model through the properly defined structure-dependent parameter and the energy associated states.
NASA Technical Reports Server (NTRS)
Shewhart, Mark
1991-01-01
Statistical Process Control (SPC) charts are one of several tools used in quality control. Other tools include flow charts, histograms, cause and effect diagrams, check sheets, Pareto diagrams, graphs, and scatter diagrams. A control chart is simply a graph which indicates process variation over time. The purpose of drawing a control chart is to detect any changes in the process signalled by abnormal points or patterns on the graph. The Artificial Intelligence Support Center (AISC) of the Acquisition Logistics Division has developed a hybrid machine learning expert system prototype which automates the process of constructing and interpreting control charts.
Misuse of statistics in the interpretation of data on low-level radiation
Hamilton, L.D.
1982-01-01
Four misuses of statistics in the interpretation of data of low-level radiation are reviewed: (1) post-hoc analysis and aggregation of data leading to faulty conclusions in the reanalysis of genetic effects of the atomic bomb, and premature conclusions on the Portsmouth Naval Shipyard data; (2) inappropriate adjustment for age and ignoring differences between urban and rural areas leading to potentially spurious increase in incidence of cancer at Rocky Flats; (3) hazard of summary statistics based on ill-conditioned individual rates leading to spurious association between childhood leukemia and fallout in Utah; and (4) the danger of prematurely published preliminary work with inadequate consideration of epidemiological problems - censored data - leading to inappropriate conclusions, needless alarm at the Portsmouth Naval Shipyard, and diversion of scarce research funds.
Two Easily Made Astronomical Telescopes.
ERIC Educational Resources Information Center
Hill, M.; Jacobs, D. J.
1991-01-01
The directions and diagrams for making a reflecting telescope and a refracting telescope are presented. These telescopes can be made by students out of plumbing parts and easily obtainable, inexpensive, optical components. (KR)
Soil VisNIR chemometric performance statistics should be interpreted as random variables
NASA Astrophysics Data System (ADS)
Brown, David J.; Gasch, Caley K.; Poggio, Matteo; Morgan, Cristine L. S.
2015-04-01
Chemometric models are normally evaluated using performance statistics such as the Standard Error of Prediction (SEP) or the Root Mean Squared Error of Prediction (RMSEP). These statistics are used to evaluate the quality of chemometric models relative to other published work on a specific soil property or to compare the results from different processing and modeling techniques (e.g. Partial Least Squares Regression or PLSR and random forest algorithms). Claims are commonly made about the overall success of an application or the relative performance of different modeling approaches assuming that these performance statistics are fixed population parameters. While most researchers would acknowledge that small differences in performance statistics are not important, rarely are performance statistics treated as random variables. Given that we are usually comparing modeling approaches for general application, and given that the intent of VisNIR soil spectroscopy is to apply chemometric calibrations to larger populations than are included in our soil-spectral datasets, it is more appropriate to think of performance statistics as random variables with variation introduced through the selection of samples for inclusion in a given study and through the division of samples into calibration and validation sets (including spiking approaches). Here we look at the variation in VisNIR performance statistics for the following soil-spectra datasets: (1) a diverse US Soil Survey soil-spectral library with 3768 samples from all 50 states and 36 different countries; (2) 389 surface and subsoil samples taken from US Geological Survey continental transects; (3) the Texas Soil Spectral Library (TSSL) with 3000 samples; (4) intact soil core scans of Texas soils with 700 samples; (5) approximately 400 in situ scans from the Pacific Northwest region; and (6) miscellaneous local datasets. We find the variation in performance statistics to be surprisingly large. This has important
NASA Astrophysics Data System (ADS)
Jha, Sanjeev Kumar; Comunian, Alessandro; Mariethoz, Gregoire; Kelly, Bryce F. J.
2014-10-01
We develop a stochastic approach to construct channelized 3-D geological models constrained to borehole measurements as well as geological interpretation. The methodology is based on simple 2-D geologist-provided sketches of fluvial depositional elements, which are extruded in the 3rd dimension. Multiple-point geostatistics (MPS) is used to impair horizontal variability to the structures by introducing geometrical transformation parameters. The sketches provided by the geologist are used as elementary training images, whose statistical information is expanded through randomized transformations. We demonstrate the applicability of the approach by applying it to modeling a fluvial valley filling sequence in the Maules Creek catchment, Australia. The facies models are constrained to borehole logs, spatial information borrowed from an analogue and local orientations derived from the present-day stream networks. The connectivity in the 3-D facies models is evaluated using statistical measures and transport simulations. Comparison with a statistically equivalent variogram-based model shows that our approach is more suited for building 3-D facies models that contain structures specific to the channelized environment and which have a significant influence on the transport processes.
NASA Astrophysics Data System (ADS)
Karuppiah, R.; Faldi, A.; Laurenzi, I.; Usadi, A.; Venkatesh, A.
2014-12-01
An increasing number of studies are focused on assessing the environmental footprint of different products and processes, especially using life cycle assessment (LCA). This work shows how combining statistical methods and Geographic Information Systems (GIS) with environmental analyses can help improve the quality of results and their interpretation. Most environmental assessments in literature yield single numbers that characterize the environmental impact of a process/product - typically global or country averages, often unchanging in time. In this work, we show how statistical analysis and GIS can help address these limitations. For example, we demonstrate a method to separately quantify uncertainty and variability in the result of LCA models using a power generation case study. This is important for rigorous comparisons between the impacts of different processes. Another challenge is lack of data that can affect the rigor of LCAs. We have developed an approach to estimate environmental impacts of incompletely characterized processes using predictive statistical models. This method is applied to estimate unreported coal power plant emissions in several world regions. There is also a general lack of spatio-temporal characterization of the results in environmental analyses. For instance, studies that focus on water usage do not put in context where and when water is withdrawn. Through the use of hydrological modeling combined with GIS, we quantify water stress on a regional and seasonal basis to understand water supply and demand risks for multiple users. Another example where it is important to consider regional dependency of impacts is when characterizing how agricultural land occupation affects biodiversity in a region. We developed a data-driven methodology used in conjuction with GIS to determine if there is a statistically significant difference between the impacts of growing different crops on different species in various biomes of the world.
Parameter Interpretation and Reduction for a Unified Statistical Mechanical Surface Tension Model.
Boyer, Hallie; Wexler, Anthony; Dutcher, Cari S
2015-09-01
Surface properties of aqueous solutions are important for environments as diverse as atmospheric aerosols and biocellular membranes. Previously, we developed a surface tension model for both electrolyte and nonelectrolyte aqueous solutions across the entire solute concentration range (Wexler and Dutcher, J. Phys. Chem. Lett. 2013, 4, 1723-1726). The model differentiated between adsorption of solute molecules in the bulk and surface of solution using the statistical mechanics of multilayer sorption solution model of Dutcher et al. (J. Phys. Chem. A 2013, 117, 3198-3213). The parameters in the model had physicochemical interpretations, but remained largely empirical. In the current work, these parameters are related to solute molecular properties in aqueous solutions. For nonelectrolytes, sorption tendencies suggest a strong relation with molecular size and functional group spacing. For electrolytes, surface adsorption of ions follows ion surface-bulk partitioning calculations by Pegram and Record (J. Phys. Chem. B 2007, 111, 5411-5417). PMID:26275040
Shafieloo, Arman
2012-05-01
By introducing Crossing functions and hyper-parameters I show that the Bayesian interpretation of the Crossing Statistics [1] can be used trivially for the purpose of model selection among cosmological models. In this approach to falsify a cosmological model there is no need to compare it with other models or assume any particular form of parametrization for the cosmological quantities like luminosity distance, Hubble parameter or equation of state of dark energy. Instead, hyper-parameters of Crossing functions perform as discriminators between correct and wrong models. Using this approach one can falsify any assumed cosmological model without putting priors on the underlying actual model of the universe and its parameters, hence the issue of dark energy parametrization is resolved. It will be also shown that the sensitivity of the method to the intrinsic dispersion of the data is small that is another important characteristic of the method in testing cosmological models dealing with data with high uncertainties.
Barber, Chris; Cayley, Alex; Hanser, Thierry; Harding, Alex; Heghes, Crina; Vessey, Jonathan D; Werner, Stephane; Weiner, Sandy K; Wichard, Joerg; Giddings, Amanda; Glowienke, Susanne; Parenty, Alexis; Brigo, Alessandro; Spirkl, Hans-Peter; Amberg, Alexander; Kemper, Ray; Greene, Nigel
2016-04-01
The relative wealth of bacterial mutagenicity data available in the public literature means that in silico quantitative/qualitative structure activity relationship (QSAR) systems can readily be built for this endpoint. A good means of evaluating the performance of such systems is to use private unpublished data sets, which generally represent a more distinct chemical space than publicly available test sets and, as a result, provide a greater challenge to the model. However, raw performance metrics should not be the only factor considered when judging this type of software since expert interpretation of the results obtained may allow for further improvements in predictivity. Enough information should be provided by a QSAR to allow the user to make general, scientifically-based arguments in order to assess and overrule predictions when necessary. With all this in mind, we sought to validate the performance of the statistics-based in vitro bacterial mutagenicity prediction system Sarah Nexus (version 1.1) against private test data sets supplied by nine different pharmaceutical companies. The results of these evaluations were then analysed in order to identify findings presented by the model which would be useful for the user to take into consideration when interpreting the results and making their final decision about the mutagenic potential of a given compound. PMID:26708083
NASA Technical Reports Server (NTRS)
Dean, W. T.; Stringer, E. J.
1979-01-01
Crimp-type connectors reduce assembly and disassembly time. With design, no switch preparation is necessary and socket contracts are crimped to wires inserted in module attached to back of toggle switch engaging pins inside module to make electrical connections. Wires are easily removed with standard detachment tool. Design can accommodate wires of any gage and as many terminals can be placed on switch as wire gage and switch dimensions will allow.
Design of easily testable systems
Rawat, S.S.
1988-01-01
This thesis presents structured testability techniques that can be applied to systolic arrays. Systolic arrays for signal processing have produced processing rates far in excess of general-purpose architecture. Fast testing is considered as one of the design criteria. The main goal is to derive test vectors for one- and two-dimensional systolic arrays. The author seeks to keep the number of test vectors independent of the size of the array under a generic fault model. The testable design is based on pseudo-exhaustive testing. Conventional testing uses Level Sensitive Scan Detection (LSSD) techniques which are very time consuming for an array of systolic processors. By making the testability analysis early the logic designer will be able to make early (and repeated) design trade-offs that make design for testability a simple extension of the design process. The author shows how one-dimensional sequential systolic arrays can be designed so that the faults can be easily detected and isolated. He also considers unilateral two-dimensional sequential arrays and suggests modifications to make them easily testable. Finally, he shows how a modified carry look ahead adder of arbitrary size can be tested with just 136 test vectors. Comparisons are made against the standard LSSD technique.
ERIC Educational Resources Information Center
Boysen, Guy A.
2015-01-01
Student evaluations of teaching are among the most accepted and important indicators of college teachers' performance. However, faculty and administrators can overinterpret small variations in mean teaching evaluations. The current research examined the effect of including statistical information on the interpretation of teaching evaluations.…
Yu, Victoria; Kishan, Amar U.; Cao, Minsong; Low, Daniel; Lee, Percy; Ruan, Dan
2014-03-15
Purpose: To demonstrate a new method of evaluating dose response of treatment-induced lung radiographic injury post-SBRT (stereotactic body radiotherapy) treatment and the discovery of bimodal dose behavior within clinically identified injury volumes. Methods: Follow-up CT scans at 3, 6, and 12 months were acquired from 24 patients treated with SBRT for stage-1 primary lung cancers or oligometastic lesions. Injury regions in these scans were propagated to the planning CT coordinates by performing deformable registration of the follow-ups to the planning CTs. A bimodal behavior was repeatedly observed from the probability distribution for dose values within the deformed injury regions. Based on a mixture-Gaussian assumption, an Expectation-Maximization (EM) algorithm was used to obtain characteristic parameters for such distribution. Geometric analysis was performed to interpret such parameters and infer the critical dose level that is potentially inductive of post-SBRT lung injury. Results: The Gaussian mixture obtained from the EM algorithm closely approximates the empirical dose histogram within the injury volume with good consistency. The average Kullback-Leibler divergence values between the empirical differential dose volume histogram and the EM-obtained Gaussian mixture distribution were calculated to be 0.069, 0.063, and 0.092 for the 3, 6, and 12 month follow-up groups, respectively. The lower Gaussian component was located at approximately 70% prescription dose (35 Gy) for all three follow-up time points. The higher Gaussian component, contributed by the dose received by planning target volume, was located at around 107% of the prescription dose. Geometrical analysis suggests the mean of the lower Gaussian component, located at 35 Gy, as a possible indicator for a critical dose that induces lung injury after SBRT. Conclusions: An innovative and improved method for analyzing the correspondence between lung radiographic injury and SBRT treatment dose has
A Decision Tree Approach to the Interpretation of Multivariate Statistical Techniques.
ERIC Educational Resources Information Center
Fok, Lillian Y.; And Others
1995-01-01
Discusses the nature, power, and limitations of four multivariate techniques: factor analysis, multiple analysis of variance, multiple regression, and multiple discriminant analysis. Shows how decision trees assist in interpreting results. (SK)
"What If" Analyses: Ways to Interpret Statistical Significance Test Results Using EXCEL or "R"
ERIC Educational Resources Information Center
Ozturk, Elif
2012-01-01
The present paper aims to review two motivations to conduct "what if" analyses using Excel and "R" to understand the statistical significance tests through the sample size context. "What if" analyses can be used to teach students what statistical significance tests really do and in applied research either prospectively to estimate what sample size…
Boyle temperature as a point of ideal gas in gentile statistics and its economic interpretation
NASA Astrophysics Data System (ADS)
Maslov, V. P.; Maslova, T. V.
2014-07-01
Boyle temperature is interpreted as the temperature at which the formation of dimers becomes impossible. To Irving Fisher's correspondence principle we assign two more quantities: the number of degrees of freedom, and credit. We determine the danger level of the mass of money M when the mutual trust between economic agents begins to fall.
2014-01-01
Background A new algorithm has been developed to enable the interpretation of black box models. The developed algorithm is agnostic to learning algorithm and open to all structural based descriptors such as fragments, keys and hashed fingerprints. The algorithm has provided meaningful interpretation of Ames mutagenicity predictions from both random forest and support vector machine models built on a variety of structural fingerprints. A fragmentation algorithm is utilised to investigate the model’s behaviour on specific substructures present in the query. An output is formulated summarising causes of activation and deactivation. The algorithm is able to identify multiple causes of activation or deactivation in addition to identifying localised deactivations where the prediction for the query is active overall. No loss in performance is seen as there is no change in the prediction; the interpretation is produced directly on the model’s behaviour for the specific query. Results Models have been built using multiple learning algorithms including support vector machine and random forest. The models were built on public Ames mutagenicity data and a variety of fingerprint descriptors were used. These models produced a good performance in both internal and external validation with accuracies around 82%. The models were used to evaluate the interpretation algorithm. Interpretation was revealed that links closely with understood mechanisms for Ames mutagenicity. Conclusion This methodology allows for a greater utilisation of the predictions made by black box models and can expedite further study based on the output for a (quantitative) structure activity model. Additionally the algorithm could be utilised for chemical dataset investigation and knowledge extraction/human SAR development. PMID:24661325
MacKinnon, David P.; Pirlott, Angela G.
2016-01-01
Statistical mediation methods provide valuable information about underlying mediating psychological processes, but the ability to infer that the mediator variable causes the outcome variable is more complex than widely known. Researchers have recently emphasized how violating assumptions about confounder bias severely limits causal inference of the mediator to dependent variable relation. Our article describes and addresses these limitations by drawing on new statistical developments in causal mediation analysis. We first review the assumptions underlying causal inference and discuss three ways to examine the effects of confounder bias when assumptions are violated. We then describe four approaches to address the influence of confounding variables and enhance causal inference, including comprehensive structural equation models, instrumental variable methods, principal stratification, and inverse probability weighting. Our goal is to further the adoption of statistical methods to enhance causal inference in mediation studies. PMID:25063043
Statistics Translated: A Step-by-Step Guide to Analyzing and Interpreting Data
ERIC Educational Resources Information Center
Terrell, Steven R.
2012-01-01
Written in a humorous and encouraging style, this text shows how the most common statistical tools can be used to answer interesting real-world questions, presented as mysteries to be solved. Engaging research examples lead the reader through a series of six steps, from identifying a researchable problem to stating a hypothesis, identifying…
Patton, Charles J.; Gilroy, Edward J.
1999-01-01
Data on which this report is based, including nutrient concentrations in synthetic reference samples determined concurrently with those in real samples, are extensive (greater than 20,000 determinations) and have been published separately. In addition to confirming the well-documented instability of nitrite in acidified samples, this study also demonstrates that when biota are removed from samples at collection sites by 0.45-micrometer membrane filtration, subsequent preservation with sulfuric acid or mercury (II) provides no statistically significant improvement in nutrient concentration stability during storage at 4 degrees Celsius for 30 days. Biocide preservation had no statistically significant effect on the 30-day stability of phosphorus concentrations in whole-water splits from any of the 15 stations, but did stabilize Kjeldahl nitrogen concentrations in whole-water splits from three data-collection stations where ammonium accounted for at least half of the measured Kjeldahl nitrogen.
Eide, I; Zahlsen, K
1996-01-01
The paper describes experimental and statistical methods for toxicokinetic evaluation of mixtures in inhalation experiments. Synthetic mixtures of three C9 n-paraffinic, naphthenic and aromatic hydrocarbons (n-nonane, trimethylcyclohexane and trimethylbenzene, respectively) were studied in the rat after inhalation for 12h. The hydrocarbons were mixed according to principles for statistical experimental design using mixture design at four vapour levels (75, 150, 300 and 450 ppm) to support an empirical model with linear, interaction and quadratic terms (Taylor polynome). Immediately after exposure, concentrations of hydrocarbons were measured by head space gas chromatography in blood, brain, liver, kidneys and perirenal fat. Multivariate data analysis and modelling were performed with PLS (projections to latent structures). The best models were obtained after removing all interaction terms, suggesting that there were no interactions between the hydrocarbons with respect to absorption and distribution. Uptake of paraffins and particularly aromatics is best described by quadratic models, whereas the uptake of the naphthenic hydrocarbons is nearly linear. All models are good, with high correlation (r2) and prediction properties (Q2), the latter after cross validation. The concentrations of aromates in blood were high compared to the other hydrocarbons. At concentrations below 250 ppm, the naphthene reached higher concentrations in the brain compared to the paraffin and the aromate. Statistical experimental design, multivariate data analysis and modelling have proved useful for the evaluation of synthetic mixtures. The principles may also be used in the design of liquid mixtures, which may be evaporated partially or completely. PMID:8740533
Logical, epistemological and statistical aspects of nature-nurture data interpretation.
Kempthorne, O
1978-03-01
In this paper the nature of the reasoning processes applied to the nature-nurture question is discussed in general and with particular reference to mental and behavioral traits. The nature of data analysis and analysis of variance is discussed. Necessarily, the nature of causation is considered. The notion that mere data analysis can establish "real" causation is attacked. Logic of quantitative genetic theory is reviewed briefly. The idea that heritability is meaningful in the human mental and behavioral arena is attacked. The conclusion is that the heredity-IQ controversy has been a "tale full of sound and fury, signifying nothing". To suppose that one can establish effects of an intervention process when it does not occur in the data is plainly ludicrous. Mere observational studies can easily lead to stupidities, and it is suggested that this has happened in the heredity-IQ arena. The idea that there are racial-genetic differences in mental abilities and behavioral traits of humans is, at best, no more than idle speculation. PMID:637918
Statistical interpretation of joint multiplicity distributions of neutrons and charged particles
NASA Astrophysics Data System (ADS)
Tõke, J.; Agnihotri, D. K.; Skulski, W.; Schröder, W. U.
2001-02-01
Experimental joint multiplicity distributions of neutrons and charged particles provide a striking signal of the characteristic decay processes of nuclear systems following energetic nuclear reactions. They present, therefore, a valuable tool for testing theoretical models for such decay processes. The power of this experimental tool is demonstrated by a comparison of an experimental joint multiplicity distribution to the predictions of different theoretical models of statistical decay of excited nuclear systems. It is shown that, while generally phase-space based models offer a quantitative description of the observed correlation pattern of such an experimental multiplicity distribution, some models of nuclear multifragmentation fail to account for salient features of the observed correlation.
Rapp, J.B.
1991-01-01
Q-mode factor analysis was used to quantitate the distribution of the major aliphatic hydrocarbon (n-alkanes, pristane, phytane) systems in sediments from a variety of marine environments. The compositions of the pure end members of the systems were obtained from factor scores and the distribution of the systems within each sample was obtained from factor loadings. All the data, from the diverse environments sampled (estuarine (San Francisco Bay), fresh-water (San Francisco Peninsula), polar-marine (Antarctica) and geothermal-marine (Gorda Ridge) sediments), were reduced to three major systems: a terrestrial system (mostly high molecular weight aliphatics with odd-numbered-carbon predominance), a mature system (mostly low molecular weight aliphatics without predominance) and a system containing mostly high molecular weight aliphatics with even-numbered-carbon predominance. With this statistical approach, it is possible to assign the percentage contribution from various sources to the observed distribution of aliphatic hydrocarbons in each sediment sample. ?? 1991.
Double precision errors in the logistic map: statistical study and dynamical interpretation.
Oteo, J A; Ros, J
2007-09-01
The nature of the round-off errors that occur in the usual double precision computation of the logistic map is studied in detail. Different iterative regimes from the whole panoply of behaviors exhibited in the bifurcation diagram are examined, histograms of errors in trajectories given, and for the case of fully developed chaos an explicit formula is found. It is shown that the statistics of the largest double precision error as a function of the map parameter is characterized by jumps whose location is determined by certain boundary crossings in the bifurcation diagram. Both jumps and locations seem to present geometric convergence characterized by the two first Feigenbaum constants. Eventually, a comparison with Benford's law for the distribution of the leading digit of compilation of numbers is discussed. PMID:17930330
Statistical interpretation of transient current power-law decay in colloidal quantum dot arrays
NASA Astrophysics Data System (ADS)
Sibatov, R. T.
2011-08-01
A new statistical model of the charge transport in colloidal quantum dot arrays is proposed. It takes into account Coulomb blockade forbidding multiple occupancy of nanocrystals and the influence of energetic disorder of interdot space. The model explains power-law current transients and the presence of the memory effect. The fractional differential analogue of the Ohm law is found phenomenologically for nanocrystal arrays. The model combines ideas that were considered as conflicting by other authors: the Scher-Montroll idea about the power-law distribution of waiting times in localized states for disordered semiconductors is applied taking into account Coulomb blockade; Novikov's condition about the asymptotic power-law distribution of time intervals between successful current pulses in conduction channels is fulfilled; and the carrier injection blocking predicted by Ginger and Greenham (2000 J. Appl. Phys. 87 1361) takes place.
A Comprehensive Statistically-Based Method to Interpret Real-Time Flowing Measurements
Keita Yoshioka; Pinan Dawkrajai; Analis A. Romero; Ding Zhu; A. D. Hill; Larry W. Lake
2007-01-15
With the recent development of temperature measurement systems, continuous temperature profiles can be obtained with high precision. Small temperature changes can be detected by modern temperature measuring instruments such as fiber optic distributed temperature sensor (DTS) in intelligent completions and will potentially aid the diagnosis of downhole flow conditions. In vertical wells, since elevational geothermal changes make the wellbore temperature sensitive to the amount and the type of fluids produced, temperature logs can be used successfully to diagnose the downhole flow conditions. However, geothermal temperature changes along the wellbore being small for horizontal wells, interpretations of a temperature log become difficult. The primary temperature differences for each phase (oil, water, and gas) are caused by frictional effects. Therefore, in developing a thermal model for horizontal wellbore, subtle temperature changes must be accounted for. In this project, we have rigorously derived governing equations for a producing horizontal wellbore and developed a prediction model of the temperature and pressure by coupling the wellbore and reservoir equations. Also, we applied Ramey's model (1962) to the build section and used an energy balance to infer the temperature profile at the junction. The multilateral wellbore temperature model was applied to a wide range of cases at varying fluid thermal properties, absolute values of temperature and pressure, geothermal gradients, flow rates from each lateral, and the trajectories of each build section. With the prediction models developed, we present inversion studies of synthetic and field examples. These results are essential to identify water or gas entry, to guide flow control devices in intelligent completions, and to decide if reservoir stimulation is needed in particular horizontal sections. This study will complete and validate these inversion studies.
A Comprehensive Statistically-Based Method to Interpret Real-Time Flowing Measurements
Pinan Dawkrajai; Keita Yoshioka; Analis A. Romero; Ding Zhu; A.D. Hill; Larry W. Lake
2005-10-01
This project is motivated by the increasing use of distributed temperature sensors for real-time monitoring of complex wells (horizontal, multilateral and multi-branching wells) to infer the profiles of oil, gas, and water entry. Measured information can be used to interpret flow profiles along the wellbore including junction and build section. In this second project year, we have completed a forward model to predict temperature and pressure profiles in complex wells. As a comprehensive temperature model, we have developed an analytical reservoir flow model which takes into account Joule-Thomson effects in the near well vicinity and multiphase non-isothermal producing wellbore model, and couples those models accounting mass and heat transfer between them. For further inferences such as water coning or gas evaporation, we will need a numerical non-isothermal reservoir simulator, and unlike existing (thermal recovery, geothermal) simulators, it should capture subtle temperature change occurring in a normal production. We will show the results from the analytical coupled model (analytical reservoir solution coupled with numerical multi-segment well model) to infer the anomalous temperature or pressure profiles under various conditions, and the preliminary results from the numerical coupled reservoir model which solves full matrix including wellbore grids. We applied Ramey's model to the build section and used an enthalpy balance to infer the temperature profile at the junction. The multilateral wellbore temperature model was applied to a wide range of cases varying fluid thermal properties, absolute values of temperature and pressure, geothermal gradients, flow rates from each lateral, and the trajectories of each build section.
A COMPREHENSIVE STATISTICALLY-BASED METHOD TO INTERPRET REAL-TIME FLOWING MEASUREMENTS
Pinan Dawkrajai; Analis A. Romero; Keita Yoshioka; Ding Zhu; A.D. Hill; Larry W. Lake
2004-10-01
In this project, we are developing new methods for interpreting measurements in complex wells (horizontal, multilateral and multi-branching wells) to determine the profiles of oil, gas, and water entry. These methods are needed to take full advantage of ''smart'' well instrumentation, a technology that is rapidly evolving to provide the ability to continuously and permanently monitor downhole temperature, pressure, volumetric flow rate, and perhaps other fluid flow properties at many locations along a wellbore; and hence, to control and optimize well performance. In this first year, we have made considerable progress in the development of the forward model of temperature and pressure behavior in complex wells. In this period, we have progressed on three major parts of the forward problem of predicting the temperature and pressure behavior in complex wells. These three parts are the temperature and pressure behaviors in the reservoir near the wellbore, in the wellbore or laterals in the producing intervals, and in the build sections connecting the laterals, respectively. Many models exist to predict pressure behavior in reservoirs and wells, but these are almost always isothermal models. To predict temperature behavior we derived general mass, momentum, and energy balance equations for these parts of the complex well system. Analytical solutions for the reservoir and wellbore parts for certain special conditions show the magnitude of thermal effects that could occur. Our preliminary sensitivity analyses show that thermal effects caused by near-wellbore reservoir flow can cause temperature changes that are measurable with smart well technology. This is encouraging for the further development of the inverse model.
NASA Astrophysics Data System (ADS)
Bouzid, Mohamed; Sellaoui, Lotfi; Khalfaoui, Mohamed; Belmabrouk, Hafedh; Lamine, Abdelmottaleb Ben
2016-02-01
In this work, we studied the adsorption of ethanol on three types of activated carbon, namely parent Maxsorb III and two chemically modified activated carbons (H2-Maxsorb III and KOH-H2-Maxsorb III). This investigation has been conducted on the basis of the grand canonical formalism in statistical physics and on simplified assumptions. This led to three parameter equations describing the adsorption of ethanol onto the three types of activated carbon. There was a good correlation between experimental data and results obtained by the new proposed equation. The parameters characterizing the adsorption isotherm were the number of adsorbed molecules (s) per site n, the density of the receptor sites per unit mass of the adsorbent Nm, and the energetic parameter p1/2. They were estimated for the studied systems by a non linear least square regression. The results show that the ethanol molecules were adsorbed in perpendicular (or non parallel) position to the adsorbent surface. The magnitude of the calculated adsorption energies reveals that ethanol is physisorbed onto activated carbon. Both van der Waals and hydrogen interactions were involved in the adsorption process. The calculated values of the specific surface AS, proved that the three types of activated carbon have a highly microporous surface.
Statistical information of ASAR observations over wetland areas: An interaction model interpretation
NASA Astrophysics Data System (ADS)
Grings, F.; Salvia, M.; Karszenbaum, H.; Ferrazzoli, P.; Perna, P.; Barber, M.; Jacobo Berlles, J.
2010-01-01
This paper presents the results obtained after studying the relation between the statistical parameters that describe the backscattering distribution of junco marshes and their biophysical variables. The results are based on the texture analysis of a time series of Envisat ASAR C-band data (APP mode, V V +HH polarizations) acquired between October 2003 and January 2005 over the Lower Paraná River Delta, Argentina. The image power distributions were analyzed, and we show that the K distribution provides a good fitting of SAR data extracted from wetland observations for both polarizations. We also show that the estimated values of the order parameter of the K distribution can be explained using fieldwork and reasonable assumptions. In order to explore these results, we introduce a radiative transfer based interaction model to simulate the junco marsh σ0 distribution. After analyzing model simulations, we found evidence that the order parameter is related to the junco plant density distribution inside the junco marsh patch. It is concluded that the order parameter of the K distribution could be a useful parameter to estimate the junco plant density. This result is important for basin hydrodynamic modeling, since marsh plant density is the most important parameter to estimate marsh water conductance.
Hysteresis model and statistical interpretation of energy losses in non-oriented steels
NASA Astrophysics Data System (ADS)
Mănescu (Păltânea), Veronica; Păltânea, Gheorghe; Gavrilă, Horia
2016-04-01
In this paper the hysteresis energy losses in two non-oriented industrial steels (M400-65A and M800-65A) were determined, by means of an efficient classical Preisach model, which is based on the Pescetti-Biorci method for the identification of the Preisach density. The excess and the total energy losses were also determined, using a statistical framework, based on magnetic object theory. The hysteresis energy losses, in a non-oriented steel alloy, depend on the peak magnetic polarization and they can be computed using a Preisach model, due to the fact that in these materials there is a direct link between the elementary rectangular loops and the discontinuous character of the magnetization process (Barkhausen jumps). To determine the Preisach density it was necessary to measure the normal magnetization curve and the saturation hysteresis cycle. A system of equations was deduced and the Preisach density was calculated for a magnetic polarization of 1.5 T; then the hysteresis cycle was reconstructed. Using the same pattern for the Preisach distribution, it was computed the hysteresis cycle for 1 T. The classical losses were calculated using a well known formula and the excess energy losses were determined by means of the magnetic object theory. The total energy losses were mathematically reconstructed and compared with those, measured experimentally.
NASA Astrophysics Data System (ADS)
Lee, J.; Chang, H.
2001-12-01
In this research, we investigate the reciprocal influence between groundwater flow and its salinization occurred in two underground cavern sites, using major ion chemistry, PCA for chemical analysis data, and cross-correlation for various hydraulic data. The study areas are two underground LPG storage facilities constructed in South Sea coast, Yosu, and West Sea coastal regions, Pyeongtaek, Korea. Considerably high concentration of major cations and anions of groundwaters at both sites showed brackish or saline water types. In Yosu site, some great chemical difference of groundwater samples between rainy and dry season was caused by temporal intrusion of high-saline water into propane and butane cavern zone, but not in Pyeongtaek site. Cl/Br ratios and δ 18O- δ D distribution for tracing of salinization source water in both sites revealed that two kind of saline water (seawater and halite-dissolved solution) could influence the groundwater salinization in Yosu site, whereas only seawater intrusion could affect the groundwater chemistry of the observation wells in Pyeongtaek site. PCA performed by 8 and 10 chemical ions as statistical variables in both sites showed that intensive intrusion of seawater through butane cavern was occurred at Yosu site while seawater-groundwater mixing was observed at some observation wells located in the marginal part of Pyeongtaek site. Cross-correlation results revealed that the positive relationship between hydraulic head and cavern operating pressure was far more conspicuous at propane cavern zone in both sites (65 ~90% of correlation coefficients). According to the cross-correlation results of Yosu site, small change of head could provoke massive influx of halite-dissolved solution from surface through vertically developed fracture networks. However in Pyeongtaek site, the pressure-sensitive observation wells are not completely consistent with seawater-mixed wells, and the hydraulic change of heads at these wells related to the
Tsitouridou, Roxani; Papazova, Petia; Simeonova, Pavlina; Simeonov, Vasil
2013-01-01
The size distribution of aerosol particles (PM0.015-PM18) in relation to their soluble inorganic species and total water soluble organic compounds (WSOC) was investigated at an urban site of Thessaloniki, Northern Greece. The sampling period was from February to July 2007. The determined compounds were compared with mass concentrations of the PM fractions for nano (N: 0.015 < Dp < 0.06), ultrafine (UFP: 0.015 < Dp < 0.125), fine (FP: 0.015 < Dp < 2.0) and coarse particles (CP: 2.0 < Dp < 8.0) in order to perform mass closure of the water soluble content for the respective fractions. Electrolytes were the dominant species in all fractions (24-27%), followed by WSOC (16-23%). The water soluble inorganic and organic content was found to account for 53% of the nanoparticle, 48% of the ultrafine particle, 45% of the fine particle and 44% of the coarse particle mass. Correlations between the analyzed species were performed and the effect of local and long-range transported emissions was examined by wind direction and backward air mass trajectories. Multivariate statistical analysis (cluster analysis and principal components analysis) of the collected data was performed in order to reveal the specific data structure. Possible sources of air pollution were identified and an attempt is made to find patterns of similarity between the different sized aerosols and the seasons of monitoring. It was proven that several major latent factors are responsible for the data structure despite the size of the aerosols - mineral (soil) dust, sea sprays, secondary emissions, combustion sources and industrial impact. The seasonal separation proved to be not very specific. PMID:24007436
NASA Astrophysics Data System (ADS)
Dralle, D.; Karst, N.; Thompson, S. E.
2015-12-01
Multiple competing theories suggest that power law behavior governs the observed first-order dynamics of streamflow recessions - the important process by which catchments dry-out via the stream network, altering the availability of surface water resources and in-stream habitat. Frequently modeled as: dq/dt = -aqb, recessions typically exhibit a high degree of variability, even within a single catchment, as revealed by significant shifts in the values of "a" and "b" across recession events. One potential source of this variability lies in underlying, hard-to-observe fluctuations in how catchment water storage is partitioned amongst distinct storage elements, each having different discharge behaviors. Testing this and competing hypotheses with widely available streamflow timeseries, however, has been hindered by a power law scaling artifact that obscures meaningful covariation between the recession parameters, "a" and "b". Here we briefly outline a technique that removes this artifact, revealing intriguing new patterns in the joint distribution of recession parameters. Using long-term flow data from catchments in Northern California, we explore temporal variations, and find that the "a" parameter varies strongly with catchment wetness. Then we explore how the "b" parameter changes with "a", and find that measures of its variation are maximized at intermediate "a" values. We propose an interpretation of this pattern based on statistical mechanics, meaning "b" can be viewed as an indicator of the catchment "microstate" - i.e. the partitioning of storage - and "a" as a measure of the catchment macrostate (i.e. the total storage). In statistical mechanics, entropy (i.e. microstate variance, that is the variance of "b") is maximized for intermediate values of extensive variables (i.e. wetness, "a"), as observed in the recession data. This interpretation of "a" and "b" was supported by model runs using a multiple-reservoir catchment toy model, and lends support to the
An Easily Constructed Trigonal Prism Model.
ERIC Educational Resources Information Center
Yamana, Shukichi
1984-01-01
A model of a trigonal prism which is useful for teaching stereochemistry (especially of the neodymium enneahydrate ion), can be made easily by using a sealed, empty envelope. The steps necessary to accomplish this task are presented. (JN)
Huang, Ruili; Southall, Noel; Xia, Menghang; Cho, Ming-Hsuang; Jadhav, Ajit; Nguyen, Dac-Trung; Inglese, James; Tice, Raymond R.; Austin, Christopher P.
2009-01-01
In support of the U.S. Tox21 program, we have developed a simple and chemically intuitive model we call weighted feature significance (WFS) to predict the toxicological activity of compounds, based on the statistical enrichment of structural features in toxic compounds. We trained and tested the model on the following: (1) data from quantitative high–throughput screening cytotoxicity and caspase activation assays conducted at the National Institutes of Health Chemical Genomics Center, (2) data from Salmonella typhimurium reverse mutagenicity assays conducted by the U.S. National Toxicology Program, and (3) hepatotoxicity data published in the Registry of Toxic Effects of Chemical Substances. Enrichments of structural features in toxic compounds are evaluated for their statistical significance and compiled into a simple additive model of toxicity and then used to score new compounds for potential toxicity. The predictive power of the model for cytotoxicity was validated using an independent set of compounds from the U.S. Environmental Protection Agency tested also at the National Institutes of Health Chemical Genomics Center. We compared the performance of our WFS approach with classical classification methods such as Naive Bayesian clustering and support vector machines. In most test cases, WFS showed similar or slightly better predictive power, especially in the prediction of hepatotoxic compounds, where WFS appeared to have the best performance among the three methods. The new algorithm has the important advantages of simplicity, power, interpretability, and ease of implementation. PMID:19805409
Electronic modules easily separated from heat sink
NASA Technical Reports Server (NTRS)
1965-01-01
Metal heat sink and electronic modules bonded to a thermal bridge can be easily cleaved for removal of the modules for replacement or repair. A thin film of grease between a fluorocarbon polymer film on the metal heat sink and an adhesive film on the modules acts as the cleavage plane.
Links to sources of cancer-related statistics, including the Surveillance, Epidemiology and End Results (SEER) Program, SEER-Medicare datasets, cancer survivor prevalence data, and the Cancer Trends Progress Report.
ERIC Educational Resources Information Center
Barner, David; Snedeker, Jesse
2008-01-01
Four experiments investigated 4-year-olds' understanding of adjective-noun compositionality and their sensitivity to statistics when interpreting scalar adjectives. In Experiments 1 and 2, children selected "tall" and "short" items from 9 novel objects called "pimwits" (1-9 in. in height) or from this array plus 4 taller or shorter distractor…
Acquire CoOmmodities Easily Card
Soler, E. E.
1998-05-29
Acquire Commodities Easily Card (AceCard) provides an automated end-user method to distribute company credit card charges to internal charge numbers. AceCard will allow cardholders to record card purchases in an on-line order log, enter multiple account distributions per order that can be posted to the General Ledger, track orders, and receipt information, and provide a variety of cardholder and administrative reports. Please note: Customers must contact Ed Soler (423)-576-6151, Lockheed Martin Energy Systems, for help with the installation of the package. The fee for this installation help will be coordinated by the customer and Lockheed Martin and is in addition to cost of the package from ESTSC. Customers should contact Sandy Presley (423)-576-4708 for user help.
ACECARD. Acquire CoOmmodities Easily Card
Soler, E.E.
1996-09-01
Acquire Commodities Easily Card (AceCard) provides an automated end-user method to distribute company credit card charges to internal charge numbers. AceCard will allow cardholders to record card purchases in an on-line order log, enter multiple account distributions per order that can be posted to the General Ledger, track orders, and receipt information, and provide a variety of cardholder and administrative reports. Please note: Customers must contact Ed Soler (423)-576-6151, Lockheed Martin Energy Systems, for help with the installation of the package. The fee for this installation help will be coordinated by the customer and Lockheed Martin and is in addition to cost of the package from ESTSC. Customers should contact Sandy Presley (423)-576-4708 for user help.
Acquire CoOmmodities Easily Card
Energy Science and Technology Software Center (ESTSC)
1998-05-29
Acquire Commodities Easily Card (AceCard) provides an automated end-user method to distribute company credit card charges to internal charge numbers. AceCard will allow cardholders to record card purchases in an on-line order log, enter multiple account distributions per order that can be posted to the General Ledger, track orders, and receipt information, and provide a variety of cardholder and administrative reports. Please note: Customers must contact Ed Soler (423)-576-6151, Lockheed Martin Energy Systems, for helpmore » with the installation of the package. The fee for this installation help will be coordinated by the customer and Lockheed Martin and is in addition to cost of the package from ESTSC. Customers should contact Sandy Presley (423)-576-4708 for user help.« less
Quantum of area {Delta}A=8{pi}l{sub P}{sup 2} and a statistical interpretation of black hole entropy
Ropotenko, Kostiantyn
2010-08-15
In contrast to alternative values, the quantum of area {Delta}A=8{pi}l{sub P}{sup 2} does not follow from the usual statistical interpretation of black hole entropy; on the contrary, a statistical interpretation follows from it. This interpretation is based on the two concepts: nonadditivity of black hole entropy and Landau quantization. Using nonadditivity a microcanonical distribution for a black hole is found and it is shown that the statistical weight of a black hole should be proportional to its area. By analogy with conventional Landau quantization, it is shown that quantization of a black hole is nothing but the Landau quantization. The Landau levels of a black hole and their degeneracy are found. The degree of degeneracy is equal to the number of ways to distribute a patch of area 8{pi}l{sub P}{sup 2} over the horizon. Taking into account these results, it is argued that the black hole entropy should be of the form S{sub bh}=2{pi}{center_dot}{Delta}{Gamma}, where the number of microstates is {Delta}{Gamma}=A/8{pi}l{sub P}{sup 2}. The nature of the degrees of freedom responsible for black hole entropy is elucidated. The applications of the new interpretation are presented. The effect of noncommuting coordinates is discussed.
Easily Missed Fractures in the Lower Extremity.
Yu, Joseph S
2015-07-01
As long as radiography remains cheap and provides value in patient care, it will continue to be widely used as a front-line imaging technique. There are limitations to what a radiograph can depict, however. It is imperative to understand the limitations of radiography to avoid pitfalls owing to the overlap of numerous osseous structures. This article reminds the reader of the association between certain radiographic abnormalities and the anatomic relevance in the patient. Although interpretive errors occur in fast-paced, high-volume emergency settings, meticulous attention to changes in the cortex and medullary bone may help to keep errors to a minimum. PMID:26046508
Easily retrievable objects among the NEO population
NASA Astrophysics Data System (ADS)
García Yárnoz, D.; Sanchez, J. P.; McInnes, C. R.
2013-08-01
Asteroids and comets are of strategic importance for science in an effort to understand the formation, evolution and composition of the Solar System. Near-Earth Objects (NEOs) are of particular interest because of their accessibility from Earth, but also because of their speculated wealth of material resources. The exploitation of these resources has long been discussed as a means to lower the cost of future space endeavours. In this paper, we consider the currently known NEO population and define a family of so-called Easily Retrievable Objects (EROs), objects that can be transported from accessible heliocentric orbits into the Earth's neighbourhood at affordable costs. The asteroid retrieval transfers are sought from the continuum of low energy transfers enabled by the dynamics of invariant manifolds; specifically, the retrieval transfers target planar, vertical Lyapunov and halo orbit families associated with the collinear equilibrium points of the Sun-Earth Circular Restricted Three Body problem. The judicious use of these dynamical features provides the best opportunity to find extremely low energy Earth transfers for asteroid material. A catalogue of asteroid retrieval candidates is then presented. Despite the highly incomplete census of very small asteroids, the ERO catalogue can already be populated with 12 different objects retrievable with less than 500 m/s of Δ v. Moreover, the approach proposed represents a robust search and ranking methodology for future retrieval candidates that can be automatically applied to the growing survey of NEOs.
ERIC Educational Resources Information Center
Cruce, Ty M.
2009-01-01
This methodological note illustrates how a commonly used calculation of the Delta-p statistic is inappropriate for categorical independent variables, and this note provides users of logistic regression with a revised calculation of the Delta-p statistic that is more meaningful when studying the differences in the predicted probability of an…
NASA Astrophysics Data System (ADS)
Irving, J.; Knight, R.; Holliger, K.
2007-12-01
The distribution of subsurface water content can be an excellent indicator of soil texture, which strongly influences the unsaturated hydraulic properties controlling vadose zone contaminant transport. Characterizing the heterogeneity in subsurface water content for use in numerical transport models, however, is an extremely difficult task as conventional hydrological measurement techniques do not offer the combined high spatial resolution and coverage required for accurate simulations. A number of recent studies have shown that ground-penetrating radar (GPR) reflection images may contain useful information regarding the statistical structure of subsurface water content. Comparisons of the horizontal correlation structures of radar images and those obtained from water content measurements have shown that, in some cases, the statistical characteristics are remarkably similar. However, a key issue in these studies is that a reflection GPR image is primarily related to changes in subsurface water content, and not the water content distribution directly. As a result, statistics gathered on the reflection image have a very complex relationship with the statistics of the underlying water content distribution, this relationship depending on a number of factors including the frequency of the GPR antennas used. In this work, we attempt to address the above issue by posing the estimation of the statistical structure of water content from reflection GPR data as an inverse problem. Using a simple convolution model for a radar image, we first derive a forward model relating the statistical structure of a radar image to that of the underlying water content distribution. We then use this forward model to invert for the spatial statistics of the water content distribution, given the spatial statistics of the GPR reflection image as data. We do this within a framework of uncertainty, such that realistic statistical bounds can be placed on the information that is inferred. In other
Asfahani, Jamal
2014-02-01
Factor analysis technique is proposed in this research for interpreting the combination of nuclear well logging, including natural gamma ray, density and neutron-porosity, and the electrical well logging of long and short normal, in order to characterize the large extended basaltic areas in southern Syria. Kodana well logging data are used for testing and applying the proposed technique. The four resulting score logs enable to establish the lithological score cross-section of the studied well. The established cross-section clearly shows the distribution and the identification of four kinds of basalt which are hard massive basalt, hard basalt, pyroclastic basalt and the alteration basalt products, clay. The factor analysis technique is successfully applied on the Kodana well logging data in southern Syria, and can be used efficiently when several wells and huge well logging data with high number of variables are required to be interpreted. PMID:24296157
Pomeau, Yves; Louët, Sabine
2016-06-01
During the StatPhys Conference on 20th July 2016 in Lyon, France, Yves Pomeau and Daan Frenkel will be awarded the most important prize in the field of Statistical Mechanics: the 2016 Boltzmann Medal, named after the Austrian physicist and philosopher Ludwig Boltzmann. The award recognises Pomeau's key contributions to the Statistical Physics of non-equilibrium phenomena in general. And, in particular, for developing our modern understanding of fluid mechanics, instabilities, pattern formation and chaos. He is recognised as an outstanding theorist bridging disciplines from applied mathematics to statistical physics with a profound impact on the neighbouring fields of turbulence and mechanics. In the article Sabine Louët interviews Pomeau, who is an Editor for the European Physical Journal Special Topics. He shares his views and tells how he experienced the rise of Statistical Mechanics in the past few decades. He also touches upon the need to provide funding to people who have the rare ability to discover new things and ideas, and not just those who are good at filling in grant application forms. PMID:27349556
ERIC Educational Resources Information Center
Mickler, J. Ernest
This 60th annual report on collegiate enrollments in the United States is based on data received from 1,635 four-year institutions in the U.S., Puerto Rico, and the U.S. Territories. General notes, survey methodology notes, and a summary of findings are presented. Detailed statistical charts present institutional data on men and women students and…
Bruni, Aline Thaís; Velho, Jesus Antonio; Ferreira, Arthur Serra Lopes; Tasso, Maria Júlia; Ferrari, Raíssa Santos; Yoshida, Ricardo Luís; Dias, Marcos Salvador; Leite, Vitor Barbanti Pereira
2014-08-01
This study uses statistical techniques to evaluate reports on suicide scenes; it utilizes 80 reports from different locations in Brazil, randomly collected from both federal and state jurisdictions. We aimed to assess a heterogeneous group of cases in order to obtain an overall perspective of the problem. We evaluated variables regarding the characteristics of the crime scene, such as the detected traces (blood, instruments and clothes) that were found and we addressed the methodology employed by the experts. A qualitative approach using basic statistics revealed a wide distribution as to how the issue was addressed in the documents. We examined a quantitative approach involving an empirical equation and we used multivariate procedures to validate the quantitative methodology proposed for this empirical equation. The methodology successfully identified the main differences in the information presented in the reports, showing that there is no standardized method of analyzing evidences. PMID:25066170
Julià, Olga; Vidal-Mas, Jaume; Panikov, Nicolai S.; Vives-Rego, Josep
2010-01-01
We report a skew-Laplace statistical analysis of both flow cytometry scatters and cell size from microbial strains primarily grown in batch cultures, others in chemostat cultures and bacterial aquatic populations. Cytometry scatters best fit the skew-Laplace distribution while cell size as assessed by an electronic particle analyzer exhibited a moderate fitting. Unlike the cultures, the aquatic bacterial communities clearly do not fit to a skew-Laplace distribution. Due to its versatile nature, the skew-Laplace distribution approach offers an easy, efficient, and powerful tool for distribution of frequency analysis in tandem with the flow cytometric cell sorting. PMID:20592754
Julià, Olga; Vidal-Mas, Jaume; Panikov, Nicolai S; Vives-Rego, Josep
2010-01-01
We report a skew-Laplace statistical analysis of both flow cytometry scatters and cell size from microbial strains primarily grown in batch cultures, others in chemostat cultures and bacterial aquatic populations. Cytometry scatters best fit the skew-Laplace distribution while cell size as assessed by an electronic particle analyzer exhibited a moderate fitting. Unlike the cultures, the aquatic bacterial communities clearly do not fit to a skew-Laplace distribution. Due to its versatile nature, the skew-Laplace distribution approach offers an easy, efficient, and powerful tool for distribution of frequency analysis in tandem with the flow cytometric cell sorting. PMID:20592754
Nash, J. Thomas; Frishman, David
1983-01-01
Analytical results for 61 elements in 370 samples from the Ranger Mine area are reported. Most of the rocks come from drill core in the Ranger No. 1 and Ranger No. 3 deposits, but 20 samples are from unmineralized drill core more than 1 km from ore. Statistical tests show that the elements Mg, Fe, F, Be, Co, Li, Ni, Pb, Sc, Th, Ti, V, CI, As, Br, Au, Ce, Dy, La Sc, Eu, Tb, Yb, and Tb have positive association with uranium, and Si, Ca, Na, K, Sr, Ba, Ce, and Cs have negative association. For most lithologic subsets Mg, Fe, Li, Cr, Ni, Pb, V, Y, Sm, Sc, Eu, and Yb are significantly enriched in ore-bearing rocks, whereas Ca, Na, K, Sr, Ba, Mn, Ce, and Cs are significantly depleted. These results are consistent with petrographic observations on altered rocks. Lithogeochemistry can aid exploration, but for these rocks requires methods that are expensive and not amenable to routine use.
Kim, Kyoung-Ho; Yun, Seong-Taek; Choi, Byoung-Young; Chae, Gi-Tak; Joo, Yongsung; Kim, Kangjoo; Kim, Hyoung-Soo
2009-07-21
Hydrochemical and multivariate statistical interpretations of 16 physicochemical parameters of 45 groundwater samples from a riverside alluvial aquifer underneath an agricultural area in Osong, central Korea, were performed in this study to understand the spatial controls of nitrate concentrations in terms of biogeochemical processes occurring near oxbow lakes within a fluvial plain. Nitrate concentrations in groundwater showed a large variability from 0.1 to 190.6 mg/L (mean=35.0 mg/L) with significantly lower values near oxbow lakes. The evaluation of hydrochemical data indicated that the groundwater chemistry (especially, degree of nitrate contamination) is mainly controlled by two competing processes: 1) agricultural contamination and 2) redox processes. In addition, results of factorial kriging, consisting of two steps (i.e., co-regionalization and factor analysis), reliably showed a spatial control of the concentrations of nitrate and other redox-sensitive species; in particular, significant denitrification was observed restrictedly near oxbow lakes. The results of this study indicate that sub-oxic conditions in an alluvial groundwater system are developed geologically and geochemically in and near oxbow lakes, which can effectively enhance the natural attenuation of nitrate before the groundwater discharges to nearby streams. This study also demonstrates the usefulness of multivariate statistical analysis in groundwater study as a supplementary tool for interpretation of complex hydrochemical data sets. PMID:19524319
Fadda, Valeria; Maratea, Dario; Trippoli, Sabrina; Gatto, Roberta; De Rosa, Mauro; Marinai, Claudio
2014-01-01
Background: No equivalence analysis has yet been conducted on the effectiveness of biologics in rheumatoid arthritis. Equivalence testing has a specific scientific interest, but can also be useful for deciding whether acquisition tenders are feasible for the pharmacological agents being compared. Methods: Our search covered the literature up to August 2014. Our methodology was a combination of standard pairwise meta-analysis, Bayesian network meta-analysis and equivalence testing. The agents examined for their potential equivalence were etanercept, adalimumab, golimumab, certolizumab, and tocilizumab, each in combination with methotrexate (MTX). The reference treatment was MTX monotherapy. The endpoint was ACR50 achievement at 12 months. Odds ratio was the outcome measure. The equivalence margins were established by analyzing the statistical power data of the trials. Results: Our search identified seven randomized controlled trials (2846 patients). No study was retrieved for tocilizumab, and so only four biologics were evaluable. The equivalence range was set at odds ratio from 0.56 to 1.78. There were 10 head-to-head comparisons (4 direct, 6 indirect). Bayesian network meta-analysis estimated the odds ratio (with 90% credible intervals) for each of these comparisons. Between-trial heterogeneity was marked. According to our results, all credible intervals of the 10 comparisons were wide and none of them satisfied the equivalence criterion. A superiority finding was confirmed for the treatment with MTX plus adalimumab or certolizumab in comparison with MTX monotherapy, but not for the other two biologics. Conclusion: Our results indicate that these four biologics improved the rates of ACR50 achievement, but there was an evident between-study heterogeneity. The head-to-head indirect comparisons between individual biologics showed no significant difference, but failed to demonstrate the proof of no difference (i.e. equivalence). This body of evidence presently
NASA Astrophysics Data System (ADS)
Alpert, P. A.; Knopf, D. A.
2014-12-01
Ice nucleation is the initial step in forming mixed-phase and cirrus clouds, and is well established as an important influence on global climate. Laboratory studies investigate at which cloud relevant conditions of temperature (T) and relative humidity (RH) ice nucleation occurs and as a result, numerous fundamentally different ice nucleation descriptions have been proposed for implementation in cloud and climate models. We introduce a new immersion freezing model based on first principles of statistics to simulate individual droplet freezing requiring only three experimental parameters, which are the total number of droplets, the uncertainty of applied surface area per droplet, and the heterogeneous ice nucleation rate coefficient, Jhet, as a function as a function of T and water activity (aw), where in equilibrium RH=aw. Previous studies reporting frozen fractions (f) or Jhet for a droplet population are described by our model for mineral, inorganic, organic, and biological ice nuclei and different techniques including cold stage, oil-immersion, continuous flow diffusion chamber, flow tube, cloud chamber, acoustic levitation and wind levitation experiments. Taking advantage of the physically based parameterization of Jhet by Knopf and Alpert (Faraday Discuss., 165, 513-534, 2013), our model can predict immersion freezing for the entire atmospherically relevant range of T, RH, particle surface area, and time scales, even for conditions unattainable in a laboratory setting. Lastly, we present a rigorous experimental uncertainty analysis using a Monte Carlo method of laboratory derived Jhet and f. These results imply that classical nucleation theory is universal for immersion freezing. In combination with a aw based description of Jhet, this approach allows for a physically based and computational little demanding implementation in climate and cloud models.
Voltage controlled oscillator is easily aligned, has low phase noise
NASA Technical Reports Server (NTRS)
Sydnor, R. L.
1965-01-01
Voltage Controlled Oscillator /VCO/, represented by an equivalent RF circuit, is easily adjusted for optimum performance by varying the circuit parameter. It contains a crystal drive level which is also easily adjusted to obtain minimum phase noise.
Dziurkowska, Ewelina; Wesolowski, Marek
2015-01-01
Multivariate statistical analysis is widely used in medical studies as a profitable tool facilitating diagnosis of some diseases, for instance, cancer, allergy, pneumonia, or Alzheimer's and psychiatric diseases. Taking this in consideration, the aim of this study was to use two multivariate techniques, hierarchical cluster analysis (HCA) and principal component analysis (PCA), to disclose the relationship between the drugs used in the therapy of major depressive disorder and the salivary cortisol level and the period of hospitalization. The cortisol contents in saliva of depressed women were quantified by HPLC with UV detection day-to-day during the whole period of hospitalization. A data set with 16 variables (e.g., the patients' age, multiplicity and period of hospitalization, initial and final cortisol level, highest and lowest hormone level, mean contents, and medians) characterizing 97 subjects was used for HCA and PCA calculations. Multivariate statistical analysis reveals that various groups of antidepressants affect at the varying degree the salivary cortisol level. The SSRIs, SNRIs, and the polypragmasy reduce most effectively the hormone secretion. Thus, both unsupervised pattern recognition methods, HCA and PCA, can be used as complementary tools for interpretation of the results obtained by laboratory diagnostic methods. PMID:26380376
Teaching the Assessment of Normality Using Large Easily-Generated Real Data Sets
ERIC Educational Resources Information Center
Kulp, Christopher W.; Sprechini, Gene D.
2016-01-01
A classroom activity is presented, which can be used in teaching students statistics with an easily generated, large, real world data set. The activity consists of analyzing a video recording of an object. The colour data of the recorded object can then be used as a data set to explore variation in the data using graphs including histograms,…
Guyonvarch, Estelle; Ramin, Elham; Kulahci, Murat; Plósz, Benedek Gy
2015-10-15
The present study aims at using statistically designed computational fluid dynamics (CFD) simulations as numerical experiments for the identification of one-dimensional (1-D) advection-dispersion models - computationally light tools, used e.g., as sub-models in systems analysis. The objective is to develop a new 1-D framework, referred to as interpreted CFD (iCFD) models, in which statistical meta-models are used to calculate the pseudo-dispersion coefficient (D) as a function of design and flow boundary conditions. The method - presented in a straightforward and transparent way - is illustrated using the example of a circular secondary settling tank (SST). First, the significant design and flow factors are screened out by applying the statistical method of two-level fractional factorial design of experiments. Second, based on the number of significant factors identified through the factor screening study and system understanding, 50 different sets of design and flow conditions are selected using Latin Hypercube Sampling (LHS). The boundary condition sets are imposed on a 2-D axi-symmetrical CFD simulation model of the SST. In the framework, to degenerate the 2-D model structure, CFD model outputs are approximated by the 1-D model through the calibration of three different model structures for D. Correlation equations for the D parameter then are identified as a function of the selected design and flow boundary conditions (meta-models), and their accuracy is evaluated against D values estimated in each numerical experiment. The evaluation and validation of the iCFD model structure is carried out using scenario simulation results obtained with parameters sampled from the corners of the LHS experimental region. For the studied SST, additional iCFD model development was carried out in terms of (i) assessing different density current sub-models; (ii) implementation of a combined flocculation, hindered, transient and compression settling velocity function; and (iii
Easily constructed mini-sextant demonstrates optical principles
NASA Astrophysics Data System (ADS)
Nenninger, Garet G.
2000-04-01
An easily constructed optical instrument for measuring the angle between the Sun and the horizon is described. The miniature sextant relies on multiple reflections to produce multiple images of the sun at fixed angles away from the true Sun.
Description of the Experimental Avionics Systems Integration Laboratory (EASILY)
NASA Technical Reports Server (NTRS)
Outlaw, Bruce K. E.
1994-01-01
The Experimental Avionics Systems Integration Laboratory (EASILY) is a comprehensive facility used for development, integration, and preflight validation of hardware and software systems for the Terminal Area Productivity (TAP) Program's Transport Systems Research Vehicle (TSRV) experimental transport aircraft. This report describes the history, capabilities, and subsystems of EASILY. A functional description of the many subsystems is provided to give potential users the necessary knowledge of the capabilities of this facility.
Micromanipulation tool is easily adapted to many uses
NASA Technical Reports Server (NTRS)
Shlichta, P. J.
1967-01-01
A special micromanipulation tool equipped with a plunger mounted in a small tube can be easily adapted to such work operations as cutting, precision clamping, and spot welding of microscopic filaments or other parts. This tool is valuable where extreme steadiness of high magnification is required.
Modular thermoelectric cell is easily packaged in various arrays
NASA Technical Reports Server (NTRS)
Epstein, J.
1965-01-01
Modular thermoelectric cells are easily packaged in various arrays to form power supplies and have desirable voltage and current output characteristics. The cells employ two pairs of thermoelectric elements, each pair being connected in parallel between two sets of aluminum plates. They can be used as solar energy conversion devices.
Easily disassembled electrical connector for high voltage, high frequency connections
Milner, J.R.
1994-05-10
An easily accessible electrical connector capable of rapid assembly and disassembly is described wherein a wide metal conductor sheet may be evenly contacted over the entire width of the conductor sheet by opposing surfaces on the connector which provide an even clamping pressure against opposite surfaces of the metal conductor sheet using a single threaded actuating screw. 13 figures.
Easily disassembled electrical connector for high voltage, high frequency connections
Milner, Joseph R.
1994-01-01
An easily accessible electrical connector capable of rapid assembly and disassembly wherein a wide metal conductor sheet may be evenly contacted over the entire width of the conductor sheet by opposing surfaces on the connector which provide an even clamping pressure against opposite surfaces of the metal conductor sheet using a single threaded actuating screw.
The advent of new higher throughput analytical instrumentation has put a strain on interpreting and explaining the results from complex studies. Contemporary human, environmental, and biomonitoring data sets are comprised of tens or hundreds of analytes, multiple repeat measures...
A method for easily customizable gradient gel electrophoresis.
Miller, Andrew J; Roman, Brandon; Norstrom, Eric
2016-09-15
Gradient polyacrylamide gel electrophoresis is a powerful tool for the resolution of polypeptides by relative mobility. Here, we present a simplified method for generating polyacrylamide gradient gels for routine analysis without the need for specialized mixing equipment. The method allows for easily customizable gradients which can be optimized for specific polypeptide resolution requirements. Moreover, the method eliminates the possibility of buffer cross contamination in mixing equipment, and the time and resources saved with this method in place of traditional gradient mixing, or the purchase of pre-cast gels, are noteworthy given the frequency with which many labs use gradient gel SDS-PAGE. PMID:27393767
Easily Transported CCD Systems for Use in Astronomy Labs
NASA Astrophysics Data System (ADS)
Meisel, D.
1992-12-01
Relatively inexpensive CCD cameras and portable computers are now easily obtained as commercially available products. I will describe a prototype system that can be used by introductory astronomy students, even urban enviroments, to obtain useful observations of the night sky. It is based on the ST-4 CCDs made by Santa Barbara Instruments Group and Macintosh Powerbook145 computers. Students take outdoor images directly from the college campus, bring the exposures back into the lab and download the images into our networked server. These stored images can then be processed (at a later time) using a variety of image processing programs including a new astronomical version of the popular "freeware" NIH Image package that is currently under development at Geneseo. The prototype of this system will be demonstrated and available for hands-on use during the meeting. This work is supported by NSF ILI Demonstration Grant USE9250493 and Grants from SUNY-GENESEO.
Easily installable behavioral monitoring system with electric field sensor.
Tsukamoto, Sosuke; Machida, Yuichiro; Kameda, Noriyuki; Hoshino, Hiroshi; Tamura, Toshiyo
2007-01-01
This paper describes a wireless behavioral monitoring system equipped with an electric field sensor. The sensor unit was designed to obtain information regarding the usage of home electric appliances such as the television, microwave oven, coffee maker, etc. by measuring the electric field surrounding them. It is assumed that these usage statistics could provide information regarding the indoor behavior of a subject. Since the sensor can be used by simply attaching it to an appliance and does not require any wiring for its installation, this system can be temporarily installed in any ordinary house. A simple interface for selecting the threshold value of appliances' power on/off states was introduced. The experimental results reveal that the proposed system can be installed by individuals in their residences in a short time and the usage statistics of home appliances can be gathered. PMID:18002891
ERIC Educational Resources Information Center
BARNETT, F.C.; SAW, J.G.
A WORKING MODEL CAPABLE OF RANKING INDIVIDUALS IN A RANDOM SAMPLE FROM A MULTIVARIATE POPULATION BY SOME CRITERION OF INTEREST WAS DEVELOPED. THE MULTIPLE CORRELATION COEFFICIENT OF RANKS WITH MEASURED VARIATES AS A STATISTIC IN TESTING WHETHER RANKS ARE ASSOCIATED WITH MEASUREMENTS WAS EMPLOYED AND DUBBED "QUASI-RANK MULTIPLE CORRELATION…
ERIC Educational Resources Information Center
BARGMANN, ROLF E.
THE STUDIES EMBODIED IN THIS REPORT PROPOSE SOME STATISTICAL METHODS OF ORDERING AND ATTAINING RELEVANCY TO HELP THE EDUCATIONAL RESEARCHER CHOOSE AMONG SUCH VARIABLES AS TESTS AND BEHAVIOR RATINGS. CONSTRUCTION OF A MODEL FOR THE ANALYSIS OF CONTINGENCY TABLES, DETERMINATION OF THE MOST APPROPRIATE ORDERING PRINCIPLE IN STEP-DOWN ANALYSIS FOR THE…
Design of easily testable and reconfigurable systolic arrays
Kim, J.H.
1987-01-01
Systolic arrays are considered to be preferred architectures for executing linear algebraic operations. In this thesis, easily testable and reconfigurable (ETAR) systolic arrays are studied to achieve the yield enhancement. New 2-D systolic arrays that lend themselves to easy reconfiguration as well as efficient implementations of algorithms are proposed. The 2-D bidirectional and unidirectional systolic arrays proposed are often better architectures than the rectangular and hexagonal systolic arrays proposed earlier, if one considers area, time and reconfigurability. Methods to design linear and 2-D ETAR systolic arrays are proposed. Procedures to design linear and 2-D unidirectional and bidirectional systolic arrays are given. The main feature of the proposed designs is that the COMUs of the PEs in the linear array can all be tested simultaneously. Another feature is that the throughputs of the reconfigured linear unidirectional as well as bidirectional arrays can remain to be equal to those of the fault-free linear arrays. A reconfiguration algorithm for 2-D systolic arrays is also proposed.
A highly versatile and easily configurable system for plant electrophysiology.
Gunsé, Benet; Poschenrieder, Charlotte; Rankl, Simone; Schröeder, Peter; Rodrigo-Moreno, Ana; Barceló, Juan
2016-01-01
In this study we present a highly versatile and easily configurable system for measuring plant electrophysiological parameters and ionic flow rates, connected to a computer-controlled highly accurate positioning device. The modular software used allows easy customizable configurations for the measurement of electrophysiological parameters. Both the operational tests and the experiments already performed have been fully successful and rendered a low noise and highly stable signal. Assembly, programming and configuration examples are discussed. The system is a powerful technique that not only gives precise measuring of plant electrophysiological status, but also allows easy development of ad hoc configurations that are not constrained to plant studies. •We developed a highly modular system for electrophysiology measurements that can be used either in organs or cells and performs either steady or dynamic intra- and extracellular measurements that takes advantage of the easiness of visual object-oriented programming.•High precision accuracy in data acquisition under electrical noisy environments that allows it to run even in a laboratory close to electrical equipment that produce electrical noise.•The system makes an improvement of the currently used systems for monitoring and controlling high precision measurements and micromanipulation systems providing an open and customizable environment for multiple experimental needs. PMID:27298766
Triazolophthalazines: Easily Accessible Compounds with Potent Antitubercular Activity.
Veau, Damien; Krykun, Serhii; Mori, Giorgia; Orena, Beatrice S; Pasca, Maria R; Frongia, Céline; Lobjois, Valérie; Chassaing, Stefan; Lherbet, Christian; Baltas, Michel
2016-05-19
Tuberculosis (TB) remains one of the major causes of death worldwide, in particular because of the emergence of multidrug-resistant TB. Herein we explored the potential of an alternative class of molecules as anti-TB agents. Thus, a series of novel 3-substituted triazolophthalazines was quickly and easily prepared from commercial hydralazine hydrochloride as starting material and were further evaluated for their antimycobacterial activities and cytotoxicities. Four of the synthesized compounds were found to effectively inhibit the Mycobacterium tuberculosis (M.tb) H37 Rv strain with minimum inhibitory concentration (MIC) values <10 μg mL(-1) , whereas no compounds displayed cytotoxicity against HCT116 human cell lines (IC50 >100 μm). More remarkably, the most potent compounds proved to be active to a similar extent against various multidrug-resistant M.tb strains, thus uncovering a mode of action distinct from that of standard antitubercular agents. Overall, their ease of preparation, combined with their attractive antimycobacterial activities, make such triazolophthalazine-based derivatives promising leads for further development. PMID:27097919
Metview and VAPOR: Exploring ECMWF forecasts easily in four dimensions
NASA Astrophysics Data System (ADS)
Siemen, Stephan; Kertesz, Sandor; Carver, Glenn
2014-05-01
The European Centre for Medium-Range Weather Forecasts (ECMWF) is an international organisation providing its member states and co-operating states with forecasts in the medium time range of up to 15 days as well as other forcasts and analysis. As part of its mission, ECMWF generates an increasing number of forecast data products for its users. To support the work of forecasters and researchers and to let them make best use of ECMWF forecasts, the Centre also provides tools and interfaces to visualise their products. This allows users to make use of and explore forecasts without having to transfer large amounts of raw data. This is especially true for products based on ECMWF's 50 member ensemble forecast. Users can choose to explore ECMWF's forecasts from the web or through visualisation tools installed locally or at ECMWF. ECMWF also develops in co-operation with INPE, Brazil, the Metview meteorological workstation and batch system. Metview enables users to easily analyse and visualise forecasts, and is routinely used by scientists and forecasters at ECMWF and other institutions. While Metview offers high quality visualisation in two-dimensional plots and animations, it uses external tools to visualise data in four dimensions. VAPOR is the Visualization and Analysis Platform for Ocean, Atmosphere, and Solar Researchers. VAPOR provides an interactive 3D visualisation environment that runs on most UNIX and Windows systems equipped with modern 3D graphics cards. VAPOR development is led by the National Center for Atmospheric Research's Scientific Computing Division in collaboration with U.C. Davis and Ohio State University. In this paper we will give an overview of how users, with Metview and access to ECMWF's archive, can visualise forecast data in four dimensions within VAPOR. The process of preparing the data in Metview is the key step and described in detail. The benefits to researchers are highlighted with a case study analysing a given weather scenario.
NASA Technical Reports Server (NTRS)
Feiveson, Alan H.; Foy, Millennia; Ploutz-Snyder, Robert; Fiedler, James
2014-01-01
Do you have elevated p-values? Is the data analysis process getting you down? Do you experience anxiety when you need to respond to criticism of statistical methods in your manuscript? You may be suffering from Insufficient Statistical Support Syndrome (ISSS). For symptomatic relief of ISSS, come for a free consultation with JSC biostatisticians at our help desk during the poster sessions at the HRP Investigators Workshop. Get answers to common questions about sample size, missing data, multiple testing, when to trust the results of your analyses and more. Side effects may include sudden loss of statistics anxiety, improved interpretation of your data, and increased confidence in your results.
Bogen, K; Hamilton, T F; Brown, T A; Martinelli, R E; Marchetti, A A; Kehl, S R; Langston, R G
2007-05-01
We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from <1 to 8 {micro}Bq per day and are well below action levels established under the latest Department regulation 10 CFR 835 in the United States for in vitro bioassay monitoring of {sup 239}Pu. However, our statistical analyses show that urinary excretion of plutonium-239 ({sup 239}Pu) from both cohort groups is significantly positively associated with volunteer age, especially for the resident population living on Enewetak Atoll. Urinary excretion of {sup 239}Pu from the Enewetak cohort was also found to be positively associated with estimates of cumulative exposure to worldwide fallout. Consequently, the age-related trends in urinary excretion of plutonium from Marshallese populations can be described by either a long-term component from residual systemic burdens acquired from previous exposures to worldwide fallout or a prompt (and eventual long-term) component acquired from low-level systemic intakes of plutonium associated with resettlement of the northern Marshall Islands, or some combination of both.
Making large amounts of meteorological plots easily accessible to users
NASA Astrophysics Data System (ADS)
Lamy-Thepaut, Sylvie; Siemen, Stephan; Sahin, Cihan; Raoult, Baudouin
2015-04-01
implementation, It presents the user's products in a single interface with fast access to the original product, and possibilities of synchronous animations between them. But its functionalities are being extended to give users the freedom to collect not only ecCharts's 2D maps and graphs, but also other ECMWF Web products such as monthly and seasonal products, scores, and observation monitoring. The dashboard will play a key role to help the user to interpret the large amount of information that ECMWF is providing. This talk will present examples of how the new user interface can organise complex meteorological maps and graphs and show the new possibilities users have gained by using the web as a medium.
Spirakis, C.S.; Pierson, C.T.; Santos, E.S.; Fishman, N.S.
1983-01-01
Statistical treatment of analytical data from 106 samples of uranium-mineralized and unmineralized or weakly mineralized rocks of the Morrison Formation from the northeastern part of the Church Rock area of the Grants uranium region indicates that along with uranium, the deposits in the northeast Church Rock area are enriched in barium, sulfur, sodium, vanadium and equivalent uranium. Selenium and molybdenum are sporadically enriched in the deposits and calcium, manganese, strontium, and yttrium are depleted. Unlike the primary deposits of the San Juan Basin, the deposits in the northeast part of the Church Rock area contain little organic carbon and several elements that are characteristically enriched in the primary deposits are not enriched or are enriched to a much lesser degree in the Church Rock deposits. The suite of elements associated with the deposits in the northeast part of the Church Rock area is also different from the suite of elements associated with the redistributed deposits in the Ambrosia Lake district. This suggests that the genesis of the Church Rock deposits is different, at least in part, from the genesis of the primary deposits of the San Juan Basin or the redistributed deposits at Ambrosia Lake.
NASA Astrophysics Data System (ADS)
Tema, E.; Zanella, E.; Pavón-Carrasco, F. J.; Kondopoulou, D.; Pavlides, S.
2015-10-01
We present the results of palaeomagnetic analysis on Late Bronge Age pottery from Santorini carried out in order to estimate the thermal effect of the Minoan eruption on the pre-Minoan habitation level. A total of 170 specimens from 108 ceramic fragments have been studied. The ceramics were collected from the surface of the pre-Minoan palaeosol at six different sites, including also samples from the Akrotiri archaeological site. The deposition temperatures of the first pyroclastic products have been estimated by the maximum overlap of the re-heating temperature intervals given by the individual fragments at site level. A new statistical elaboration of the temperature data has also been proposed, calculating at 95 per cent of probability the re-heating temperatures at each site. The obtained results show that the precursor tephra layer and the first pumice fall of the eruption were hot enough to re-heat the underlying ceramics at temperatures 160-230 °C in the non-inhabited sites while the temperatures recorded inside the Akrotiri village are slightly lower, varying from 130 to 200 °C. The decrease of the temperatures registered in the human settlements suggests that there was some interaction between the buildings and the pumice fallout deposits while probably the buildings debris layer caused by the preceding and syn-eruption earthquakes has also contributed to the decrease of the recorded re-heating temperatures.
Linda Stetzenbach; Lauren Nemnich; Davor Novosel
2009-08-31
Three independent tasks had been performed (Stetzenbach 2008, Stetzenbach 2008b, Stetzenbach 2009) to measure a variety of parameters in normative buildings across the United States. For each of these tasks 10 buildings were selected as normative indoor environments. Task 1 focused on office buildings, Task 13 focused on public schools, and Task 0606 focused on high performance buildings. To perform this task it was necessary to restructure the database for the Indoor Environmental Quality (IEQ) data and the Sound measurement as several issues were identified and resolved prior to and during the transfer of these data sets into SPSS. During overview discussions with the statistician utilized in this task it was determined that because the selection of indoor zones (1-6) was independently selected within each task; zones were not related by location across tasks. Therefore, no comparison would be valid across zones for the 30 buildings so the by location (zone) data were limited to three analysis sets of the buildings within each task. In addition, differences in collection procedures for lighting were used in Task 0606 as compared to Tasks 01 & 13 to improve sample collection. Therefore, these data sets could not be merged and compared so effects by-day data were run separately for Task 0606 and only Task 01 & 13 data were merged. Results of the statistical analysis of the IEQ parameters show statistically significant differences were found among days and zones for all tasks, although no differences were found by-day for Draft Rate data from Task 0606 (p>0.05). Thursday measurements of IEQ parameters were significantly different from Tuesday, and most Wednesday measures for all variables of Tasks 1 & 13. Data for all three days appeared to vary for Operative Temperature, whereas only Tuesday and Thursday differed for Draft Rate 1m. Although no Draft Rate measures within Task 0606 were found to significantly differ by-day, Temperature measurements for Tuesday and
NASA Astrophysics Data System (ADS)
Xu, C.; Shyu, J. B. H.; Xu, X.-W.
2014-02-01
The 12 January 2010 Port-au-Prince, Haiti, earthquake (Mw 7.0) triggered tens of thousands of landslides. The purpose of this study is to investigate the correlations of the occurrence of landslides and their erosion thicknesses with topographic factors, seismic parameters, and their distance from roads. A total of 30 828 landslides triggered by the earthquake covered a total area of 15.736 km2, distributed in an area more than 3000 km2, and the volume of landslide accumulation materials is estimated to be about 29 700 000 m3. These landslides are of various types, mostly belonging to shallow disrupted landslides and rock falls, but also include coherent deep-seated landslides and rock slides. These landslides were delineated using pre- and post-earthquake high-resolutions satellite images. Spatial distribution maps and contour maps of landslide number density, landslide area percentage, and landslide erosion thickness were constructed in order to analyze the spatial distribution patterns of co-seismic landslides. Statistics of size distribution and morphometric parameters of co-seismic landslides were carried out and were compared with other earthquake events in the world. Four proxies of co-seismic landslide abundance, including landslides centroid number density (LCND), landslide top number density (LTND), landslide area percentage (LAP), and landslide erosion thickness (LET) were used to correlate co-seismic landslides with various landslide controlling parameters. These controlling parameters include elevation, slope angle, slope aspect, slope curvature, topographic position, distance from drainages, lithology, distance from the epicenter, distance from the Enriquillo-Plantain Garden fault, distance along the fault, and peak ground acceleration (PGA). A comparison of these impact parameters on co-seismic landslides shows that slope angle is the strongest impact parameter on co-seismic landslide occurrence. Our co-seismic landslide inventory is much more
NASA Astrophysics Data System (ADS)
Xu, C.; Shyu, J. B. H.; Xu, X.
2014-07-01
The 12 January 2010 Port-au-Prince, Haiti, earthquake (Mw= 7.0) triggered tens of thousands of landslides. The purpose of this study is to investigate the correlations of the occurrence of landslides and the thicknesses of their erosion with topographic, geologic, and seismic parameters. A total of 30 828 landslides triggered by the earthquake covered a total area of 15.736 km2, distributed in an area more than 3000 km2, and the volume of landslide accumulation materials is estimated to be about 29 700 000 m3. These landslides are of various types, mostly belonging to shallow disrupted landslides and rock falls, but also include coherent deep-seated landslides and rock slides. These landslides were delineated using pre- and post-earthquake high-resolution satellite images. Spatial distribution maps and contour maps of landslide number density, landslide area percentage, and landslide erosion thickness were constructed in order to analyze the spatial distribution patterns of co-seismic landslides. Statistics of size distribution and morphometric parameters of co-seismic landslides were carried out and were compared with other earthquake events in the world. Four proxies of co-seismic landslide abundance, including landslides centroid number density (LCND), landslide top number density (LTND), landslide area percentage (LAP), and landslide erosion thickness (LET) were used to correlate co-seismic landslides with various environmental parameters. These parameters include elevation, slope angle, slope aspect, slope curvature, topographic position, distance from drainages, lithology, distance from the epicenter, distance from the Enriquillo-Plantain Garden fault, distance along the fault, and peak ground acceleration (PGA). A comparison of these impact parameters on co-seismic landslides shows that slope angle is the strongest impact parameter on co-seismic landslide occurrence. Our co-seismic landslide inventory is much more detailed than other inventories in several
Tsukamoto, S; Hoshino, H; Tamura, T
2008-01-01
This paper describes an indoor behavioral monitoring system for improving the quality of life in ordinary houses. It employs a device that uses weak radio waves for transmitting the obtained data and it is designed such that it can be installed by a user without requiring any technical knowledge or extra constructions. This study focuses on determining the usage statistics of home electric appliances by using an electromagnetic field sensor as a detection device. The usage of the home appliances is determined by measuring the electromagnetic field that can be observed in an area near the appliance. It is assumed that these usage statistics could provide information regarding the indoor behavior of a subject. Since the sensor is not direction sensitive and does not require precise positioning and wiring, it can be easily installed in ordinary houses by the end users. For evaluating the practicability of the sensor unit, several simple tests have been performed. The results indicate that the proposed system could be useful for collecting the usage statistics of home appliances. PMID:19415135
ERIC Educational Resources Information Center
DeHaan, Frank, Ed.
1977-01-01
Describes an interpretative experiment involving the application of symmetry and temperature-dependent proton and fluorine nmr spectroscopy to the solution of structural and kinetic problems in coordination chemistry. (MLH)
ERIC Educational Resources Information Center
Pankhurst, Anne
1994-01-01
This paper examines some of the problems associated with interpreting metonymy, a figure of speech in which an attribute or commonly associated feature is used to name or designate something. After defining metonymy and outlining the principles of metonymy, the paper explains the differences between metonymy, synecdoche, and metaphor. It is…
ERIC Educational Resources Information Center
Kothe, Elsa Lenz; Berard, Marie-France
2013-01-01
Utilizing a/r/tographic methodology to interrogate interpretive acts in museums, multiple areas of inquiry are raised in this paper, including: which knowledge is assigned the greatest value when preparing a gallery talk; what lies outside of disciplinary knowledge; how invitations to participate invite and disinvite in the same gesture; and what…
ERIC Educational Resources Information Center
Munsart, Craig A.
1993-01-01
Presents an activity that allows students to experience the type of discovery process that paleontologists necessarily followed during the early dinosaur explorations. Students are read parts of a story taken from the "American Journal of Science" and interpret the evidence leading to the discovery of Triceratops and Stegosaurus. (PR)
CAinterprTools: An R package to help interpreting Correspondence Analysis' results
NASA Astrophysics Data System (ADS)
Alberti, Gianmarco
2015-09-01
Correspondence Analysis (CA) is a statistical exploratory technique frequently used in many research fields to graphically visualize the structure of contingency tables. Many programs, both commercial and free, perform CA but none of them as yet provides a visual aid to the interpretation of the results. The 'CAinterprTools' package, designed to be used in the free R statistical environment, aims at filling that gap. A novel-to-medium R user has been considered as target. 15 commands enable to easily obtain charts that help (and are relevant to) the interpretation of the CA's results, freeing the user from the need to inspect and scrutinize tabular CA outputs, and to look up values and statistics on which further calculations are necessary. The package also implements tests to assess the significance of the input table's total inertia and individual dimensions.
A flexible, interpretable framework for assessing sensitivity to unmeasured confounding.
Dorie, Vincent; Harada, Masataka; Carnegie, Nicole Bohme; Hill, Jennifer
2016-09-10
When estimating causal effects, unmeasured confounding and model misspecification are both potential sources of bias. We propose a method to simultaneously address both issues in the form of a semi-parametric sensitivity analysis. In particular, our approach incorporates Bayesian Additive Regression Trees into a two-parameter sensitivity analysis strategy that assesses sensitivity of posterior distributions of treatment effects to choices of sensitivity parameters. This results in an easily interpretable framework for testing for the impact of an unmeasured confounder that also limits the number of modeling assumptions. We evaluate our approach in a large-scale simulation setting and with high blood pressure data taken from the Third National Health and Nutrition Examination Survey. The model is implemented as open-source software, integrated into the treatSens package for the R statistical programming language. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. PMID:27139250
Reeve, Joanne
2010-01-01
Patient-centredness is a core value of general practice; it is defined as the interpersonal processes that support the holistic care of individuals. To date, efforts to demonstrate their relationship to patient outcomes have been disappointing, whilst some studies suggest values may be more rhetoric than reality. Contextual issues influence the quality of patient-centred consultations, impacting on outcomes. The legitimate use of knowledge, or evidence, is a defining aspect of modern practice, and has implications for patient-centredness. Based on a critical review of the literature, on my own empirical research, and on reflections from my clinical practice, I critique current models of the use of knowledge in supporting individualised care. Evidence-Based Medicine (EBM), and its implementation within health policy as Scientific Bureaucratic Medicine (SBM), define best evidence in terms of an epistemological emphasis on scientific knowledge over clinical experience. It provides objective knowledge of disease, including quantitative estimates of the certainty of that knowledge. Whilst arguably appropriate for secondary care, involving episodic care of selected populations referred in for specialist diagnosis and treatment of disease, application to general practice can be questioned given the complex, dynamic and uncertain nature of much of the illness that is treated. I propose that general practice is better described by a model of Interpretive Medicine (IM): the critical, thoughtful, professional use of an appropriate range of knowledges in the dynamic, shared exploration and interpretation of individual illness experience, in order to support the creative capacity of individuals in maintaining their daily lives. Whilst the generation of interpreted knowledge is an essential part of daily general practice, the profession does not have an adequate framework by which this activity can be externally judged to have been done well. Drawing on theory related to the
SLAR image interpretation keys for geographic analysis
NASA Technical Reports Server (NTRS)
Coiner, J. C.
1972-01-01
A means for side-looking airborne radar (SLAR) imagery to become a more widely used data source in geoscience and agriculture is suggested by providing interpretation keys as an easily implemented interpretation model. Interpretation problems faced by the researcher wishing to employ SLAR are specifically described, and the use of various types of image interpretation keys to overcome these problems is suggested. With examples drawn from agriculture and vegetation mapping, direct and associate dichotomous image interpretation keys are discussed and methods of constructing keys are outlined. Initial testing of the keys, key-based automated decision rules, and the role of the keys in an information system for agriculture are developed.
NASA Astrophysics Data System (ADS)
Oldroyd, H. J.; Higgins, C. W.; Huwald, H.; Selker, J. S.; Parlange, M. B.
2011-12-01
Thermal diffusivity of snow is an important physical property associated with key hydrological phenomena such as snow melt and heat and water vapor exchange with the atmosphere. These phenomena have broad implications in studies of climate and heat and water budgets on many scales. However, direct measurements of snow thermal diffusivity require coupled point measurements of thermal conductivity and density, which are nonstationary due to snow metamorphism. Furthermore, thermal conductivity measurements are typically obtained with specialized heating probes or plates and snow density measurements require digging snow pits. Therefore, direct measurements are difficult to obtain with high enough temporal resolution such that direct comparisons with atmospheric conditions can be made. This study uses highly resolved (7.5 to 10 cm for depth and 1min for time) temperature measurements from the Plaine Morte glacier in Switzerland as initial and boundary conditions to numerically solve the 1D heat equation and iteratively optimize for thermal diffusivity. The method uses flux boundary conditions to constrain thermal diffusivity such that spuriously high values in thermal diffusivity are eliminated. Additionally, a t-test ensuring statistical significance between solutions of varied thermal diffusivity result in further constraints on thermal diffusivity that eliminate spuriously low values. The results show that time resolved (1 minute) thermal diffusivity can be determined from easily implemented and inexpensive temperature measurements of seasonal snow with good agreement to widely used parameterizations based on snow density. This high time resolution further affords the ability to explore possible turbulence-induced enhancements to heat and mass transfer in the snow.
VCG Interpretation through Artificial Learning (VITAL)
Gustafson, D.E.; Womble, M.E.; Lancaster, M.C.
1981-01-01
A system for automated VCG interpretation using tools of artificial intelligence and statistical signal processing is presently under development. The system differs substantially from current programs in the extraction of features to be used for rhythm and morphology interpretation. These are found based on ideas of statistical data compression and sufficient statistics rather than the commonly-used waveform measurements. A relatively large data base is being collected to train and evaluate the statistical pattern recognition algorithms used for interpretation. Representative results are presented to illustrate the approach and system performance.
Januszyk, Michael; Gurtner, Geoffrey C
2011-01-01
The scope of biomedical research has expanded rapidly during the past several decades, and statistical analysis has become increasingly necessary to understand the meaning of large and diverse quantities of raw data. As such, a familiarity with this lexicon is essential for critical appraisal of medical literature. This article attempts to provide a practical overview of medical statistics, with an emphasis on the selection, application, and interpretation of specific tests. This includes a brief review of statistical theory and its nomenclature, particularly with regard to the classification of variables. A discussion of descriptive methods for data presentation is then provided, followed by an overview of statistical inference and significance analysis, and detailed treatment of specific statistical tests and guidelines for their interpretation. PMID:21200241
Invention Activities Support Statistical Reasoning
ERIC Educational Resources Information Center
Smith, Carmen Petrick; Kenlan, Kris
2016-01-01
Students' experiences with statistics and data analysis in middle school are often limited to little more than making and interpreting graphs. Although students may develop fluency in statistical procedures and vocabulary, they frequently lack the skills necessary to apply statistical reasoning in situations other than clear-cut textbook examples.…
ERIC Educational Resources Information Center
Scott, Leslie A.; Ingels, Steven J.
2007-01-01
The search for an understandable reporting format has led the National Assessment Governing Board to explore the possibility of measuring and interpreting student performance on the 12th-grade National Assessment of Educational Progress (NAEP), the Nation's Report Card, in terms of readiness for college, the workplace, and the military. This…
ERIC Educational Resources Information Center
Adams, Wendy K.; Alhadlaq, Hisham; Malley, Christopher V.; Perkins, Katherine K.; Olson, Jonathan; Alshaya, Fahad; Alabdulkareem, Saleh; Wieman, Carl E.
2012-01-01
The PhET Interactive Simulations Project partnered with the Excellence Research Center of Science and Mathematics Education at King Saud University with the joint goal of making simulations useable worldwide. One of the main challenges of this partnership is to make PhET simulations and the website easily translatable into any language. The PhET…
Statistical Reform in School Psychology Research: A Synthesis
ERIC Educational Resources Information Center
Swaminathan, Hariharan; Rogers, H. Jane
2007-01-01
Statistical reform in school psychology research is discussed in terms of research designs, measurement issues, statistical modeling and analysis procedures, interpretation and reporting of statistical results, and finally statistics education.
Summary and interpretive synthesis
1995-05-01
This chapter summarizes the major advances made through our integrated geological studies of the Lisburne Group in northern Alaska. The depositional history of the Lisburne Group is discussed in a framework of depositional sequence stratigraphy. Although individual parasequences (small-scale carbonate cycles) of the Wahoo Limestone cannot be correlated with certainty, parasequence sets can be interpreted as different systems tracts within the large-scale depositional sequences, providing insights on the paleoenvironments, paleogeography and platform geometry. Conodont biostratigraphy precisely established the position of the Mississippian-Pennsylvanian boundary within an important reference section, where established foraminiferal biostratigraphy is inconsistent with respect to conodont-based time-rock boundaries. However, existing Carboniferous conodont zonations are not readily applicable because most zonal indicators are absent, so a local zonation scheme was developed. Diagenetic studies of the Lisburne Group recognized nineteen subaerial exposure surfaces and developed a cement stratigraphy that includes: early cements associated with subaerial exposure surfaces in the Lisburne Group; cements associated with the sub-Permian unconformity; and later burial cements. Subaerial exposure surfaces in the Alapah Limestone are easily explained, being associated with peritidal environments at the boundaries of Sequence A. The Lisburne exposed in ANWR is generally tightly cemented and supermature, but could still be a good reservoir target in the adjacent subsurface of ANWR given the appropriate diagenetic, deformational and thermal history. Our ongoing research on the Lisburne Group will hopefully provide additional insights in future publications.
ERIC Educational Resources Information Center
Markus, Keith A.
2008-01-01
One can distinguish statistical models used in causal modeling from the causal interpretations that align them with substantive hypotheses. Causal modeling typically assumes an efficient causal interpretation of the statistical model. Causal modeling can also make use of mereological causal interpretations in which the state of the parts…
Revisiting the statistical analysis of pyroclast density and porosity data
NASA Astrophysics Data System (ADS)
Bernard, B.; Kueppers, U.; Ortiz, H.
2015-07-01
Explosive volcanic eruptions are commonly characterized based on a thorough analysis of the generated deposits. Amongst other characteristics in physical volcanology, density and porosity of juvenile clasts are some of the most frequently used to constrain eruptive dynamics. In this study, we evaluate the sensitivity of density and porosity data to statistical methods and introduce a weighting parameter to correct issues raised by the use of frequency analysis. Results of textural investigation can be biased by clast selection. Using statistical tools as presented here, the meaningfulness of a conclusion can be checked for any data set easily. This is necessary to define whether or not a sample has met the requirements for statistical relevance, i.e. whether a data set is large enough to allow for reproducible results. Graphical statistics are used to describe density and porosity distributions, similar to those used for grain-size analysis. This approach helps with the interpretation of volcanic deposits. To illustrate this methodology, we chose two large data sets: (1) directed blast deposits of the 3640-3510 BC eruption of Chachimbiro volcano (Ecuador) and (2) block-and-ash-flow deposits of the 1990-1995 eruption of Unzen volcano (Japan). We propose the incorporation of this analysis into future investigations to check the objectivity of results achieved by different working groups and guarantee the meaningfulness of the interpretation.
Cosmic statistics of statistics
NASA Astrophysics Data System (ADS)
Szapudi, István; Colombi, Stéphane; Bernardeau, Francis
1999-12-01
The errors on statistics measured in finite galaxy catalogues are exhaustively investigated. The theory of errors on factorial moments by Szapudi & Colombi is applied to cumulants via a series expansion method. All results are subsequently extended to the weakly non-linear regime. Together with previous investigations this yields an analytic theory of the errors for moments and connected moments of counts in cells from highly non-linear to weakly non-linear scales. For non-linear functions of unbiased estimators, such as the cumulants, the phenomenon of cosmic bias is identified and computed. Since it is subdued by the cosmic errors in the range of applicability of the theory, correction for it is inconsequential. In addition, the method of Colombi, Szapudi & Szalay concerning sampling effects is generalized, adapting the theory for inhomogeneous galaxy catalogues. While previous work focused on the variance only, the present article calculates the cross-correlations between moments and connected moments as well for a statistically complete description. The final analytic formulae representing the full theory are explicit but somewhat complicated. Therefore we have made available a fortran program capable of calculating the described quantities numerically (for further details e-mail SC at colombi@iap.fr). An important special case is the evaluation of the errors on the two-point correlation function, for which this should be more accurate than any method put forward previously. This tool will be immensely useful in the future for assessing the precision of measurements from existing catalogues, as well as aiding the design of new galaxy surveys. To illustrate the applicability of the results and to explore the numerical aspects of the theory qualitatively and quantitatively, the errors and cross-correlations are predicted under a wide range of assumptions for the future Sloan Digital Sky Survey. The principal results concerning the cumulants ξ, Q3 and Q4 is that
An easily regenerable enzyme reactor prepared from polymerized high internal phase emulsions.
Ruan, Guihua; Wu, Zhenwei; Huang, Yipeng; Wei, Meiping; Su, Rihui; Du, Fuyou
2016-04-22
A large-scale high-efficient enzyme reactor based on polymerized high internal phase emulsion monolith (polyHIPE) was prepared. First, a porous cross-linked polyHIPE monolith was prepared by in-situ thermal polymerization of a high internal phase emulsion containing styrene, divinylbenzene and polyglutaraldehyde. The enzyme of TPCK-Trypsin was then immobilized on the monolithic polyHIPE. The performance of the resultant enzyme reactor was assessed according to the conversion ability of Nα-benzoyl-l-arginine ethyl ester to Nα-benzoyl-l-arginine, and the protein digestibility of bovine serum albumin (BSA) and cytochrome (Cyt-C). The results showed that the prepared enzyme reactor exhibited high enzyme immobilization efficiency and fast and easy-control protein digestibility. BSA and Cyt-C could be digested in 10 min with sequence coverage of 59% and 78%, respectively. The peptides and residual protein could be easily rinsed out from reactor and the reactor could be regenerated easily with 4 M HCl without any structure destruction. Properties of multiple interconnected chambers with good permeability, fast digestion facility and easily reproducibility indicated that the polyHIPE enzyme reactor was a good selector potentially applied in proteomics and catalysis areas. PMID:26995089
Chaudhary, Anisha; Kumari, Saroj; Kumar, Rajeev; Teotia, Satish; Singh, Bhanu Pratap; Singh, Avanish Pratap; Dhawan, S K; Dhakate, Sanjay R
2016-04-27
Lightweight and easily foldable with high conductivity, multiwalled carbon nanotube (MWCNT)-based mesocarbon microbead (MCMB) composite paper is prepared using a simple, efficient, and cost-effective strategy. The developed lightweight and conductive composite paper have been reported for the first time as an efficient electromagnetic interference (EMI) shielding material in X-band frequency region having a low density of 0.26 g/cm(3). The investigation revealed that composite paper shows an excellent absorption dominated EMI shielding effectiveness (SE) of -31 to -56 dB at 0.15-0.6 mm thickness, respectively. Specific EMI-SE of as high as -215 dB cm(3)/g exceeds the best values of metal and other low-density carbon-based composites. Additionally, lightweight and easily foldable ability of this composite paper will help in providing stable EMI shielding values even after constant bending. Such intriguing performances open the framework to designing a lightweight and easily foldable composite paper as promising EMI shielding material, especially in next-generation devices and for defense industries. PMID:27035889
A Graphical Interpretation of Probit Coefficients.
ERIC Educational Resources Information Center
Becker, William E.; Waldman, Donald M.
1989-01-01
Contends that, when discrete choice models are taught, particularly the probit model, it is the method rather than the interpretation of the results that is emphasized. This article provides a graphical technique for interpretation of an estimated probit coefficient that will be useful in statistics and econometrics courses. (GG)
Institute of Paper Science Technology
2004-01-30
In recent years, the world has expressed an increasing interest in the recycling of waste paper to supplement the use of virgin fiber as a way to protect the environment. Statistics show that major countries are increasing their use of recycled paper. For example, in 1991 to 1996, the U.S. increased its recovered paper utilization rate from 31% to 39%, Germany went from 50% to 60%, the UK went from 60% to 70%, France increased from 46% to 49%, and China went from 32% to 35% [1]. As recycled fiber levels and water system closures both increase, recycled product quality will need to improve in order for recycled products to compete with products made from virgin fiber [2]. The use of recycled fiber has introduced an increasing level of metal, plastic, and adhesive contamination into the papermaking process which has added to the complexity of the already overwhelming task of providing a uniform and clean recycle furnish. The most harmful of these contaminates is a mixture of adhesives and polymeric substances that are commonly known as stickies. Stickies, which enter the mill with the pulp furnish, are not easily removed from the repulper and become more difficult the further down the system they get. This can be detrimental to the final product quality. Stickies are hydrophobic, tacky, polymeric materials that are introduced into the papermaking system from a mixture of recycled fiber sources. Properties of stickies are very similar to the fibers used in papermaking, viz. size, density, hydrophobicity, and electrokinetic charge. This reduces the probability of their removal by conventional separation processes, such as screening and cleaning, which are based on such properties. Also, their physical and chemical structure allows for them to extrude through screens, attach to fibers, process equipment, wires and felts. Stickies can break down and then reagglomerate and appear at seemingly any place in the mill. When subjected to a number of factors including changes
NASA Astrophysics Data System (ADS)
Grimes, Holly; McMenemy, Karen R.; Ferguson, R. S.
2008-02-01
This paper details how simple PC software, a small network of consumer level PCs, some do-it-yourself hardware and four low cost video projectors can be combined to form an easily configurable and transportable projection display with applications in virtual reality training. This paper provides some observations on the practical difficulties of using such a system, its effectiveness in delivering a VE for training and what benefit may be offered through the deployment of a large number of these low cost environments.
Nicolotti, Orazio; Gillet, Valerie J; Fleming, Peter J; Green, Darren V S
2002-11-01
Deriving quantitative structure-activity relationship (QSAR) models that are accurate, reliable, and easily interpretable is a difficult task. In this study, two new methods have been developed that aim to find useful QSAR models that represent an appropriate balance between model accuracy and complexity. Both methods are based on genetic programming (GP). The first method, referred to as genetic QSAR (or GPQSAR), uses a penalty function to control model complexity. GPQSAR is designed to derive a single linear model that represents an appropriate balance between the variance and the number of descriptors selected for the model. The second method, referred to as multiobjective genetic QSAR (MoQSAR), is based on multiobjective GP and represents a new way of thinking of QSAR. Specifically, QSAR is considered as a multiobjective optimization problem that comprises a number of competitive objectives. Typical objectives include model fitting, the total number of terms, and the occurrence of nonlinear terms. MoQSAR results in a family of equivalent QSAR models where each QSAR represents a different tradeoff in the objectives. A practical consideration often overlooked in QSAR studies is the need for the model to promote an understanding of the biochemical response under investigation. To accomplish this, chemically intuitive descriptors are needed but do not always give rise to statistically robust models. This problem is addressed by the addition of a further objective, called chemical desirability, that aims to reward models that consist of descriptors that are easily interpretable by chemists. GPQSAR and MoQSAR have been tested on various data sets including the Selwood data set and two different solubility data sets. The study demonstrates that the MoQSAR method is able to find models that are at least as good as models derived using standard statistical approaches and also yields models that allow a medicinal chemist to trade statistical robustness for chemical
Safe, Effective and Easily Reproducible Fusion Technique for CV Junction Instability
Sannegowda, Raghavendra Bakki
2015-01-01
Introduction: The Craniovertebral junction (CVJ) refers to a bony enclosure where the occipital bone surrounds the foramen magnum, the atlas and the axis vertebrae. Because of the complexity of structures, CVJ instability is associated with diagnostic and therapeutic problems. Posterior CV fusion procedures have evolved a lot over the last couple of decades. There has been a lookout for one such surgical procedure which is inherently safe, simple, easily reproducible and biomechanically sound. In our study, we present the initial experience the cases of CV junction instrumentation using O-C1-C2 screw & rod construct operated by the author. Aims and Objectives: The current study is a descriptive analysis of the cases of CVJ instability treated by us with instrumentation using O-C1-C2 screw and rod construct fusion technique. Materials and Methods: It is a retrospective, analytical study in which cases of CV junction instability operated by the author between January 2010 to March 2014 were analysed using various clinical, radiological and outcome parameters. Conclusion: CV junction instrumentation using O-C1-C2 screw and rod construct fusion technique proved to be safe, effective, easily reproducible and biomechanically sound technique which can be adopted by all surgeons who may be at any stage of their learning curve. PMID:25954660
Shi, Runhua; McLarty, Jerry W
2009-10-01
In this article, we introduced basic concepts of statistics, type of distributions, and descriptive statistics. A few examples were also provided. The basic concepts presented herein are only a fraction of the concepts related to descriptive statistics. Also, there are many commonly used distributions not presented herein, such as Poisson distributions for rare events and exponential distributions, F distributions, and logistic distributions. More information can be found in many statistics books and publications. PMID:19891281
ERIC Educational Resources Information Center
Petocz, Peter; Sowey, Eric
2008-01-01
As a branch of knowledge, Statistics is ubiquitous and its applications can be found in (almost) every field of human endeavour. In this article, the authors track down the possible source of the link between the "Siren song" and applications of Statistics. Answers to their previous five questions and five new questions on Statistics are presented.
ERIC Educational Resources Information Center
Callamaras, Peter
1983-01-01
This buyer's guide to seven major types of statistics software packages for microcomputers reviews Edu-Ware Statistics 3.0; Financial Planning; Speed Stat; Statistics with DAISY; Human Systems Dynamics package of Stats Plus, ANOVA II, and REGRESS II; Maxistat; and Moore-Barnes' MBC Test Construction and MBC Correlation. (MBR)
ERIC Educational Resources Information Center
Meyer, Donald L.
Bayesian statistical methodology and its possible uses in the behavioral sciences are discussed in relation to the solution of problems in both the use and teaching of fundamental statistical methods, including confidence intervals, significance tests, and sampling. The Bayesian model explains these statistical methods and offers a consistent…
SOCR: Statistics Online Computational Resource
ERIC Educational Resources Information Center
Dinov, Ivo D.
2006-01-01
The need for hands-on computer laboratory experience in undergraduate and graduate statistics education has been firmly established in the past decade. As a result a number of attempts have been undertaken to develop novel approaches for problem-driven statistical thinking, data analysis and result interpretation. In this paper we describe an…
Motivating Play Using Statistical Reasoning
ERIC Educational Resources Information Center
Cross Francis, Dionne I.; Hudson, Rick A.; Lee, Mi Yeon; Rapacki, Lauren; Vesperman, Crystal Marie
2014-01-01
Statistical literacy is essential in everyone's personal lives as consumers, citizens, and professionals. To make informed life and professional decisions, students are required to read, understand, and interpret vast amounts of information, much of which is quantitative. To develop statistical literacy so students are able to make sense of…
Revisiting the statistical analysis of pyroclast density and porosity data
NASA Astrophysics Data System (ADS)
Bernard, B.; Kueppers, U.; Ortiz, H.
2015-03-01
Explosive volcanic eruptions are commonly characterized based on a thorough analysis of the generated deposits. Amongst other characteristics in physical volcanology, density and porosity of juvenile clasts are some of the most frequently used characteristics to constrain eruptive dynamics. In this study, we evaluate the sensitivity of density and porosity data and introduce a weighting parameter to correct issues raised by the use of frequency analysis. Results of textural investigation can be biased by clast selection. Using statistical tools as presented here, the meaningfulness of a conclusion can be checked for any dataset easily. This is necessary to define whether or not a sample has met the requirements for statistical relevance, i.e. whether a dataset is large enough to allow for reproducible results. Graphical statistics are used to describe density and porosity distributions, similar to those used for grain-size analysis. This approach helps with the interpretation of volcanic deposits. To illustrate this methodology we chose two large datasets: (1) directed blast deposits of the 3640-3510 BC eruption of Chachimbiro volcano (Ecuador) and (2) block-and-ash-flow deposits of the 1990-1995 eruption of Unzen volcano (Japan). We propose add the use of this analysis for future investigations to check the objectivity of results achieved by different working groups and guarantee the meaningfulness of the interpretation.
Statistics 101 for Radiologists.
Anvari, Arash; Halpern, Elkan F; Samir, Anthony E
2015-10-01
Diagnostic tests have wide clinical applications, including screening, diagnosis, measuring treatment effect, and determining prognosis. Interpreting diagnostic test results requires an understanding of key statistical concepts used to evaluate test efficacy. This review explains descriptive statistics and discusses probability, including mutually exclusive and independent events and conditional probability. In the inferential statistics section, a statistical perspective on study design is provided, together with an explanation of how to select appropriate statistical tests. Key concepts in recruiting study samples are discussed, including representativeness and random sampling. Variable types are defined, including predictor, outcome, and covariate variables, and the relationship of these variables to one another. In the hypothesis testing section, we explain how to determine if observed differences between groups are likely to be due to chance. We explain type I and II errors, statistical significance, and study power, followed by an explanation of effect sizes and how confidence intervals can be used to generalize observed effect sizes to the larger population. Statistical tests are explained in four categories: t tests and analysis of variance, proportion analysis tests, nonparametric tests, and regression techniques. We discuss sensitivity, specificity, accuracy, receiver operating characteristic analysis, and likelihood ratios. Measures of reliability and agreement, including κ statistics, intraclass correlation coefficients, and Bland-Altman graphs and analysis, are introduced. PMID:26466186
Solving block linear systems with low-rank off-diagonal blocks is easily parallelizable
Menkov, V.
1996-12-31
An easily and efficiently parallelizable direct method is given for solving a block linear system Bx = y, where B = D + Q is the sum of a non-singular block diagonal matrix D and a matrix Q with low-rank blocks. This implicitly defines a new preconditioning method with an operation count close to the cost of calculating a matrix-vector product Qw for some w, plus at most twice the cost of calculating Qw for some w. When implemented on a parallel machine the processor utilization can be as good as that of those operations. Order estimates are given for the general case, and an implementation is compared to block SSOR preconditioning.
An easily Prepared Fluorescent pH Probe Based on Dansyl.
Sha, Chunming; Chen, Yuhua; Chen, Yufen; Xu, Dongmei
2016-09-01
A novel fluorescent pH probe from dansyl chloride and thiosemicarbazide was easily prepared and fully characterized by (1)H NMR, (13)C NMR, LC-MS, Infrared spectra and elemental analysis. The probe exhibited high selectivity and sensitivity to H(+) with a pK a value of 4.98. The fluorescence intensity at 510 nm quenched 99.5 % when the pH dropped from 10.88 to 1.98. In addition, the dansyl-based probe could respond quickly and reversibly to the pH variation and various common metal ions showed negligible interference. The recognition could be ascribed to the intramolecular charge transfer caused by the protonation of the nitrogen in the dimethylamino group. PMID:27333798
A 2D zinc-organic network being easily exfoliated into isolated sheets
NASA Astrophysics Data System (ADS)
Yu, Guihong; Li, Ruiqing; Leng, Zhihua; Gan, Shucai
2016-08-01
A metal-organic aggregate, namely {Zn2Cl2(BBC)}n (BBC = 4,4‧,4‧‧-(benzene-1,3,5-triyl-tris(benzene-4,1-diyl))tribenzoate) was obtained by solvothermal synthesis. Its structure is featured with the Zn2(COO)3 paddle-wheels with two chloride anions on axial positions and hexagonal pores in the layers. The exclusion of water in the precursor and the solvent plays a crucial role in the formation of target compound. This compound can be easily dissolved in alkaline solution and exfoliated into isolated sheets, which shows a novel way for the preparation of 2D materials.
NASA Astrophysics Data System (ADS)
Julián-López, Beatriz; Gonell, Francisco; Lima, Patricia P.; Freitas, Vânia T.; André, Paulo S.; Carlos, Luis D.; Ferreira, Rute A. S.
2015-10-01
This manuscript reports the synthesis and characterization of the first organic-inorganic hybrid material exhibiting efficient multimodal spectral converting properties. The nanocomposite, made of Er3+, Yb3+ codoped zirconia nanoparticles (NPs) entrapped in a di-ureasil d-U(600) hybrid matrix, is prepared by an easy two-step sol-gel synthesis leading to homogeneous and transparent materials that can be very easily processed as monolith or film. Extensive structural characterization reveals that zirconia nanocrystals of 10-20 nm in size are efficiently dispersed into the hybrid matrix and that the local structure of the di-ureasil is not affected by the presence of the NPs. A significant enhancement in the refractive index of the di-ureasil matrix with the incorporation of the ZrO2 nanocrystals is observed. The optical study demonstrates that luminescent properties of both constituents are perfectly preserved in the final hybrid. Thus, the material displays a white-light photoluminescence from the di-ureasil component upon excitation at UV/visible radiation and also intense green and red emissions from the Er3+- and Yb3+-doped NPs after NIR excitation. The dynamics of the optical processes were also studied as a function of the lanthanide content and the thickness of the films. Our results indicate that these luminescent hybrids represent a low-cost, environmentally friendly, size-controlled, easily processed and chemically stable alternative material to be used in light harvesting devices such as luminescent solar concentrators, optical fibres and sensors. Furthermore, this synthetic approach can be extended to a wide variety of luminescent NPs entrapped in hybrid matrices, thus leading to multifunctional and versatile materials for efficient tuneable nonlinear optical nanodevices.
Julián-López, Beatriz; Gonell, Francisco; Lima, Patricia P; Freitas, Vânia T; André, Paulo S; Carlos, Luis D; Ferreira, Rute A S
2015-10-01
This manuscript reports the synthesis and characterization of the first organic-inorganic hybrid material exhibiting efficient multimodal spectral converting properties. The nanocomposite, made of Er(3+), Yb(3+) codoped zirconia nanoparticles (NPs) entrapped in a di-ureasil d-U(600) hybrid matrix, is prepared by an easy two-step sol-gel synthesis leading to homogeneous and transparent materials that can be very easily processed as monolith or film. Extensive structural characterization reveals that zirconia nanocrystals of 10-20 nm in size are efficiently dispersed into the hybrid matrix and that the local structure of the di-ureasil is not affected by the presence of the NPs. A significant enhancement in the refractive index of the di-ureasil matrix with the incorporation of the ZrO2 nanocrystals is observed. The optical study demonstrates that luminescent properties of both constituents are perfectly preserved in the final hybrid. Thus, the material displays a white-light photoluminescence from the di-ureasil component upon excitation at UV/visible radiation and also intense green and red emissions from the Er(3+)- and Yb(3+)-doped NPs after NIR excitation. The dynamics of the optical processes were also studied as a function of the lanthanide content and the thickness of the films. Our results indicate that these luminescent hybrids represent a low-cost, environmentally friendly, size-controlled, easily processed and chemically stable alternative material to be used in light harvesting devices such as luminescent solar concentrators, optical fibres and sensors. Furthermore, this synthetic approach can be extended to a wide variety of luminescent NPs entrapped in hybrid matrices, thus leading to multifunctional and versatile materials for efficient tuneable nonlinear optical nanodevices. PMID:26374133
The study on development of easily chewable and swallowable foods for elderly
Kim, Soojeong
2015-01-01
BACKGROUND/OBJECTS When the functions involved in the ingestion of food occurs failure, not only loss of enjoyment of eating, it will be faced with protein-energy malnutrition. Dysmasesis and difficulty of swallowing occurs in various diseases, but it may be a major cause of aging, and elderly people with authoring and dysmasesis and difficulty of swallowing in the aging society is expected to increase rapidly. SUBJECTS/METHODS In this study, we carried out a survey targeting nutritionists who work in elderly care facilities, and examined characteristics of offering of foods for elderly and the degree of demand of development of easily chewable and swallowable foods for the elderly who can crush foods and take that by their own tongues, and sometimes have difficulty in drinking water and tea. RESULTS In elderly care facilities, it was found to provide a finely chopped food or ground food that was ground with water in a blender for elderly with dysmasesis. Elderly satisfaction of provided foods is appeared overall low. Results of investigating the applicability of foods for elderly and the reflection will of menus, were showed the highest response rate in a gelification method in molecular gastronomic science technics, and results of investigating the frequent food of the elderly; representative menu of beef, pork, white fish, anchovies and spinach, were showed Korean barbecue beef, hot pepper paste stir fried pork, pan fried white fish, stir fried anchovy, seasoned spinach were the highest offer frequency. CONCLUSIONS This study will provide the fundamentals of the development of easily chewable and swallowable foods, gelification, for the elderly. The study will also illustrate that, in the elderly, food undergone gelification will reduce the risk of swallowing down to the wrong pipe and improve overall food preference. PMID:26244082
Effects of easily ionizable elements on the liquid sampling atmospheric pressure glow discharge
NASA Astrophysics Data System (ADS)
Venzie, Jacob L.; Marcus, R. Kenneth
2006-06-01
A series of studies has been undertaken to determine the susceptibility of the liquid sampling-atmospheric pressure glow discharge (LS-APGD) atomic emission source to easily ionizable element (EIE) effects. The initial portions of the study involved monitoring the voltage drop across the plasma as a function of the pH to ascertain whether or not the conductivity of the liquid eluent alters the plasma energetics and subsequently the analyte signal strength. It was found that altering the pH (0.0 to 2.0) in the sample matrix did not significantly change the discharge voltage. The emission signal intensities for Cu(I) 327.4 nm, Mo(I) 344.7 nm, Sc(I) 326.9 nm and Hg(I) 253.6 nm were measured as a function of the easily ionizable element (sodium and calcium) concentration in the injection matrix. A range of 0.0 to 0.1% (w/v) EIE in the sample matrix did not cause a significant change in the Cu, Sc, and Mo signal-to-background ratios, with only a slight change noted for Hg. In addition to this test of analyte response, the plasma energetics as a function of EIE concentration are assessed using the ratio of Mg(II) to Mg(I) (280.2 nm and 285.2 nm, respectively) intensities. The Mg(II)/Mg(I) ratio showed that the plasma energetics did not change significantly over the same range of EIE addition. These results are best explained by the electrolytic nature of the eluent acting as an ionic (and perhaps spectrochemical) buffer.
Estimation of nutrient values of pig slurries in Southeast Spain using easily determined properties.
Moral, R; Perez-Murcia, M D; Perez-Espinosa, A; Moreno-Caselles, J; Paredes, C
2005-01-01
The contents of available nutrients in pig slurries are not easy to quantify in situ without laboratory facilities, but chemical analyses using standard laboratory methods also take time and are costly and not practical for most farms. Thus, when animal slurries are applied to land, their fertiliser potential is often unknown. In addition, in the last years, the changes in the management of industrial piggeries has changed the nature of the pig slurries vg. decrease of the dry matter content, and consequently the methods and equations used for estimating the nutrient contents in these residues must be checked. In our study, slurry samples were collected from the storage tanks of 36 commercial farms in Southeast Spain. Samples were analysed for pH, electrical conductivity (EC), redox potential (RP), specific density (D), total solids (TS), sedimentable solids (SS), biological oxygen demand (BOD(5)), chemical oxygen demand (COD), total nitrogen (TKN), ammonium nitrogen (AN), organic nitrogen (ON), and total contents of phosphorus, potassium, calcium and magnesium. Relationships between major nutrient levels of pig slurries and a range of physical and chemical properties were investigated. We also analysed the variability of pig slurries according to the production stage. TKN, AN and K were closely related to EC. The P content in slurries was related more closely to solids-derived parameters such as D. The use of multiple properties to estimate nutrient contents in pig slurries, especially for AN and K, seemed unnecessary due to the limited improvement achieved with an additional property. Therefore, electrical conductivity seemed to be the most appropriate single, easily determined parameter for estimation of total and ammonium nitrogen and potassium in pig slurries, with more than 83% of the variance explained. P seemed to be the worst key nutrient for estimation using any easily determined parameter. PMID:16009306
Kogalovskii, M.R.
1995-03-01
This paper presents a review of problems related to statistical database systems, which are wide-spread in various fields of activity. Statistical databases (SDB) are referred to as databases that consist of data and are used for statistical analysis. Topics under consideration are: SDB peculiarities, properties of data models adequate for SDB requirements, metadata functions, null-value problems, SDB compromise protection problems, stored data compression techniques, and statistical data representation means. Also examined is whether the present Database Management Systems (DBMS) satisfy the SDB requirements. Some actual research directions in SDB systems are considered.
Smith, Alwyn
1969-01-01
This paper is based on an analysis of questionnaires sent to the health ministries of Member States of WHO asking for information about the extent, nature, and scope of morbidity statistical information. It is clear that most countries collect some statistics of morbidity and many countries collect extensive data. However, few countries relate their collection to the needs of health administrators for information, and many countries collect statistics principally for publication in annual volumes which may appear anything up to 3 years after the year to which they refer. The desiderata of morbidity statistics may be summarized as reliability, representativeness, and relevance to current health problems. PMID:5306722
Comprehensive Interpretive Planning.
ERIC Educational Resources Information Center
Kohen, Richard; Sikoryak, Kim
1999-01-01
Discusses interpretive planning and provides information on how to maximize a sense of ownership shared by managers, staff, and other organizational shareholders. Presents practical and effective plans for providing interpretive services. (CCM)
Easily Regenerable Solid Adsorbents Based on Polyamines for Carbon Dioxide Capture from the Air
Goeppert, A; Zhang, H; Czaun, M; May, RB; Prakash, GKS; Olah, GA; Narayanan, SR
2014-03-18
Adsorbents prepared easily by impregnation of fumed silica with polyethylenimine (PEI) are promising candidates for the capture of CO2 directly from the air. These inexpensive adsorbents have high CO2 adsorption capacity at ambient temperature and can be regenerated in repeated cycles under mild conditions. Despite the very low CO2 concentration, they are able to scrub efficiently all CO2 out of the air in the initial hours of the experiments. The influence of parameters such as PEI loading, adsorption and desorption temperature, particle size, and PEI molecular weight on the adsorption behavior were investigated. The mild regeneration temperatures required could allow the use of waste heat available in many industrial processes as well as solar heat. CO2 adsorption from the air has a number of applications. Removal of CO2 from a closed environment, such as a submarine or space vehicles, is essential for life support. The supply of CO2-free air is also critical for alkaline fuel cells and batteries. Direct air capture of CO2 could also help mitigate the rising concerns about atmospheric CO2 concentration and associated climatic changes, while, at the same time, provide the first step for an anthropogenic carbon cycle.
Shaft seals with an easily removable cylinder holder for low-pressure steam turbines
NASA Astrophysics Data System (ADS)
Zakharov, A. E.; Rodionov, D. A.; Pimenov, E. V.; Sobolev, A. S.
2016-01-01
The article is devoted to the problems that occur at the operation of LPC shaft seals (SS) of turbines, particularly, their bearings. The problems arising from the deterioration of oil-protecting rings of SS and bearings and also the consequences in which they can result are considered. The existing SS housing construction types are considered. Their operational features are specified. A new SS construction type with an easily removable holder is presented. The construction of its main elements is described. The sequence of operations of the repair personnel at the restoration of the new SS type spacings is proposed. The comparative analysis of the new and the existing SS construction types is carried out. The assessment results of the efficiency, the operational convenience, and the economic effect after the installation of the new type seals are given. The conclusions about the offered construction prospects are made by results of the comparative analysis and the carried-out assessment. The main advantage of this design is the possibility of spacings restoration both in SS and in oil-protecting rings during a short-term stop of a turbine, even without its cooling. This construction was successfully tested on the working K-300-23.5 LMP turbine. However, its adaptation for other turbines is quite possible.
Zhang, Huai-Zhi; Zhang, Chang; Zeng, Guang-Ming; Gong, Ji-Lai; Ou, Xiao-Ming; Huan, Shuang-Yan
2016-06-01
Silver nanoparticle-decorated magnetic graphene oxide (MGO-Ag) was synthesized by doping silver and Fe3O4 nanoparticles on the surface of GO, which was used as an antibacterial agent. MGO-Ag was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy dispersive X-ray (EDS), X-ray diffraction (XRD), Raman spectroscopy and magnetic property tests. It can be found that magnetic iron oxide nanoparticles and nano-Ag was well dispersed on graphene oxide; and MGO-Ag exhibited excellent antibacterial activity against Escherichia coli and Staphylococcus aureus. Several factors were investigated to study the antibacterial effect of MGO-Ag, such as temperature, time, pH and bacterial concentration. We also found that MGO-Ag maintained high inactivation rates after use six times and can be separated easily after antibacterial process. Moreover, the antibacterial mechanism is discussed and the synergistic effect of GO, Fe3O4 nanoparticles and nano-Ag accounted for high inactivation of MGO-Ag. PMID:26994349
Binford, Greta J; Gillespie, Rosemary G; Maddison, Wayne P
2016-05-01
Spider venom composition typically differs between sexes. This pattern is anecdotally thought to reflect differences in adult feeding biology. We used a phylogenetic approach to compare intersexual venom dimorphism between species that differ in adult niche dimorphism. Male and female venoms were compared within and between related species of Hawaiian Tetragnatha, a mainland congener, and outgroups. In some species of Hawaiian Tetragnatha adult females spin orb-webs and adult males capture prey while wandering, while in other species both males and females capture prey by wandering. We predicted that, if venom sexual dimorphism is primarily explained by differences in adult feeding biology, species in which both sexes forage by wandering would have monomorphic venoms or venoms with reduced dimorphism relative to species with different adult feeding biology. However, we found striking sexual dimorphism in venoms of both wandering and orb-weaving Tetragnatha species with males having high molecular weight components in their venoms that were absent in females, and a reduced concentration of low molecular weight components relative to females. Intersexual differences in venom composition within Tetragnatha were significantly larger than in non-Tetragnatha species. Diet composition was not different between sexes. This striking venom dimorphism is not easily explained by differences in feeding ecology or behavior. Rather, we hypothesize that the dimorphism reflects male-specific components that play a role in mating biology possibly in sexual stimulation, nuptial gifts and/or mate recognition. PMID:26908290
Easily regenerable solid adsorbents based on polyamines for carbon dioxide capture from the air.
Goeppert, Alain; Zhang, Hang; Czaun, Miklos; May, Robert B; Prakash, G K Surya; Olah, George A; Narayanan, S R
2014-05-01
Adsorbents prepared easily by impregnation of fumed silica with polyethylenimine (PEI) are promising candidates for the capture of CO2 directly from the air. These inexpensive adsorbents have high CO2 adsorption capacity at ambient temperature and can be regenerated in repeated cycles under mild conditions. Despite the very low CO2 concentration, they are able to scrub efficiently all CO2 out of the air in the initial hours of the experiments. The influence of parameters such as PEI loading, adsorption and desorption temperature, particle size, and PEI molecular weight on the adsorption behavior were investigated. The mild regeneration temperatures required could allow the use of waste heat available in many industrial processes as well as solar heat. CO2 adsorption from the air has a number of applications. Removal of CO2 from a closed environment, such as a submarine or space vehicles, is essential for life support. The supply of CO2-free air is also critical for alkaline fuel cells and batteries. Direct air capture of CO2 could also help mitigate the rising concerns about atmospheric CO2 concentration and associated climatic changes, while, at the same time, provide the first step for an anthropogenic carbon cycle. PMID:24644023
Open Window: When Easily Identifiable Genomes and Traits Are in the Public Domain
Angrist, Misha
2014-01-01
“One can't be of an enquiring and experimental nature, and still be very sensible.” - Charles Fort [1] As the costs of personal genetic testing “self-quantification” fall, publicly accessible databases housing people's genotypic and phenotypic information are gradually increasing in number and scope. The latest entrant is openSNP, which allows participants to upload their personal genetic/genomic and self-reported phenotypic data. I believe the emergence of such open repositories of human biological data is a natural reflection of inquisitive and digitally literate people's desires to make genomic and phenotypic information more easily available to a community beyond the research establishment. Such unfettered databases hold the promise of contributing mightily to science, science education and medicine. That said, in an age of increasingly widespread governmental and corporate surveillance, we would do well to be mindful that genomic DNA is uniquely identifying. Participants in open biological databases are engaged in a real-time experiment whose outcome is unknown. PMID:24647311
ERIC Educational Resources Information Center
Petocz, Peter; Sowey, Eric
2008-01-01
In this article, the authors focus on hypothesis testing--that peculiarly statistical way of deciding things. Statistical methods for testing hypotheses were developed in the 1920s and 1930s by some of the most famous statisticians, in particular Ronald Fisher, Jerzy Neyman and Egon Pearson, who laid the foundations of almost all modern methods of…
Hart, Dionne; Bowen, Juan; DeJesus, Ramona; Maldonado, Alejandro; Jiwa, Fatima
2010-04-01
Research has demonstrated that appropriate use of interpreters in clinical encounters improves outcomes and decreases adverse events. This article reviews both the medical reasons for working with trained medical interpreters and the related laws, and offers practical tips for working effectively with interpreters. PMID:20481167
ERIC Educational Resources Information Center
Darroch, Kathleen
2010-01-01
An interpreter's role is to facilitate communication and convey all auditory and signed information so that both hearing and deaf individuals may fully interact. The common types of services provided by interpreters are: (1) American Sign Language (ASL) Interpretation--a visual-gestural language with its own linguistic features; (2) Sign Language…
Journalists as Interpretive Communities.
ERIC Educational Resources Information Center
Zelizer, Barbie
1993-01-01
Proposes viewing journalists as members of an interpretive community (not a profession) united by its shared discourse and collective interpretations of key public events. Applies the frame of the interpretive community to journalistic discourse about two events central for American journalists--Watergate and McCarthyism. (SR)
Interpreting. NETAC Teacher Tipsheet.
ERIC Educational Resources Information Center
Darroch, Kathy; Marshall, Liza
This tipsheet explains that an interpreter's role is to facilitate communication and convey all auditory and signed information so that individuals with and without hearing may fully interact. It outlines the common types of services provided by interpreters, and discusses principles guiding the professional behaviors of interpreters. When working…
A Note on a Geometric Interpretation of the Correlation Coefficient.
ERIC Educational Resources Information Center
Marks, Edmond
1982-01-01
An alternate geometric interpretation of the correlation coefficient to that given in most statistics texts for psychology and education is presented. This interpretation is considered to be more consistent with the statistical model for the data, and richer in geometric meaning. (Author)
Enhancing Table Interpretation Skills via Training in Table Creation
ERIC Educational Resources Information Center
Karazsia, Bryan T.
2013-01-01
Quantitative and statistical literacy are core domains in the undergraduate psychology curriculum. An important component of such literacy includes interpretation of visual aids, such as tables containing results from statistical analyses. This article presents a new technique for enhancing student interpretation of American Psychological…
The emergent Copenhagen interpretation of quantum mechanics
NASA Astrophysics Data System (ADS)
Hollowood, Timothy J.
2014-05-01
We introduce a new and conceptually simple interpretation of quantum mechanics based on reduced density matrices of sub-systems from which the standard Copenhagen interpretation emerges as an effective description of macroscopically large systems. This interpretation describes a world in which definite measurement results are obtained with probabilities that reproduce the Born rule. Wave function collapse is seen to be a useful but fundamentally unnecessary piece of prudent book keeping which is only valid for macro-systems. The new interpretation lies in a class of modal interpretations in that it applies to quantum systems that interact with a much larger environment. However, we show that it does not suffer from the problems that have plagued similar modal interpretations like macroscopic superpositions and rapid flipping between macroscopically distinct states. We describe how the interpretation fits neatly together with fully quantum formulations of statistical mechanics and that a measurement process can be viewed as a process of ergodicity breaking analogous to a phase transition. The key feature of the new interpretation is that joint probabilities for the ergodic subsets of states of disjoint macro-systems only arise as emergent quantities. Finally we give an account of the EPR-Bohm thought experiment and show that the interpretation implies the violation of the Bell inequality characteristic of quantum mechanics but in a way that is rather novel. The final conclusion is that the Copenhagen interpretation gives a completely satisfactory phenomenology of macro-systems interacting with micro-systems.
Dynamical interpretation of conditional patterns
NASA Technical Reports Server (NTRS)
Adrian, R. J.; Moser, R. D.; Moin, P.
1988-01-01
While great progress is being made in characterizing the 3-D structure of organized turbulent motions using conditional averaging analysis, there is a lack of theoretical guidance regarding the interpretation and utilization of such information. Questions concerning the significance of the structures, their contributions to various transport properties, and their dynamics cannot be answered without recourse to appropriate dynamical governing equations. One approach which addresses some of these questions uses the conditional fields as initial conditions and calculates their evolution from the Navier-Stokes equations, yielding valuable information about stability, growth, and longevity of the mean structure. To interpret statistical aspects of the structures, a different type of theory which deals with the structures in the context of their contributions to the statistics of the flow is needed. As a first step toward this end, an effort was made to integrate the structural information from the study of organized structures with a suitable statistical theory. This is done by stochastically estimating the two-point conditional averages that appear in the equation for the one-point probability density function, and relating the structures to the conditional stresses. Salient features of the estimates are identified, and the structure of the one-point estimates in channel flow is defined.
Interpreting Abstract Interpretations in Membership Equational Logic
NASA Technical Reports Server (NTRS)
Fischer, Bernd; Rosu, Grigore
2001-01-01
We present a logical framework in which abstract interpretations can be naturally specified and then verified. Our approach is based on membership equational logic which extends equational logics by membership axioms, asserting that a term has a certain sort. We represent an abstract interpretation as a membership equational logic specification, usually as an overloaded order-sorted signature with membership axioms. It turns out that, for any term, its least sort over this specification corresponds to its most concrete abstract value. Maude implements membership equational logic and provides mechanisms to calculate the least sort of a term efficiently. We first show how Maude can be used to get prototyping of abstract interpretations "for free." Building on the meta-logic facilities of Maude, we further develop a tool that automatically checks and abstract interpretation against a set of user-defined properties. This can be used to select an appropriate abstract interpretation, to characterize the specified loss of information during abstraction, and to compare different abstractions with each other.
Denion, Eric; Lux, Anne-Laure; Mouriaux, Frédéric; Béraud, Guillaume
2016-01-01
Introduction We aimed to determine the limbal lighting illuminance thresholds (LLITs) required to trigger perception of sclerotic scatter at the opposite non-illuminated limbus (i.e. perception of a light limbal scleral arc) under different levels of ambient lighting illuminance (ALI). Material and Methods Twenty healthy volunteers were enrolled. The iris shade (light or dark) was graded by retrieving the median value of the pixels of a pre-determined zone of a gray-level iris photograph. Mean keratometry and central corneal pachymetry were recorded. Each subject was asked to lie down, and the ALI at eye level was set to mesopic values (10, 20, 40 lux), then photopic values (60, 80, 100, 150, 200 lux). For each ALI level, a light beam of gradually increasing illuminance was applied to the right temporal limbus until the LLIT was reached, i.e. the level required to produce the faint light arc that is characteristic of sclerotic scatter at the nasal limbus. Results After log-log transformation, a linear relationship between the logarithm of ALI and the logarithm of the LLIT was found (p<0.001), a 10% increase in ALI being associated with an average increase in the LLIT of 28.9%. Higher keratometry values were associated with higher LLIT values (p = 0.008) under low ALI levels, but the coefficient of the interaction was very small, representing a very limited effect. Iris shade and central corneal thickness values were not significantly associated with the LLIT. We also developed a censored linear model for ALI values ≤ 40 lux, showing a linear relationship between ALI and the LLIT, in which the LLIT value was 34.4 times greater than the ALI value. Conclusion Sclerotic scatter is more easily elicited under mesopic conditions than under photopic conditions and requires the LLIT value to be much higher than the ALI value, i.e. it requires extreme contrast. PMID:26964096
Hijnen, W A M; Biraud, D; Cornelissen, E R; van der Kooij, D
2009-07-01
One of the major impediments in the application of spiral-wound membranes in water treatment or desalination is clogging of the feed channel by biofouling which is induced by nutrients in the feedwater. Organic carbon is, under most conditions, limiting the microbial growth. The objective of this study is to assess the relationship between the concentration of an easily assimilable organic compound such as acetate in the feedwater and the pressure drop increase in the feed channel. For this purpose the membrane fouling simulator (MFS) was used as a model for the feed channel of a spiral-wound membrane. This MFS unit was supplied with drinking water enriched with acetate at concentrations ranging from 1 to 1000 microg C x L(-1). The pressure drop (PD) in the feed channel increased at all tested concentrations but not with the blank. The PD increase could be described by a first order process based on theoretical considerations concerning biofilm formation rate and porosity decline. The relationship between the first order fouling rate constant R(f) and the acetate concentration is described with a saturation function corresponding with the growth kinetics of bacteria. Under the applied conditions the maximum R(f) (0.555 d(-1)) was reached at 25 microg acetate-C x L(-1) and the half saturation constant k(f) was estimated at 15 microg acetate-C x L(-1). This value is higher than k(s) values for suspended bacteria grown on acetate, which is attributed to substrate limited growth conditions in the biofilm. The threshold concentration for biofouling of the feed channel is about 1 microg acetate-C x L(-1). PMID:19673281
Clearly written, easily comprehended? The readability of websites providing information on epilepsy.
Brigo, Francesco; Otte, Willem M; Igwe, Stanley C; Tezzon, Frediano; Nardone, Raffaele
2015-03-01
There is a general need for high-quality, easily accessible, and comprehensive health-care information on epilepsy to better inform the general population about this highly stigmatized neurological disorder. The aim of this study was to evaluate the health literacy level of eight popular English-written websites that provide information on epilepsy in quantitative terms of readability. Educational epilepsy material on these websites, including 41 Wikipedia articles, were analyzed for their overall level of readability and the corresponding academic grade level needed to comprehend the published texts on the first reading. The Flesch Reading Ease (FRE) was used to assess ease of comprehension while the Gunning Fog Index, Coleman-Liau Index, Flesch-Kincaid Grade Level, Automated Readability Index, and Simple Measure of Gobbledygook scales estimated the corresponding academic grade level needed for comprehension. The average readability of websites yielded results indicative of a difficult-to-fairly-difficult readability level (FRE results: 44.0±8.2), with text readability corresponding to an 11th academic grade level (11.3±1.9). The average FRE score of the Wikipedia articles was indicative of a difficult readability level (25.6±9.5), with the other readability scales yielding results corresponding to a 14th grade level (14.3±1.7). Popular websites providing information on epilepsy, including Wikipedia, often demonstrate a low level of readability. This can be ameliorated by increasing access to clear and concise online information on epilepsy and health in general. Short "basic" summaries targeted to patients and nonmedical users should be added to articles published in specialist websites and Wikipedia to ease readability. PMID:25601720
Kokal, Idil; Engel, Annerose; Kirschner, Sebastian; Keysers, Christian
2011-01-01
Why does chanting, drumming or dancing together make people feel united? Here we investigate the neural mechanisms underlying interpersonal synchrony and its subsequent effects on prosocial behavior among synchronized individuals. We hypothesized that areas of the brain associated with the processing of reward would be active when individuals experience synchrony during drumming, and that these reward signals would increase prosocial behavior toward this synchronous drum partner. 18 female non-musicians were scanned with functional magnetic resonance imaging while they drummed a rhythm, in alternating blocks, with two different experimenters: one drumming in-synchrony and the other out-of-synchrony relative to the participant. In the last scanning part, which served as the experimental manipulation for the following prosocial behavioral test, one of the experimenters drummed with one half of the participants in-synchrony and with the other out-of-synchrony. After scanning, this experimenter “accidentally” dropped eight pencils, and the number of pencils collected by the participants was used as a measure of prosocial commitment. Results revealed that participants who mastered the novel rhythm easily before scanning showed increased activity in the caudate during synchronous drumming. The same area also responded to monetary reward in a localizer task with the same participants. The activity in the caudate during experiencing synchronous drumming also predicted the number of pencils the participants later collected to help the synchronous experimenter of the manipulation run. In addition, participants collected more pencils to help the experimenter when she had drummed in-synchrony than out-of-synchrony during the manipulation run. By showing an overlap in activated areas during synchronized drumming and monetary reward, our findings suggest that interpersonal synchrony is related to the brain's reward system. PMID:22110623
Rangel, Thomaz C; Michels, Alexandre F; Horowitz, Flávio; Weibel, Daniel E
2015-03-24
Textures that resemble typical fern or bracken plant species (dendrite structures) were fabricated for liquid repellency by dipping copper substrates in a single-step process in solutions containing AgNO3 or by a simple spray liquid application. Superhydrophobic surfaces were produced using a solution containing AgNO3 and trimethoxypropylsilane (TMPSi), and superomniphobic surfaces were produced by a two-step procedure, immersing the copper substrate in a AgNO3 solution and, after that, in a solution containing 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES). The simple functionalization processes can also be used when the superomniphobic surfaces were destroyed by mechanical stress. By immersion of the wrecked surfaces in the above solutions or by the spray method and soft heating, the copper substrates could be easily repaired, regenerating the surfaces' superrepellency to liquids. The micro- and nanoroughness structures generated on copper surfaces by the deposition of silver dendrites functionalized with TMPSi presented apparent contact angles greater than 150° with a contact angle hysteresis lower than 10° when water was used as the test liquid. To avoid total wettability with very low surface tension liquids, such as rapeseed oil and hexadecane, a thin perfluorinated coating of poly(tetrafluoroethylene) (PTFE), produced by physical vapor deposition, was used. A more efficient perfluorinated coating was obtained when PFDTES was used. The superomniphobic surfaces produced apparent contact angles above 150° with all of the tested liquids, including hexadecane, although the contact angle hysteresis with this liquid was above 10°. The coupling of dendritic structures with TMPSi/PTFE or directly by PFDTES coatings was responsible for the superrepellency of the as-prepared surfaces. These simple, fast, and reliable procedures allow the large area, and cost-effective scale fabrication of superrepellent surfaces on copper substrates for various industrial
Farcau, Cosmin; Potara, Monica; Leordean, Cosmin; Boca, Sanda; Astilean, Simion
2013-01-21
The ability to easily prepare Surface Enhanced Raman Scattering (SERS) substrates by the assembly of chemically synthesized gold nanocolloids is of great interest for the advancement of SERS-based optical detection and identification of molecular species of biological or chemical interest, pollutants or warfare agents. In this work we employ three very simple strategies, which can be implemented in any laboratory without the need for specialized equipment, to prepare assemblies of citrate-stabilized spherical gold colloids: (i) drop-coating, which induces the assembly of colloids in so-called coffee rings; (ii) a simplified variant of convective self-assembly (CSA), based on water evaporation in a constrained geometry, which yields highly uniform strips of nanoparticles (NP); (iii) assembly onto chemically functionalized glass surfaces which yields randomly assembled colloids and colloidal clusters. The SERS properties of the resulting colloidal assemblies are comparatively evaluated under multiple excitation lines with p-aminothiophenol (pATP) as a model Raman scatterer. The NP strips obtained by CSA prove to be SERS-active both in the visible and NIR and possess a highly uniform SERS response as demonstrated by spectra at individually selected sites and by confocal SERS mapping. Further it is shown that these NP strips are effective for the detection of cytosine, a DNA component, and for multi-analyte SERS detection. These results, showing how an efficient SERS substrate can be obtained by a very simple assembly method from easy-to-synthesize colloidal gold NP, can have an impact on the development of analytical SERS applications. PMID:23171872
Perception in statistical graphics
NASA Astrophysics Data System (ADS)
VanderPlas, Susan Ruth
There has been quite a bit of research on statistical graphics and visualization, generally focused on new types of graphics, new software to create graphics, interactivity, and usability studies. Our ability to interpret and use statistical graphics hinges on the interface between the graph itself and the brain that perceives and interprets it, and there is substantially less research on the interplay between graph, eye, brain, and mind than is sufficient to understand the nature of these relationships. The goal of the work presented here is to further explore the interplay between a static graph, the translation of that graph from paper to mental representation (the journey from eye to brain), and the mental processes that operate on that graph once it is transferred into memory (mind). Understanding the perception of statistical graphics should allow researchers to create more effective graphs which produce fewer distortions and viewer errors while reducing the cognitive load necessary to understand the information presented in the graph. Taken together, these experiments should lay a foundation for exploring the perception of statistical graphics. There has been considerable research into the accuracy of numerical judgments viewers make from graphs, and these studies are useful, but it is more effective to understand how errors in these judgments occur so that the root cause of the error can be addressed directly. Understanding how visual reasoning relates to the ability to make judgments from graphs allows us to tailor graphics to particular target audiences. In addition, understanding the hierarchy of salient features in statistical graphics allows us to clearly communicate the important message from data or statistical models by constructing graphics which are designed specifically for the perceptual system.
Basic statistics in cell biology.
Vaux, David L
2014-01-01
The physicist Ernest Rutherford said, "If your experiment needs statistics, you ought to have done a better experiment." Although this aphorism remains true for much of today's research in cell biology, a basic understanding of statistics can be useful to cell biologists to help in monitoring the conduct of their experiments, in interpreting the results, in presenting them in publications, and when critically evaluating research by others. However, training in statistics is often focused on the sophisticated needs of clinical researchers, psychologists, and epidemiologists, whose conclusions depend wholly on statistics, rather than the practical needs of cell biologists, whose experiments often provide evidence that is not statistical in nature. This review describes some of the basic statistical principles that may be of use to experimental biologists, but it does not cover the sophisticated statistics needed for papers that contain evidence of no other kind. PMID:25000992
... cancer statistics across the world. U.S. Cancer Mortality Trends The best indicator of progress against cancer is ... the number of cancer survivors has increased. These trends show that progress is being made against the ...
The Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute works to provide information on cancer statistics in an effort to reduce the burden of cancer among the U.S. population.
NASA Astrophysics Data System (ADS)
Hermann, Claudine
Statistical Physics bridges the properties of a macroscopic system and the microscopic behavior of its constituting particles, otherwise impossible due to the giant magnitude of Avogadro's number. Numerous systems of today's key technologies - such as semiconductors or lasers - are macroscopic quantum objects; only statistical physics allows for understanding their fundamentals. Therefore, this graduate text also focuses on particular applications such as the properties of electrons in solids with applications, and radiation thermodynamics and the greenhouse effect.
Automatic interpretation of biological tests.
Boufriche-Boufaïda, Z
1998-03-01
In this article, an approach for an Automatic Interpretation of Biological Tests (AIBT) is described. The developed system is much needed in Preventive Medicine Centers (PMCs). It is designed as a self-sufficient system that could be easily used by trained nurses during the routine visit. The results that the system provides are not only useful to provide the PMC physicians with a preliminary diagnosis, but also allows them more time to focus on the serious cases, making the clinical visit more qualitative. On the other hand, because the use of such a system has been planned for many years, its possibilities for future extensions must be seriously considered. The methodology adopted can be interpreted as a combination of the advantages of two main approaches adopted in current diagnostic systems: the production system approach and the object-oriented system approach. From the rules, the ability of these approaches to capture the deductive processes of the expert in domains where causal mechanisms are often understood are retained. The object-oriented approach guides the elicitation and the engineering of knowledge in such a way that abstractions, categorizations and classifications are encouraged whilst individual instances of objects of any type are recognized as separate, independent entities. PMID:9684093
NASA Astrophysics Data System (ADS)
Goodman, J. W.
This book is based on the thesis that some training in the area of statistical optics should be included as a standard part of any advanced optics curriculum. Random variables are discussed, taking into account definitions of probability and random variables, distribution functions and density functions, an extension to two or more random variables, statistical averages, transformations of random variables, sums of real random variables, Gaussian random variables, complex-valued random variables, and random phasor sums. Other subjects examined are related to random processes, some first-order properties of light waves, the coherence of optical waves, some problems involving high-order coherence, effects of partial coherence on imaging systems, imaging in the presence of randomly inhomogeneous media, and fundamental limits in photoelectric detection of light. Attention is given to deterministic versus statistical phenomena and models, the Fourier transform, and the fourth-order moment of the spectrum of a detected speckle image.
ERIC Educational Resources Information Center
Christensen, Timothy J.; Labov, Jay B.
1997-01-01
Details the construction of a viewing chamber for fruit flies that connects to a dissecting microscope and features a design that enables students to easily move fruit flies in and out of the chamber. (DDR)
Misuse of statistics in surgical literature.
Thiese, Matthew S; Ronna, Brenden; Robbins, Riann B
2016-08-01
Statistical analyses are a key part of biomedical research. Traditionally surgical research has relied upon a few statistical methods for evaluation and interpretation of data to improve clinical practice. As research methods have increased in both rigor and complexity, statistical analyses and interpretation have fallen behind. Some evidence suggests that surgical research studies are being designed and analyzed improperly given the specific study question. The goal of this article is to discuss the complexities of surgical research analyses and interpretation, and provide some resources to aid in these processes. PMID:27621909
Misuse of statistics in surgical literature
Ronna, Brenden; Robbins, Riann B.
2016-01-01
Statistical analyses are a key part of biomedical research. Traditionally surgical research has relied upon a few statistical methods for evaluation and interpretation of data to improve clinical practice. As research methods have increased in both rigor and complexity, statistical analyses and interpretation have fallen behind. Some evidence suggests that surgical research studies are being designed and analyzed improperly given the specific study question. The goal of this article is to discuss the complexities of surgical research analyses and interpretation, and provide some resources to aid in these processes.
Interpretation of psychophysics response curves using statistical physics.
Knani, S; Khalfaoui, M; Hachicha, M A; Mathlouthi, M; Ben Lamine, A
2014-05-15
Experimental gustatory curves have been fitted for four sugars (sucrose, fructose, glucose and maltitol), using a double layer adsorption model. Three parameters of the model are fitted, namely the number of molecules per site n, the maximum response RM and the concentration at half saturation C1/2. The behaviours of these parameters are discussed in relationship to each molecule's characteristics. Starting from the double layer adsorption model, we determined (in addition) the adsorption energy of each molecule on taste receptor sites. The use of the threshold expression allowed us to gain information about the adsorption occupation rate of a receptor site which fires a minimal response at a gustatory nerve. Finally, by means of this model we could calculate the configurational entropy of the adsorption system, which can describe the order and disorder of the adsorbent surface. PMID:24423561
The Statistical Literacy Needed to Interpret School Assessment Data
ERIC Educational Resources Information Center
Chick, Helen; Pierce, Robyn
2013-01-01
State-wide and national testing in areas such as literacy and numeracy produces reports containing graphs and tables illustrating school and individual performance. These are intended to inform teachers, principals, and education organisations about student and school outcomes, to guide change and improvement. Given the complexity of the…
ERIC Educational Resources Information Center
Erekson, James A.
2010-01-01
Prosody is a means for "reading with expression" and is one aspect of oral reading competence. This theoretical inquiry asserts that prosody is central to interpreting text, and draws distinctions between "syntactic" prosody (for phrasing) and "emphatic" prosody (for interpretation). While reading with expression appears as a criterion in major…
ERIC Educational Resources Information Center
Chicot, Katie; Holmes, Hilary
2012-01-01
The use, and misuse, of statistics is commonplace, yet in the printed format data representations can be either over simplified, supposedly for impact, or so complex as to lead to boredom, supposedly for completeness and accuracy. In this article the link to the video clip shows how dynamic visual representations can enliven and enhance the…
ERIC Educational Resources Information Center
Catley, Alan
2007-01-01
Following the announcement last year that there will be no more math coursework assessment at General Certificate of Secondary Education (GCSE), teachers will in the future be able to devote more time to preparing learners for formal examinations. One of the key things that the author has learned when teaching statistics is that it makes for far…
Centralised interpretation of electrocardiograms.
Macfarlane, P W; Watts, M P; Lawrie, T D; Walker, R S
1977-01-01
A system was devised so that a peripheral hospital could transmit electrocardiograms (ECGs) to a central computer for interpretation. The link that transmits both ECGs and reports is provided by the telephone network. Initial results showed that telephone transmission did not significantly affect the accuracy of the ECG interpretation. The centralised computer programme could be much more widely used to provide ECG interpretations. A telephone link would not be justified in health centres, where the demand for ECGs is fairly small, but ECGs recorded at a health centre can be sent to the computer for interpretation and returned the next day. The most cost-effective method of providing computer interpretation for several health centres in a large city would be to have a portable electrocardiograph and transmission facilities, which could be moved from centre to centre. PMID:319866
Groen-Blokhuis, Maria M; Middeldorp, Christel M; M van Beijsterveldt, Catharina E; Boomsma, Dorret I
2011-10-01
In order to estimate the influence of genetic and environmental factors on 'crying without a cause' and 'being easily upset' in 2-year-old children, a large twin study was carried out. Prospective data were available for ~18,000 2-year-old twin pairs from the Netherlands Twin Register. A bivariate genetic analysis was performed using structural equation modeling in the Mx software package. The influence of maternal personality characteristics and demographic and lifestyle factors was tested to identify specific risk factors that may underlie the shared environment of twins. Furthermore, it was tested whether crying without a cause and being easily upset were predictive of later internalizing, externalizing and attention problems. Crying without a cause yielded a heritability estimate of 60% in boys and girls. For easily upset, the heritability was estimated at 43% in boys and 31% in girls. The variance explained by shared environment varied between 35% and 63%. The correlation between crying without a cause and easily upset (r = .36) was explained both by genetic and shared environmental factors. Birth cohort, gestational age, socioeconomic status, parental age, parental smoking behavior and alcohol use during pregnancy did not explain the shared environmental component. Neuroticism of the mother explained a small proportion of the additive genetic, but not of the shared environmental effects for easily upset. Crying without a cause and being easily upset at age 2 were predictive of internalizing, externalizing and attention problems at age 7, with effect sizes of .28-.42. A large influence of shared environmental factors on crying without a cause and easily upset was detected. Although these effects could be specific to these items, we could not explain them by personality characteristics of the mother or by demographic and lifestyle factors, and we recognize that these effects may reflect other maternal characteristics. A substantial influence of genetic factors
NASA Technical Reports Server (NTRS)
Owre, Sam; Shankar, Natarajan; Butler, Ricky W. (Technical Monitor)
2001-01-01
The purpose of this task was to provide a mechanism for theory interpretations in a prototype verification system (PVS) so that it is possible to demonstrate the consistency of a theory by exhibiting an interpretation that validates the axioms. The mechanization makes it possible to show that one collection of theories is correctly interpreted by another collection of theories under a user-specified interpretation for the uninterpreted types and constants. A theory instance is generated and imported, while the axiom instances are generated as proof obligations to ensure that the interpretation is valid. Interpretations can be used to show that an implementation is a correct refinement of a specification, that an axiomatically defined specification is consistent, or that a axiomatically defined specification captures its intended models. In addition, the theory parameter mechanism has been extended with a notion of theory as parameter so that a theory instance can be given as an actual parameter to an imported theory. Theory interpretations can thus be used to refine an abstract specification or to demonstrate the consistency of an axiomatic theory. In this report we describe the mechanism in detail. This extension is a part of PVS version 3.0, which will be publicly released in mid-2001.
Statistics Poster Challenge for Schools
ERIC Educational Resources Information Center
Payne, Brad; Freeman, Jenny; Stillman, Eleanor
2013-01-01
The analysis and interpretation of data are important life skills. A poster challenge for schoolchildren provides an innovative outlet for these skills and demonstrates their relevance to daily life. We discuss our Statistics Poster Challenge and the lessons we have learned.
Fit Indices Versus Test Statistics
ERIC Educational Resources Information Center
Yuan, Ke-Hai
2005-01-01
Model evaluation is one of the most important aspects of structural equation modeling (SEM). Many model fit indices have been developed. It is not an exaggeration to say that nearly every publication using the SEM methodology has reported at least one fit index. Most fit indices are defined through test statistics. Studies and interpretation of…
NASA Astrophysics Data System (ADS)
Goodman, Joseph W.
2000-07-01
The Wiley Classics Library consists of selected books that have become recognized classics in their respective fields. With these new unabridged and inexpensive editions, Wiley hopes to extend the life of these important works by making them available to future generations of mathematicians and scientists. Currently available in the Series: T. W. Anderson The Statistical Analysis of Time Series T. S. Arthanari & Yadolah Dodge Mathematical Programming in Statistics Emil Artin Geometric Algebra Norman T. J. Bailey The Elements of Stochastic Processes with Applications to the Natural Sciences Robert G. Bartle The Elements of Integration and Lebesgue Measure George E. P. Box & Norman R. Draper Evolutionary Operation: A Statistical Method for Process Improvement George E. P. Box & George C. Tiao Bayesian Inference in Statistical Analysis R. W. Carter Finite Groups of Lie Type: Conjugacy Classes and Complex Characters R. W. Carter Simple Groups of Lie Type William G. Cochran & Gertrude M. Cox Experimental Designs, Second Edition Richard Courant Differential and Integral Calculus, Volume I RIchard Courant Differential and Integral Calculus, Volume II Richard Courant & D. Hilbert Methods of Mathematical Physics, Volume I Richard Courant & D. Hilbert Methods of Mathematical Physics, Volume II D. R. Cox Planning of Experiments Harold S. M. Coxeter Introduction to Geometry, Second Edition Charles W. Curtis & Irving Reiner Representation Theory of Finite Groups and Associative Algebras Charles W. Curtis & Irving Reiner Methods of Representation Theory with Applications to Finite Groups and Orders, Volume I Charles W. Curtis & Irving Reiner Methods of Representation Theory with Applications to Finite Groups and Orders, Volume II Cuthbert Daniel Fitting Equations to Data: Computer Analysis of Multifactor Data, Second Edition Bruno de Finetti Theory of Probability, Volume I Bruno de Finetti Theory of Probability, Volume 2 W. Edwards Deming Sample Design in Business Research
Interpretation of Biosphere Reserves.
ERIC Educational Resources Information Center
Merriman, Tim
1994-01-01
Introduces the Man and the Biosphere Programme (MAB) to monitor the 193 biogeographical provinces of the Earth and the creation of biosphere reserves. Highlights the need for interpreters to become familiar or involved with MAB program activities. (LZ)
BIOMONITORING: INTERPRETATION AND USES
With advanced technologies, it is now possible to measure very low levels of many chemicals in biological fluids. However, the appropriate use and interpretation of biomarkers will depend upon many factors associated with the exposure, adsorption, deposition, metabolism, and eli...
NASA Astrophysics Data System (ADS)
Burns, T. J.; Swanson, E. S.
2016-09-01
A variety of options for interpreting the DØ state, X (5568), are examined. We find that threshold, cusp, molecular, and tetraquark models are all unfavoured. Several experimental tests for unravelling the nature of the signal are suggested.
Interpretation of Bernoulli's Equation.
ERIC Educational Resources Information Center
Bauman, Robert P.; Schwaneberg, Rolf
1994-01-01
Discusses Bernoulli's equation with regards to: horizontal flow of incompressible fluids, change of height of incompressible fluids, gases, liquids and gases, and viscous fluids. Provides an interpretation, properties, terminology, and applications of Bernoulli's equation. (MVL)
Customizable tool for ecological data entry, assessment, monitoring, and interpretation
Technology Transfer Automated Retrieval System (TEKTRAN)
The Database for Inventory, Monitoring and Assessment (DIMA) is a highly customizable tool for data entry, assessment, monitoring, and interpretation. DIMA is a Microsoft Access database that can easily be used without Access knowledge and is available at no cost. Data can be entered for common, nat...
Interpreter-mediated dentistry.
Bridges, Susan; Drew, Paul; Zayts, Olga; McGrath, Colman; Yiu, Cynthia K Y; Wong, H M; Au, T K F
2015-05-01
The global movements of healthcare professionals and patient populations have increased the complexities of medical interactions at the point of service. This study examines interpreter mediated talk in cross-cultural general dentistry in Hong Kong where assisting para-professionals, in this case bilingual or multilingual Dental Surgery Assistants (DSAs), perform the dual capabilities of clinical assistant and interpreter. An initial language use survey was conducted with Polyclinic DSAs (n = 41) using a logbook approach to provide self-report data on language use in clinics. Frequencies of mean scores using a 10-point visual analogue scale (VAS) indicated that the majority of DSAs spoke mainly Cantonese in clinics and interpreted for postgraduates and professors. Conversation Analysis (CA) examined recipient design across a corpus (n = 23) of video-recorded review consultations between non-Cantonese speaking expatriate dentists and their Cantonese L1 patients. Three patterns of mediated interpreting indicated were: dentist designated expansions; dentist initiated interpretations; and assistant initiated interpretations to both the dentist and patient. The third, rather than being perceived as negative, was found to be framed either in response to patient difficulties or within the specific task routines of general dentistry. The findings illustrate trends in dentistry towards personalized care and patient empowerment as a reaction to product delivery approaches to patient management. Implications are indicated for both treatment adherence and the education of dental professionals. PMID:25828074
NASA Astrophysics Data System (ADS)
Altarelli, Fabrizio; Monasson, Rémi; Zamponi, Francesco
2007-02-01
For large clause-to-variable ratios, typical K-SAT instances drawn from the uniform distribution have no solution. We argue, based on statistical mechanics calculations using the replica and cavity methods, that rare satisfiable instances from the uniform distribution are very similar to typical instances drawn from the so-called planted distribution, where instances are chosen uniformly between the ones that admit a given solution. It then follows, from a recent article by Feige, Mossel and Vilenchik (2006 Complete convergence of message passing algorithms for some satisfiability problems Proc. Random 2006 pp 339-50), that these rare instances can be easily recognized (in O(log N) time and with probability close to 1) by a simple message-passing algorithm.
1986-01-01
Official population data for the USSR are presented for 1985 and 1986. Part 1 (pp. 65-72) contains data on capitals of union republics and cities with over one million inhabitants, including population estimates for 1986 and vital statistics for 1985. Part 2 (p. 72) presents population estimates by sex and union republic, 1986. Part 3 (pp. 73-6) presents data on population growth, including birth, death, and natural increase rates, 1984-1985; seasonal distribution of births and deaths; birth order; age-specific birth rates in urban and rural areas and by union republic; marriages; age at marriage; and divorces. PMID:12178831
NASA Technical Reports Server (NTRS)
Firstenberg, H.
1971-01-01
The statistics are considered of the Monte Carlo method relative to the interpretation of the NUGAM2 and NUGAM3 computer code results. A numerical experiment using the NUGAM2 code is presented and the results are statistically interpreted.
NASA Astrophysics Data System (ADS)
Tarolli, Paolo; Prosdocimi, Massimo; Sofia, Giulia; Dalla Fontana, Giancarlo
2015-04-01
A real opportunity and challenge for the hazard mapping is offered by the use of smartphones and low-cost and flexible photogrammetric technique (i.e. 'Structure-from-Motion'-SfM-). Differently from the other traditional photogrammetric methods, the SfM allows to reconstitute three-dimensional geometries (Digital Surface Models, DSMs) from randomly acquired images. The images can be acquired by standalone digital cameras (compact or reflex), or even by smartphones built-in cameras. This represents a "revolutionary" advance compared with more expensive technologies and applications (e.g. Terrestrial Laser Scanner TLS, airborne lidar) (Tarolli, 2014). Through fast, simple and consecutive field surveys, anyone with a smartphone can take a lot of pictures of the same study area. This way, high-resolution and multi-temporal DSMs may be obtained and used to better monitor and understand erosion and deposition processes. Furthermore, these topographic data can also facilitate to quantify volumes of eroded materials due to landslides and recognize the major critical issues that usually occur during a natural hazard (e.g. river bank erosion and/or collapse due to floods). In this work we considered different case studies located in different environmental contexts of Italy, where extensive photosets were obtained using smartphones. TLS data were also considered in the analysis as benchmark to compare with SfM data. Digital Surface Models (DSMs) derived from SfM at centimeter grid-cell resolution revealed to be effective to automatically recognize areas subject to surface instabilities, and estimate quantitatively erosion and deposition volumes, for example. Morphometric indexes such as landform curvature and surface roughness, and statistical thresholds (e.g. standard deviation) of these indices, served as the basis for the proposed analyses. The results indicate that SfM technique through smartphones really offers a fast, simple and affordable alternative to lidar
NASA Technical Reports Server (NTRS)
Mc Crae, A. W., Jr.
1967-01-01
Multiconductor instrumentation cable in which the conducting wires are routed through two concentric copper tube sheaths, employing a compressed insulator between the conductors and between the inner and outer sheaths, is durable and easily installed in high thermal or nuclear radiation area. The double sheath is a barrier against moisture, abrasion, and vibration.
SOCR: Statistics Online Computational Resource
Dinov, Ivo D.
2011-01-01
The need for hands-on computer laboratory experience in undergraduate and graduate statistics education has been firmly established in the past decade. As a result a number of attempts have been undertaken to develop novel approaches for problem-driven statistical thinking, data analysis and result interpretation. In this paper we describe an integrated educational web-based framework for: interactive distribution modeling, virtual online probability experimentation, statistical data analysis, visualization and integration. Following years of experience in statistical teaching at all college levels using established licensed statistical software packages, like STATA, S-PLUS, R, SPSS, SAS, Systat, etc., we have attempted to engineer a new statistics education environment, the Statistics Online Computational Resource (SOCR). This resource performs many of the standard types of statistical analysis, much like other classical tools. In addition, it is designed in a plug-in object-oriented architecture and is completely platform independent, web-based, interactive, extensible and secure. Over the past 4 years we have tested, fine-tuned and reanalyzed the SOCR framework in many of our undergraduate and graduate probability and statistics courses and have evidence that SOCR resources build student’s intuition and enhance their learning. PMID:21451741
Hold My Calls: An Activity for Introducing the Statistical Process
ERIC Educational Resources Information Center
Abel, Todd; Poling, Lisa
2015-01-01
Working with practicing teachers, this article demonstrates, through the facilitation of a statistical activity, how to introduce and investigate the unique qualities of the statistical process including: formulate a question, collect data, analyze data, and interpret data.
NASA Astrophysics Data System (ADS)
Fink, Thomas
2015-03-01
We introduce a simple class of distribution networks which withstand damage by being repairable instead of redundant. Instead of asking how hard it is to disconnect nodes through damage, we ask how easy it is to reconnect nodes after damage. We prove that optimal networks on regular lattices have an expected cost of reconnection proportional to the lattice length, and that such networks have exactly three levels of structural hierarchy. We extend our results to networks subject to repeated attacks, in which the repairs themselves must be repairable. We find that, in exchange for a modest increase in repair cost, such networks are able to withstand any number of attacks. We acknowledge support from the Defense Threat Reduction Agency, BCG and EU FP7 (Growthcom).
Copenhagen and Transactional Interpretations
NASA Astrophysics Data System (ADS)
Görnitz, Th.; von Weizsäcker, C. F.
1988-02-01
The Copenhagen interpretation (CI) never received an authoritative codification. It was a “minimum semantics” of quantum mechanics. We assume that it expresses a theory identical with the Transactional Interpretation (TI) when the observer is included into the system described by the theory. A theory consists of a mathematical structure with a physical semantics. Now, CI rests on an implicit description of the modes of time which is also presupposed by the Second Law of Thermodynamics. Essential is the futuric meaning of probability as a prediction of a relative frequency. CI can be shown to be fully consistent on this basis. The TI and CI can be translated into each other by a simple “dictionary.” The TI describes all events as CI describes past events; CI calls future events possibilities, which TI treats like facts. All predictions of both interpretations agree; we suppose the difference to be linguistic.
Hospitals as interpretation systems.
Thomas, J B; McDaniel, R R; Anderson, R A
1991-01-01
In this study of 162 hospitals, it was found that the chief executive officer's (CEO's) interpretation of strategic issues is related to the existing hospital strategy and the hospital's information processing structure. Strategy was related to interpretation in terms of the extent to which a given strategic issue was perceived as controllable or uncontrollable. Structure was related to the extent to which an issue was defined as positive or negative, was labeled as controllable or uncontrollable, and was perceived as leading to a gain or a loss. Together, strategy and structure accounted for a significant part of the variance in CEO interpretations of strategic events. The theoretical and managerial implications of these findings are discussed. PMID:1991677
Statistics in fusion experiments
NASA Astrophysics Data System (ADS)
McNeill, D. H.
1997-11-01
Since the reasons for the variability in data from plasma experiments are often unknown or uncontrollable, statistical methods must be applied. Reliable interpretation and public accountability require full data sets. Two examples of data misrepresentation at PPPL are analyzed: Te >100 eV on S-1 spheromak.(M. Yamada, Nucl. Fusion 25, 1327 (1985); reports to DoE; etc.) The reported high values (statistical artifacts of Thomson scattering measurements) were selected from a mass of data with an average of 40 eV or less. ``Correlated'' spectroscopic data were meaningless. (2) Extrapolation to Q >=0.5 for DT in TFTR.(D. Meade et al., IAEA Baltimore (1990), V. 1, p. 9; H. P. Furth, Statements to U. S. Congress (1989).) The DD yield used there was the highest through 1990 (>= 50% above average) and the DT to DD power ratio used was about twice any published value. Average DD yields and published yield ratios scale to Q<0.15 for DT, in accord with the observed performance over the last 3 1/2 years. Press reports of outlier data from TFTR have obscured the fact that the DT behavior follows from trivial scaling of the DD data. Good practice in future fusion research would have confidence intervals and other descriptive statistics accompanying reported numerical values (cf. JAMA).
The National Lakes Assessment (NLA) and other lake survey and monitoring efforts increasingly rely upon biological assemblage data to define lake condition. Information concerning the multiple dimensions of physical and chemical habitat is necessary to interpret this biological ...
The ADAMS interactive interpreter
Rietscha, E.R.
1990-12-17
The ADAMS (Advanced DAta Management System) project is exploring next generation database technology. Database management does not follow the usual programming paradigm. Instead, the database dictionary provides an additional name space environment that should be interactively created and tested before writing application code. This document describes the implementation and operation of the ADAMS Interpreter, an interactive interface to the ADAMS data dictionary and runtime system. The Interpreter executes individual statements of the ADAMS Interface Language, providing a fast, interactive mechanism to define and access persistent databases. 5 refs.
How to spot a statistical problem: advice for a non-statistical reviewer.
Greenwood, Darren C; Freeman, Jennifer V
2015-01-01
Statistical analyses presented in general medical journals are becoming increasingly sophisticated. BMC Medicine relies on subject reviewers to indicate when a statistical review is required. We consider this policy and provide guidance on when to recommend a manuscript for statistical evaluation. Indicators for statistical review include insufficient detail in methods or results, some common statistical issues and interpretation not based on the presented evidence. Reviewers are required to ensure that the manuscript is methodologically sound and clearly written. Within that context, they are expected to provide constructive feedback and opinion on the statistical design, analysis, presentation and interpretation. If reviewers lack the appropriate background to positively confirm the appropriateness of any of the manuscript's statistical aspects, they are encouraged to recommend it for expert statistical review. PMID:26521808
INCREASING SCIENTIFIC POWER WITH STATISTICAL POWER
A brief survey of basic ideas in statistical power analysis demonstrates the advantages and ease of using power analysis throughout the design, analysis, and interpretation of research. he power of a statistical test is the probability of rejecting the null hypothesis of the test...
Screencast Tutorials Enhance Student Learning of Statistics
ERIC Educational Resources Information Center
Lloyd, Steven A.; Robertson, Chuck L.
2012-01-01
Although the use of computer-assisted instruction has rapidly increased, there is little empirical research evaluating these technologies, specifically within the context of teaching statistics. The authors assessed the effect of screencast tutorials on learning outcomes, including statistical knowledge, application, and interpretation. Students…
Explaining the Interpretive Mind.
ERIC Educational Resources Information Center
Brockmeier, Jens
1996-01-01
Examines two prominent positions in the epistemological foundations of psychology--Piaget's causal explanatory claims and Vygotsky's interpretive understanding; contends that they need to be placed in their wider philosophical contexts. Argues that the danger of causally explaining cultural practices through which human beings construct and…
Interpreting the Constitution.
ERIC Educational Resources Information Center
Brennan, William J., Jr.
1987-01-01
Discusses constitutional interpretations relating to capital punishment and protection of human dignity. Points out the document's effectiveness in creating a new society by adapting its principles to current problems and needs. Considers two views of the Constitution that lead to controversy over the legitimacy of judicial decisions. (PS)
Interpreting & Biomechanics. PEPNet Tipsheet
ERIC Educational Resources Information Center
PEPNet-Northeast, 2001
2001-01-01
Cumulative trauma disorder (CTD) refers to a collection of disorders associated with nerves, muscles, tendons, bones, and the neurovascular (nerves and related blood vessels) system. CTD symptoms may involve the neck, back, shoulders, arms, wrists, or hands. Interpreters with CTD may experience a variety of symptoms including: pain, joint…
Listening and Message Interpretation
ERIC Educational Resources Information Center
Edwards, Renee
2011-01-01
Message interpretation, the notion that individuals assign meaning to stimuli, is related to listening presage, listening process, and listening product. As a central notion of communication, meaning includes (a) denotation and connotation, and (b) content and relational meanings, which can vary in ambiguity and vagueness. Past research on message…
Social Maladjustment: An Interpretation.
ERIC Educational Resources Information Center
Center, David B.
The exclusionary term, "social maladjustment," the definition in Public Law 94-142 (the Education for All Handicapped Children Act) of serious emotional disturbance, has been an enigma for special education. This paper attempts to limit the interpretation of social maladjustment in order to counter effects of such decisions as "Honig vs. Doe" in…
Abstract Interpreters for Free
NASA Astrophysics Data System (ADS)
Might, Matthew
In small-step abstract interpretations, the concrete and abstract semantics bear an uncanny resemblance. In this work, we present an analysis-design methodology that both explains and exploits that resemblance. Specifically, we present a two-step method to convert a small-step concrete semantics into a family of sound, computable abstract interpretations. The first step re-factors the concrete state-space to eliminate recursive structure; this refactoring of the state-space simultaneously determines a store-passing-style transformation on the underlying concrete semantics. The second step uses inference rules to generate an abstract state-space and a Galois connection simultaneously. The Galois connection allows the calculation of the "optimal" abstract interpretation. The two-step process is unambiguous, but nondeterministic: at each step, analysis designers face choices. Some of these choices ultimately influence properties such as flow-, field- and context-sensitivity. Thus, under the method, we can give the emergence of these properties a graph-theoretic characterization. To illustrate the method, we systematically abstract the continuation-passing style lambda calculus to arrive at two distinct families of analyses. The first is the well-known k-CFA family of analyses. The second consists of novel "environment-centric" abstract interpretations, none of which appear in the literature on static analysis of higher-order programs.
ERIC Educational Resources Information Center
Layton, Lyn; Miller, Carol
2004-01-01
The National Literacy Strategy (NLS) was introduced into schools in England in 1998 with the aim of raising the literacy attainments of primary-aged children. The Framework for Teaching the Literacy Hour, a key component of the NLS, proposes an interpretation of literacy that emphasises reading, writing and spelling skills. An investigation of the…
Kim, Youngwoo; Woo, Kyoohee; Kim, Inhyuk; Cho, Yong Soo; Jeong, Sunho; Moon, Jooho
2013-11-01
Among various candidate materials, Cu2ZnSnS4 (CZTS) is a promising earth-abundant semiconductor for low-cost thin film solar cells. We report a facile, less toxic, highly concentrated synthetic method utilizing the heretofore unrecognized, easily decomposable capping ligand of triphenylphosphate, where phase-pure, single-crystalline, and well-dispersed colloidal CZTS nanocrystals were obtained. The favorable influence of the easily decomposable capping ligand on the microstructural evolution of device-quality CZTS absorber layers was clarified based on a comparative study with commonly used oleylamine-capped CZTS nanoparticles. The resulting CZTS nanoparticles enabled us to produce a dense and crack-free absorbing layer through annealing under a N2 + H2S (4%) atmosphere, demonstrating a solar cell with an efficiency of 3.6% under AM 1.5 illumination. PMID:24057000
Linking numbers, spin, and statistics of solitons
NASA Technical Reports Server (NTRS)
Wilczek, F.; Zee, A.
1983-01-01
The spin and statistics of solitons in the (2 + 1)- and (3 + 1)-dimensional nonlinear sigma models is considered. For the (2 + 1)-dimensional case, there is the possibility of fractional spin and exotic statistics; for 3 + 1 dimensions, the usual spin-statistics relation is demonstrated. The linking-number interpretation of the Hopf invariant and the use of suspension considerably simplify the analysis.
Ranald Macdonald and statistical inference.
Smith, Philip T
2009-05-01
Ranald Roderick Macdonald (1945-2007) was an important contributor to mathematical psychology in the UK, as a referee and action editor for British Journal of Mathematical and Statistical Psychology and as a participant and organizer at the British Psychological Society's Mathematics, statistics and computing section meetings. This appreciation argues that his most important contribution was to the foundations of significance testing, where his concern about what information was relevant in interpreting the results of significance tests led him to be a persuasive advocate for the 'Weak Fisherian' form of hypothesis testing. PMID:19351454
Evaluation of Psychotherapeutic Interpretations
POGGE, DAVID L.; DOUGHER, MICHAEL J.
1992-01-01
If much psychotherapy literature goes unread and unused by therapists, one reason may be the apparent irrelevance of theory-derived hypotheses to actual practice. Methods that uncover tacit knowledge that practicing therapists already possess can provide the empirical basis for more relevant theories and the testing of more meaningful hypotheses. This study demonstrates application of the phenomenological method to the question of evaluating psychotherapy. To discover how experienced psychotherapists evaluate interpretations made in actual psychotherapy sessions, therapists were asked to evaluate such interpretations from videotapes; analysis of responses yielded a set of 10 dimensions of evaluation. Such methods offer both practical utility and a source of theoretical growth anchored in the real world of the practicing therapist. PMID:22700101
Semantic interpretation of nominalizations
Hull, R.D.; Gomez, F.
1996-12-31
A computational approach to the semantic interpretation of nominalizations is described. Interpretation of normalizations involves three tasks: deciding whether the normalization is being used in a verbal or non-verbal sense; disambiguating the normalized verb when a verbal sense is used; and determining the fillers of the thematic roles of the verbal concept or predicate of the nominalization. A verbal sense can be recognized by the presence of modifiers that represent the arguments of the verbal concept. It is these same modifiers which provide the semantic clues to disambiguate the normalized verb. In the absence of explicit modifiers, heuristics are used to discriminate between verbal and non-verbal senses. A correspondence between verbs and their nominalizations is exploited so that only a small amount of additional knowledge is needed to handle the nominal form. These methods are tested in the domain of encyclopedic texts and the results are shown.
Interpreting uncertainty terms.
Holtgraves, Thomas
2014-08-01
Uncertainty terms (e.g., some, possible, good, etc.) are words that do not have a fixed referent and hence are relatively ambiguous. A model is proposed that specifies how, from the hearer's perspective, recognition of facework as a potential motive for the use of an uncertainty term results in a calibration of the intended meaning of that term. Four experiments are reported that examine the impact of face threat, and the variables that affect it (e.g., power), on the manner in which a variety of uncertainty terms (probability terms, quantifiers, frequency terms, etc.) are interpreted. Overall, the results demonstrate that increased face threat in a situation will result in a more negative interpretation of an utterance containing an uncertainty term. That the interpretation of so many different types of uncertainty terms is affected in the same way suggests the operation of a fundamental principle of language use, one with important implications for the communication of risk, subjective experience, and so on. PMID:25090127
Cancer survival: an overview of measures, uses, and interpretation.
Mariotto, Angela B; Noone, Anne-Michelle; Howlader, Nadia; Cho, Hyunsoon; Keel, Gretchen E; Garshell, Jessica; Woloshin, Steven; Schwartz, Lisa M
2014-11-01
Survival statistics are of great interest to patients, clinicians, researchers, and policy makers. Although seemingly simple, survival can be confusing: there are many different survival measures with a plethora of names and statistical methods developed to answer different questions. This paper aims to describe and disseminate different survival measures and their interpretation in less technical language. In addition, we introduce templates to summarize cancer survival statistic organized by their specific purpose: research and policy versus prognosis and clinical decision making. PMID:25417231