Statistically significant relational data mining :

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berry, Jonathan W.; Leung, Vitus Joseph; Phillips, Cynthia Ann

This report summarizes the work performed under the project (3z(BStatitically significant relational data mining.(3y (BThe goal of the project was to add more statistical rigor to the fairly ad hoc area of data mining on graphs. Our goal was to develop better algorithms and better ways to evaluate algorithm quality. We concetrated on algorithms for community detection, approximate pattern matching, and graph similarity measures. Approximate pattern matching involves finding an instance of a relatively small pattern, expressed with tolerance, in a large graph of data observed with uncertainty. This report gathers the abstracts and references for the eight refereed publicationsmore » that have appeared as part of this work. We then archive three pieces of research that have not yet been published. The first is theoretical and experimental evidence that a popular statistical measure for comparison of community assignments favors over-resolved communities over approximations to a ground truth. The second are statistically motivated methods for measuring the quality of an approximate match of a small pattern in a large graph. The third is a new probabilistic random graph model. Statisticians favor these models for graph analysis. The new local structure graph model overcomes some of the issues with popular models such as exponential random graph models and latent variable models.« less

Précis of statistical significance: rationale, validity, and utility.

PubMed

Chow, S L

1998-04-01

The null-hypothesis significance-test procedure (NHSTP) is defended in the context of the theory-corroboration experiment, as well as the following contrasts: (a) substantive hypotheses versus statistical hypotheses, (b) theory corroboration versus statistical hypothesis testing, (c) theoretical inference versus statistical decision, (d) experiments versus nonexperimental studies, and (e) theory corroboration versus treatment assessment. The null hypothesis can be true because it is the hypothesis that errors are randomly distributed in data. Moreover, the null hypothesis is never used as a categorical proposition. Statistical significance means only that chance influences can be excluded as an explanation of data; it does not identify the nonchance factor responsible. The experimental conclusion is drawn with the inductive principle underlying the experimental design. A chain of deductive arguments gives rise to the theoretical conclusion via the experimental conclusion. The anomalous relationship between statistical significance and the effect size often used to criticize NHSTP is more apparent than real. The absolute size of the effect is not an index of evidential support for the substantive hypothesis. Nor is the effect size, by itself, informative as to the practical importance of the research result. Being a conditional probability, statistical power cannot be the a priori probability of statistical significance. The validity of statistical power is debatable because statistical significance is determined with a single sampling distribution of the test statistic based on H0, whereas it takes two distributions to represent statistical power or effect size. Sample size should not be determined in the mechanical manner envisaged in power analysis. It is inappropriate to criticize NHSTP for nonstatistical reasons. At the same time, neither effect size, nor confidence interval estimate, nor posterior probability can be used to exclude chance as an explanation of

The Use of Meta-Analytic Statistical Significance Testing

ERIC Educational Resources Information Center

Polanin, Joshua R.; Pigott, Terri D.

2015-01-01

Meta-analysis multiplicity, the concept of conducting multiple tests of statistical significance within one review, is an underdeveloped literature. We address this issue by considering how Type I errors can impact meta-analytic results, suggest how statistical power may be affected through the use of multiplicity corrections, and propose how…

Common pitfalls in statistical analysis: “P” values, statistical significance and confidence intervals

PubMed Central

Ranganathan, Priya; Pramesh, C. S.; Buyse, Marc

2015-01-01

In the second part of a series on pitfalls in statistical analysis, we look at various ways in which a statistically significant study result can be expressed. We debunk some of the myths regarding the ‘P’ value, explain the importance of ‘confidence intervals’ and clarify the importance of including both values in a paper PMID:25878958

Student and Teacher Factors as Predictors of Statistics Achievement in Federal School of Statistics Ibadan

ERIC Educational Resources Information Center

Adetona, Abel Adekanmi

2017-01-01

The study aimed at assessing how students and teachers factor taken together influence students' achievement in Statistics as well as their relative contribution to the prediction. Two research questions were raised and purposive sampling was adopted to select national diploma year 2 students since they are already in their final level in the…

Finding Statistically Significant Communities in Networks

PubMed Central

Lancichinetti, Andrea; Radicchi, Filippo; Ramasco, José J.; Fortunato, Santo

2011-01-01

Community structure is one of the main structural features of networks, revealing both their internal organization and the similarity of their elementary units. Despite the large variety of methods proposed to detect communities in graphs, there is a big need for multi-purpose techniques, able to handle different types of datasets and the subtleties of community structure. In this paper we present OSLOM (Order Statistics Local Optimization Method), the first method capable to detect clusters in networks accounting for edge directions, edge weights, overlapping communities, hierarchies and community dynamics. It is based on the local optimization of a fitness function expressing the statistical significance of clusters with respect to random fluctuations, which is estimated with tools of Extreme and Order Statistics. OSLOM can be used alone or as a refinement procedure of partitions/covers delivered by other techniques. We have also implemented sequential algorithms combining OSLOM with other fast techniques, so that the community structure of very large networks can be uncovered. Our method has a comparable performance as the best existing algorithms on artificial benchmark graphs. Several applications on real networks are shown as well. OSLOM is implemented in a freely available software (http://www.oslom.org), and we believe it will be a valuable tool in the analysis of networks. PMID:21559480

Statistical significance of combinatorial regulations

PubMed Central

Terada, Aika; Okada-Hatakeyama, Mariko; Tsuda, Koji; Sese, Jun

2013-01-01

More than three transcription factors often work together to enable cells to respond to various signals. The detection of combinatorial regulation by multiple transcription factors, however, is not only computationally nontrivial but also extremely unlikely because of multiple testing correction. The exponential growth in the number of tests forces us to set a strict limit on the maximum arity. Here, we propose an efficient branch-and-bound algorithm called the “limitless arity multiple-testing procedure” (LAMP) to count the exact number of testable combinations and calibrate the Bonferroni factor to the smallest possible value. LAMP lists significant combinations without any limit, whereas the family-wise error rate is rigorously controlled under the threshold. In the human breast cancer transcriptome, LAMP discovered statistically significant combinations of as many as eight binding motifs. This method may contribute to uncover pathways regulated in a coordinated fashion and find hidden associations in heterogeneous data. PMID:23882073

Assigning statistical significance to proteotypic peptides via database searches

PubMed Central

Alves, Gelio; Ogurtsov, Aleksey Y.; Yu, Yi-Kuo

2011-01-01

Querying MS/MS spectra against a database containing only proteotypic peptides reduces data analysis time due to reduction of database size. Despite the speed advantage, this search strategy is challenged by issues of statistical significance and coverage. The former requires separating systematically significant identifications from less confident identifications, while the latter arises when the underlying peptide is not present, due to single amino acid polymorphisms (SAPs) or post-translational modifications (PTMs), in the proteotypic peptide libraries searched. To address both issues simultaneously, we have extended RAId’s knowledge database to include proteotypic information, utilized RAId’s statistical strategy to assign statistical significance to proteotypic peptides, and modified RAId’s programs to allow for consideration of proteotypic information during database searches. The extended database alleviates the coverage problem since all annotated modifications, even those occurred within proteotypic peptides, may be considered. Taking into account the likelihoods of observation, the statistical strategy of RAId provides accurate E-value assignments regardless whether a candidate peptide is proteotypic or not. The advantage of including proteotypic information is evidenced by its superior retrieval performance when compared to regular database searches. PMID:21055489

Determining the Statistical Significance of Relative Weights

ERIC Educational Resources Information Center

Tonidandel, Scott; LeBreton, James M.; Johnson, Jeff W.

2009-01-01

Relative weight analysis is a procedure for estimating the relative importance of correlated predictors in a regression equation. Because the sampling distribution of relative weights is unknown, researchers using relative weight analysis are unable to make judgments regarding the statistical significance of the relative weights. J. W. Johnson…

A Meta-analysis of Gender Differences in Applied Statistics Achievement.

ERIC Educational Resources Information Center

Schram, Christine M.

1996-01-01

A meta-analysis of gender differences examined statistics achievement in postsecondary level psychology, education, and business courses. Analysis of 13 articles (18 samples) found that undergraduate males had an advantage, outscoring females when the outcome was a series of examinations. Females outscored males when the outcome was total course…

How many spectral lines are statistically significant?

NASA Astrophysics Data System (ADS)

Freund, J.

When experimental line spectra are fitted with least squares techniques one frequently does not know whether n or n + 1 lines may be fitted safely. This paper shows how an F-test can be applied in order to determine the statistical significance of including an extra line into the fitting routine.

Statistical significance test for transition matrices of atmospheric Markov chains

NASA Technical Reports Server (NTRS)

Vautard, Robert; Mo, Kingtse C.; Ghil, Michael

1990-01-01

Low-frequency variability of large-scale atmospheric dynamics can be represented schematically by a Markov chain of multiple flow regimes. This Markov chain contains useful information for the long-range forecaster, provided that the statistical significance of the associated transition matrix can be reliably tested. Monte Carlo simulation yields a very reliable significance test for the elements of this matrix. The results of this test agree with previously used empirical formulae when each cluster of maps identified as a distinct flow regime is sufficiently large and when they all contain a comparable number of maps. Monte Carlo simulation provides a more reliable way to test the statistical significance of transitions to and from small clusters. It can determine the most likely transitions, as well as the most unlikely ones, with a prescribed level of statistical significance.

Advances in Testing the Statistical Significance of Mediation Effects

ERIC Educational Resources Information Center

Mallinckrodt, Brent; Abraham, W. Todd; Wei, Meifen; Russell, Daniel W.

2006-01-01

P. A. Frazier, A. P. Tix, and K. E. Barron (2004) highlighted a normal theory method popularized by R. M. Baron and D. A. Kenny (1986) for testing the statistical significance of indirect effects (i.e., mediator variables) in multiple regression contexts. However, simulation studies suggest that this method lacks statistical power relative to some…

Statistically significant performance results of a mine detector and fusion algorithm from an x-band high-resolution SAR

NASA Astrophysics Data System (ADS)

Williams, Arnold C.; Pachowicz, Peter W.

2004-09-01

Current mine detection research indicates that no single sensor or single look from a sensor will detect mines/minefields in a real-time manner at a performance level suitable for a forward maneuver unit. Hence, the integrated development of detectors and fusion algorithms are of primary importance. A problem in this development process has been the evaluation of these algorithms with relatively small data sets, leading to anecdotal and frequently over trained results. These anecdotal results are often unreliable and conflicting among various sensors and algorithms. Consequently, the physical phenomena that ought to be exploited and the performance benefits of this exploitation are often ambiguous. The Army RDECOM CERDEC Night Vision Laboratory and Electron Sensors Directorate has collected large amounts of multisensor data such that statistically significant evaluations of detection and fusion algorithms can be obtained. Even with these large data sets care must be taken in algorithm design and data processing to achieve statistically significant performance results for combined detectors and fusion algorithms. This paper discusses statistically significant detection and combined multilook fusion results for the Ellipse Detector (ED) and the Piecewise Level Fusion Algorithm (PLFA). These statistically significant performance results are characterized by ROC curves that have been obtained through processing this multilook data for the high resolution SAR data of the Veridian X-Band radar. We discuss the implications of these results on mine detection and the importance of statistical significance, sample size, ground truth, and algorithm design in performance evaluation.

Assessment of statistical significance and clinical relevance.

PubMed

Kieser, Meinhard; Friede, Tim; Gondan, Matthias

2013-05-10

In drug development, it is well accepted that a successful study will demonstrate not only a statistically significant result but also a clinically relevant effect size. Whereas standard hypothesis tests are used to demonstrate the former, it is less clear how the latter should be established. In the first part of this paper, we consider the responder analysis approach and study the performance of locally optimal rank tests when the outcome distribution is a mixture of responder and non-responder distributions. We find that these tests are quite sensitive to their planning assumptions and have therefore not really any advantage over standard tests such as the t-test and the Wilcoxon-Mann-Whitney test, which perform overall well and can be recommended for applications. In the second part, we present a new approach to the assessment of clinical relevance based on the so-called relative effect (or probabilistic index) and derive appropriate sample size formulae for the design of studies aiming at demonstrating both a statistically significant and clinically relevant effect. Referring to recent studies in multiple sclerosis, we discuss potential issues in the application of this approach. Copyright © 2012 John Wiley & Sons, Ltd.

Increasing the statistical significance of entanglement detection in experiments.

PubMed

Jungnitsch, Bastian; Niekamp, Sönke; Kleinmann, Matthias; Gühne, Otfried; Lu, He; Gao, Wei-Bo; Chen, Yu-Ao; Chen, Zeng-Bing; Pan, Jian-Wei

2010-05-28

Entanglement is often verified by a violation of an inequality like a Bell inequality or an entanglement witness. Considerable effort has been devoted to the optimization of such inequalities in order to obtain a high violation. We demonstrate theoretically and experimentally that such an optimization does not necessarily lead to a better entanglement test, if the statistical error is taken into account. Theoretically, we show for different error models that reducing the violation of an inequality can improve the significance. Experimentally, we observe this phenomenon in a four-photon experiment, testing the Mermin and Ardehali inequality for different levels of noise. Furthermore, we provide a way to develop entanglement tests with high statistical significance.

Testing the Difference of Correlated Agreement Coefficients for Statistical Significance

ERIC Educational Resources Information Center

Gwet, Kilem L.

2016-01-01

This article addresses the problem of testing the difference between two correlated agreement coefficients for statistical significance. A number of authors have proposed methods for testing the difference between two correlated kappa coefficients, which require either the use of resampling methods or the use of advanced statistical modeling…

Student Achievement in Undergraduate Statistics: The Potential Value of Allowing Failure

ERIC Educational Resources Information Center

Ferrandino, Joseph A.

2016-01-01

This article details what resulted when I re-designed my undergraduate statistics course to allow failure as a learning strategy and focused on achievement rather than performance. A variety of within and between sample t-tests are utilized to determine the impact of unlimited test and quiz opportunities on student learning on both quizzes and…

Statistical significance of trace evidence matches using independent physicochemical measurements

NASA Astrophysics Data System (ADS)

Almirall, Jose R.; Cole, Michael; Furton, Kenneth G.; Gettinby, George

1997-02-01

A statistical approach to the significance of glass evidence is proposed using independent physicochemical measurements and chemometrics. Traditional interpretation of the significance of trace evidence matches or exclusions relies on qualitative descriptors such as 'indistinguishable from,' 'consistent with,' 'similar to' etc. By performing physical and chemical measurements with are independent of one another, the significance of object exclusions or matches can be evaluated statistically. One of the problems with this approach is that the human brain is excellent at recognizing and classifying patterns and shapes but performs less well when that object is represented by a numerical list of attributes. Chemometrics can be employed to group similar objects using clustering algorithms and provide statistical significance in a quantitative manner. This approach is enhanced when population databases exist or can be created and the data in question can be evaluated given these databases. Since the selection of the variables used and their pre-processing can greatly influence the outcome, several different methods could be employed in order to obtain a more complete picture of the information contained in the data. Presently, we report on the analysis of glass samples using refractive index measurements and the quantitative analysis of the concentrations of the metals: Mg, Al, Ca, Fe, Mn, Ba, Sr, Ti and Zr. The extension of this general approach to fiber and paint comparisons also is discussed. This statistical approach should not replace the current interpretative approaches to trace evidence matches or exclusions but rather yields an additional quantitative measure. The lack of sufficient general population databases containing the needed physicochemical measurements and the potential for confusion arising from statistical analysis currently hamper this approach and ways of overcoming these obstacles are presented.

Estimation of the geochemical threshold and its statistical significance

USGS Publications Warehouse

Miesch, A.T.

1981-01-01

A statistic is proposed for estimating the geochemical threshold and its statistical significance, or it may be used to identify a group of extreme values that can be tested for significance by other means. The statistic is the maximum gap between adjacent values in an ordered array after each gap has been adjusted for the expected frequency. The values in the ordered array are geochemical values transformed by either ln(?? - ??) or ln(?? - ??) and then standardized so that the mean is zero and the variance is unity. The expected frequency is taken from a fitted normal curve with unit area. The midpoint of an adjusted gap that exceeds the corresponding critical value may be taken as an estimate of the geochemical threshold, and the associated probability indicates the likelihood that the threshold separates two geochemical populations. The adjusted gap test may fail to identify threshold values if the variation tends to be continuous from background values to the higher values that reflect mineralized ground. However, the test will serve to identify other anomalies that may be too subtle to have been noted by other means. ?? 1981.

Decadal power in land air temperatures: Is it statistically significant?

NASA Astrophysics Data System (ADS)

Thejll, Peter A.

2001-12-01

The geographical distribution and properties of the well-known 10-11 year signal in terrestrial temperature records is investigated. By analyzing the Global Historical Climate Network data for surface air temperatures we verify that the signal is strongest in North America and is similar in nature to that reported earlier by R. G. Currie. The decadal signal is statistically significant for individual stations, but it is not possible to show that the signal is statistically significant globally, using strict tests. In North America, during the twentieth century, the decadal variability in the solar activity cycle is associated with the decadal part of the North Atlantic Oscillation index series in such a way that both of these signals correspond to the same spatial pattern of cooling and warming. A method for testing statistical results with Monte Carlo trials on data fields with specified temporal structure and specific spatial correlation retained is presented.

Statistical Significance for Hierarchical Clustering

PubMed Central

Kimes, Patrick K.; Liu, Yufeng; Hayes, D. Neil; Marron, J. S.

2017-01-01

Summary Cluster analysis has proved to be an invaluable tool for the exploratory and unsupervised analysis of high dimensional datasets. Among methods for clustering, hierarchical approaches have enjoyed substantial popularity in genomics and other fields for their ability to simultaneously uncover multiple layers of clustering structure. A critical and challenging question in cluster analysis is whether the identified clusters represent important underlying structure or are artifacts of natural sampling variation. Few approaches have been proposed for addressing this problem in the context of hierarchical clustering, for which the problem is further complicated by the natural tree structure of the partition, and the multiplicity of tests required to parse the layers of nested clusters. In this paper, we propose a Monte Carlo based approach for testing statistical significance in hierarchical clustering which addresses these issues. The approach is implemented as a sequential testing procedure guaranteeing control of the family-wise error rate. Theoretical justification is provided for our approach, and its power to detect true clustering structure is illustrated through several simulation studies and applications to two cancer gene expression datasets. PMID:28099990

A Comparison of the Achievement of Statistics Students Enrolled in Online and Face-to-Face Settings

ERIC Educational Resources Information Center

Christmann, Edwin P.

2017-01-01

This study compared the achievement of male and female students who were enrolled in an online univariate statistics course to students enrolled in a traditional face-to-face univariate statistics course. The subjects, 47 graduate students enrolled in univariate statistics classes at a public, comprehensive university, were randomly assigned to…

Detecting Statistically Significant Communities of Triangle Motifs in Undirected Networks

DTIC Science & Technology

2016-04-26

REPORT TYPE Final 3. DATES COVERED (From - To) 15 Oct 2014 to 14 Jan 2015 4. TITLE AND SUBTITLE Detecting statistically significant clusters of...extend the work of Perry et al. [6] by developing a statistical framework that supports the detection of triangle motif-based clusters in complex...priori, the need for triangle motif-based clustering . 2. Developed an algorithm for clustering undirected networks, where the triangle con guration was

Sibling Competition & Growth Tradeoffs. Biological vs. Statistical Significance.

PubMed

Kramer, Karen L; Veile, Amanda; Otárola-Castillo, Erik

2016-01-01

Early childhood growth has many downstream effects on future health and reproduction and is an important measure of offspring quality. While a tradeoff between family size and child growth outcomes is theoretically predicted in high-fertility societies, empirical evidence is mixed. This is often attributed to phenotypic variation in parental condition. However, inconsistent study results may also arise because family size confounds the potentially differential effects that older and younger siblings can have on young children's growth. Additionally, inconsistent results might reflect that the biological significance associated with different growth trajectories is poorly understood. This paper addresses these concerns by tracking children's monthly gains in height and weight from weaning to age five in a high fertility Maya community. We predict that: 1) as an aggregate measure family size will not have a major impact on child growth during the post weaning period; 2) competition from young siblings will negatively impact child growth during the post weaning period; 3) however because of their economic value, older siblings will have a negligible effect on young children's growth. Accounting for parental condition, we use linear mixed models to evaluate the effects that family size, younger and older siblings have on children's growth. Congruent with our expectations, it is younger siblings who have the most detrimental effect on children's growth. While we find statistical evidence of a quantity/quality tradeoff effect, the biological significance of these results is negligible in early childhood. Our findings help to resolve why quantity/quality studies have had inconsistent results by showing that sibling competition varies with sibling age composition, not just family size, and that biological significance is distinct from statistical significance.

Your Chi-Square Test Is Statistically Significant: Now What?

ERIC Educational Resources Information Center

Sharpe, Donald

2015-01-01

Applied researchers have employed chi-square tests for more than one hundred years. This paper addresses the question of how one should follow a statistically significant chi-square test result in order to determine the source of that result. Four approaches were evaluated: calculating residuals, comparing cells, ransacking, and partitioning. Data…

Statistical Significance Testing in Second Language Research: Basic Problems and Suggestions for Reform

ERIC Educational Resources Information Center

Norris, John M.

2015-01-01

Traditions of statistical significance testing in second language (L2) quantitative research are strongly entrenched in how researchers design studies, select analyses, and interpret results. However, statistical significance tests using "p" values are commonly misinterpreted by researchers, reviewers, readers, and others, leading to…

Sibling Competition & Growth Tradeoffs. Biological vs. Statistical Significance

PubMed Central

Kramer, Karen L.; Veile, Amanda; Otárola-Castillo, Erik

2016-01-01

Early childhood growth has many downstream effects on future health and reproduction and is an important measure of offspring quality. While a tradeoff between family size and child growth outcomes is theoretically predicted in high-fertility societies, empirical evidence is mixed. This is often attributed to phenotypic variation in parental condition. However, inconsistent study results may also arise because family size confounds the potentially differential effects that older and younger siblings can have on young children’s growth. Additionally, inconsistent results might reflect that the biological significance associated with different growth trajectories is poorly understood. This paper addresses these concerns by tracking children’s monthly gains in height and weight from weaning to age five in a high fertility Maya community. We predict that: 1) as an aggregate measure family size will not have a major impact on child growth during the post weaning period; 2) competition from young siblings will negatively impact child growth during the post weaning period; 3) however because of their economic value, older siblings will have a negligible effect on young children’s growth. Accounting for parental condition, we use linear mixed models to evaluate the effects that family size, younger and older siblings have on children’s growth. Congruent with our expectations, it is younger siblings who have the most detrimental effect on children’s growth. While we find statistical evidence of a quantity/quality tradeoff effect, the biological significance of these results is negligible in early childhood. Our findings help to resolve why quantity/quality studies have had inconsistent results by showing that sibling competition varies with sibling age composition, not just family size, and that biological significance is distinct from statistical significance. PMID:26938742

Quantification and statistical significance analysis of group separation in NMR-based metabonomics studies

PubMed Central

Goodpaster, Aaron M.; Kennedy, Michael A.

2015-01-01

Currently, no standard metrics are used to quantify cluster separation in PCA or PLS-DA scores plots for metabonomics studies or to determine if cluster separation is statistically significant. Lack of such measures makes it virtually impossible to compare independent or inter-laboratory studies and can lead to confusion in the metabonomics literature when authors putatively identify metabolites distinguishing classes of samples based on visual and qualitative inspection of scores plots that exhibit marginal separation. While previous papers have addressed quantification of cluster separation in PCA scores plots, none have advocated routine use of a quantitative measure of separation that is supported by a standard and rigorous assessment of whether or not the cluster separation is statistically significant. Here quantification and statistical significance of separation of group centroids in PCA and PLS-DA scores plots are considered. The Mahalanobis distance is used to quantify the distance between group centroids, and the two-sample Hotelling's T2 test is computed for the data, related to an F-statistic, and then an F-test is applied to determine if the cluster separation is statistically significant. We demonstrate the value of this approach using four datasets containing various degrees of separation, ranging from groups that had no apparent visual cluster separation to groups that had no visual cluster overlap. Widespread adoption of such concrete metrics to quantify and evaluate the statistical significance of PCA and PLS-DA cluster separation would help standardize reporting of metabonomics data. PMID:26246647

A Mediation Model to Explain the Role of Mathematics Skills and Probabilistic Reasoning on Statistics Achievement

ERIC Educational Resources Information Center

Primi, Caterina; Donati, Maria Anna; Chiesi, Francesca

2016-01-01

Among the wide range of factors related to the acquisition of statistical knowledge, competence in basic mathematics, including basic probability, has received much attention. In this study, a mediation model was estimated to derive the total, direct, and indirect effects of mathematical competence on statistics achievement taking into account…

Relationship between academic motivation and mathematics achievement among Indian adolescents in Canada and India.

PubMed

Areepattamannil, Shaljan

2014-01-01

This study examined the relationships between academic motivation-intrinsic motivation, extrinsic motivation, amotivation-and mathematics achievement among 363 Indian adolescents in India and 355 Indian immigrant adolescents in Canada. Results of hierarchical multiple regression analyses showed that intrinsic motivation, extrinsic motivation, and amotivation were not statistically significantly related to mathematics achievement among Indian adolescents in India. In contrast, both intrinsic motivation and extrinsic motivation were statistically significantly related to mathematics achievement among Indian immigrant adolescents in Canada. While intrinsic motivation was a statistically significant positive predictor of mathematics achievement among Indian immigrant adolescents in Canada, extrinsic motivation was a statistically significant negative predictor of mathematics achievement among Indian immigrant adolescents in Canada. Amotivation was not statistically significantly related to mathematics achievement among Indian immigrant adolescents in Canada. Implications of the findings for pedagogy and practice are discussed.

Social significance of community structure: Statistical view

NASA Astrophysics Data System (ADS)

Li, Hui-Jia; Daniels, Jasmine J.

2015-01-01

Community structure analysis is a powerful tool for social networks that can simplify their topological and functional analysis considerably. However, since community detection methods have random factors and real social networks obtained from complex systems always contain error edges, evaluating the significance of a partitioned community structure is an urgent and important question. In this paper, integrating the specific characteristics of real society, we present a framework to analyze the significance of a social community. The dynamics of social interactions are modeled by identifying social leaders and corresponding hierarchical structures. Instead of a direct comparison with the average outcome of a random model, we compute the similarity of a given node with the leader by the number of common neighbors. To determine the membership vector, an efficient community detection algorithm is proposed based on the position of the nodes and their corresponding leaders. Then, using a log-likelihood score, the tightness of the community can be derived. Based on the distribution of community tightness, we establish a connection between p -value theory and network analysis, and then we obtain a significance measure of statistical form . Finally, the framework is applied to both benchmark networks and real social networks. Experimental results show that our work can be used in many fields, such as determining the optimal number of communities, analyzing the social significance of a given community, comparing the performance among various algorithms, etc.

Statistical significance versus clinical relevance.

PubMed

van Rijn, Marieke H C; Bech, Anneke; Bouyer, Jean; van den Brand, Jan A J G

2017-04-01

In March this year, the American Statistical Association (ASA) posted a statement on the correct use of P-values, in response to a growing concern that the P-value is commonly misused and misinterpreted. We aim to translate these warnings given by the ASA into a language more easily understood by clinicians and researchers without a deep background in statistics. Moreover, we intend to illustrate the limitations of P-values, even when used and interpreted correctly, and bring more attention to the clinical relevance of study findings using two recently reported studies as examples. We argue that P-values are often misinterpreted. A common mistake is saying that P < 0.05 means that the null hypothesis is false, and P ≥0.05 means that the null hypothesis is true. The correct interpretation of a P-value of 0.05 is that if the null hypothesis were indeed true, a similar or more extreme result would occur 5% of the times upon repeating the study in a similar sample. In other words, the P-value informs about the likelihood of the data given the null hypothesis and not the other way around. A possible alternative related to the P-value is the confidence interval (CI). It provides more information on the magnitude of an effect and the imprecision with which that effect was estimated. However, there is no magic bullet to replace P-values and stop erroneous interpretation of scientific results. Scientists and readers alike should make themselves familiar with the correct, nuanced interpretation of statistical tests, P-values and CIs. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Students' Achievements in a Statistics Course in Relation to Motivational Aspects and Study Behaviour

ERIC Educational Resources Information Center

Bude, Luc; Van De Wiel, Margaretha W. J.; Imbos, Tjaart; Candel, Math J. J. M.; Broers, Nick J.; Berger, Martijn P. F.

2007-01-01

The present study focuses on motivational constructs and their effect on students' academic achievement within an existing statistics course. First-year Health Sciences students completed a questionnaire that measures several motivational constructs: dimensions of causal attributions, outcome expectancy, affect, and study behaviour, all with…

Statistical Significance and Effect Size: Two Sides of a Coin.

ERIC Educational Resources Information Center

Fan, Xitao

This paper suggests that statistical significance testing and effect size are two sides of the same coin; they complement each other, but do not substitute for one another. Good research practice requires that both should be taken into consideration to make sound quantitative decisions. A Monte Carlo simulation experiment was conducted, and a…

Publication of statistically significant research findings in prosthodontics & implant dentistry in the context of other dental specialties.

PubMed

Papageorgiou, Spyridon N; Kloukos, Dimitrios; Petridis, Haralampos; Pandis, Nikolaos

2015-10-01

To assess the hypothesis that there is excessive reporting of statistically significant studies published in prosthodontic and implantology journals, which could indicate selective publication. The last 30 issues of 9 journals in prosthodontics and implant dentistry were hand-searched for articles with statistical analyses. The percentages of significant and non-significant results were tabulated by parameter of interest. Univariable/multivariable logistic regression analyses were applied to identify possible predictors of reporting statistically significance findings. The results of this study were compared with similar studies in dentistry with random-effects meta-analyses. From the 2323 included studies 71% of them reported statistically significant results, with the significant results ranging from 47% to 86%. Multivariable modeling identified that geographical area and involvement of statistician were predictors of statistically significant results. Compared to interventional studies, the odds that in vitro and observational studies would report statistically significant results was increased by 1.20 times (OR: 2.20, 95% CI: 1.66-2.92) and 0.35 times (OR: 1.35, 95% CI: 1.05-1.73), respectively. The probability of statistically significant results from randomized controlled trials was significantly lower compared to various study designs (difference: 30%, 95% CI: 11-49%). Likewise the probability of statistically significant results in prosthodontics and implant dentistry was lower compared to other dental specialties, but this result did not reach statistical significant (P>0.05). The majority of studies identified in the fields of prosthodontics and implant dentistry presented statistically significant results. The same trend existed in publications of other specialties in dentistry. Copyright © 2015 Elsevier Ltd. All rights reserved.

"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…

Statistical significance of the rich-club phenomenon in complex networks

NASA Astrophysics Data System (ADS)

Jiang, Zhi-Qiang; Zhou, Wei-Xing

2008-04-01

We propose that the rich-club phenomenon in complex networks should be defined in the spirit of bootstrapping, in which a null model is adopted to assess the statistical significance of the rich-club detected. Our method can serve as a definition of the rich-club phenomenon and is applied to analyze three real networks and three model networks. The results show significant improvement compared with previously reported results. We report a dilemma with an exceptional example, showing that there does not exist an omnipotent definition for the rich-club phenomenon.

Fostering Students' Statistical Literacy through Significant Learning Experience

ERIC Educational Resources Information Center

Krishnan, Saras

2015-01-01

A major objective of statistics education is to develop students' statistical literacy that enables them to be educated users of data in context. Teaching statistics in today's educational settings is not an easy feat because teachers have a huge task in keeping up with the demands of the new generation of learners. The present day students have…

Distinguishing between statistical significance and practical/clinical meaningfulness using statistical inference.

PubMed

Wilkinson, Michael

2014-03-01

Decisions about support for predictions of theories in light of data are made using statistical inference. The dominant approach in sport and exercise science is the Neyman-Pearson (N-P) significance-testing approach. When applied correctly it provides a reliable procedure for making dichotomous decisions for accepting or rejecting zero-effect null hypotheses with known and controlled long-run error rates. Type I and type II error rates must be specified in advance and the latter controlled by conducting an a priori sample size calculation. The N-P approach does not provide the probability of hypotheses or indicate the strength of support for hypotheses in light of data, yet many scientists believe it does. Outcomes of analyses allow conclusions only about the existence of non-zero effects, and provide no information about the likely size of true effects or their practical/clinical value. Bayesian inference can show how much support data provide for different hypotheses, and how personal convictions should be altered in light of data, but the approach is complicated by formulating probability distributions about prior subjective estimates of population effects. A pragmatic solution is magnitude-based inference, which allows scientists to estimate the true magnitude of population effects and how likely they are to exceed an effect magnitude of practical/clinical importance, thereby integrating elements of subjective Bayesian-style thinking. While this approach is gaining acceptance, progress might be hastened if scientists appreciate the shortcomings of traditional N-P null hypothesis significance testing.

Statistics Refresher for Molecular Imaging Technologists, Part 2: Accuracy of Interpretation, Significance, and Variance.

PubMed

Farrell, Mary Beth

2018-06-01

This article is the second part of a continuing education series reviewing basic statistics that nuclear medicine and molecular imaging technologists should understand. In this article, the statistics for evaluating interpretation accuracy, significance, and variance are discussed. Throughout the article, actual statistics are pulled from the published literature. We begin by explaining 2 methods for quantifying interpretive accuracy: interreader and intrareader reliability. Agreement among readers can be expressed simply as a percentage. However, the Cohen κ-statistic is a more robust measure of agreement that accounts for chance. The higher the κ-statistic is, the higher is the agreement between readers. When 3 or more readers are being compared, the Fleiss κ-statistic is used. Significance testing determines whether the difference between 2 conditions or interventions is meaningful. Statistical significance is usually expressed using a number called a probability ( P ) value. Calculation of P value is beyond the scope of this review. However, knowing how to interpret P values is important for understanding the scientific literature. Generally, a P value of less than 0.05 is considered significant and indicates that the results of the experiment are due to more than just chance. Variance, standard deviation (SD), confidence interval, and standard error (SE) explain the dispersion of data around a mean of a sample drawn from a population. SD is commonly reported in the literature. A small SD indicates that there is not much variation in the sample data. Many biologic measurements fall into what is referred to as a normal distribution taking the shape of a bell curve. In a normal distribution, 68% of the data will fall within 1 SD, 95% will fall within 2 SDs, and 99.7% will fall within 3 SDs. Confidence interval defines the range of possible values within which the population parameter is likely to lie and gives an idea of the precision of the statistic being

Using the Bootstrap Method for a Statistical Significance Test of Differences between Summary Histograms

NASA Technical Reports Server (NTRS)

Xu, Kuan-Man

2006-01-01

A new method is proposed to compare statistical differences between summary histograms, which are the histograms summed over a large ensemble of individual histograms. It consists of choosing a distance statistic for measuring the difference between summary histograms and using a bootstrap procedure to calculate the statistical significance level. Bootstrapping is an approach to statistical inference that makes few assumptions about the underlying probability distribution that describes the data. Three distance statistics are compared in this study. They are the Euclidean distance, the Jeffries-Matusita distance and the Kuiper distance. The data used in testing the bootstrap method are satellite measurements of cloud systems called cloud objects. Each cloud object is defined as a contiguous region/patch composed of individual footprints or fields of view. A histogram of measured values over footprints is generated for each parameter of each cloud object and then summary histograms are accumulated over all individual histograms in a given cloud-object size category. The results of statistical hypothesis tests using all three distances as test statistics are generally similar, indicating the validity of the proposed method. The Euclidean distance is determined to be most suitable after comparing the statistical tests of several parameters with distinct probability distributions among three cloud-object size categories. Impacts on the statistical significance levels resulting from differences in the total lengths of satellite footprint data between two size categories are also discussed.

Using the Expectancy Value Model of Motivation to Understand the Relationship between Student Attitudes and Achievement in Statistics

ERIC Educational Resources Information Center

Hood, Michelle; Creed, Peter A.; Neumann, David L.

2012-01-01

We tested a model of the relationship between attitudes toward statistics and achievement based on Eccles' Expectancy Value Model (1983). Participants (n = 149; 83% female) were second-year Australian university students in a psychology statistics course (mean age = 23.36 years, SD = 7.94 years). We obtained demographic details, past performance,…

SOARing Into Strategic Planning: Engaging Nurses to Achieve Significant Outcomes.

PubMed

Wadsworth, Barbara; Felton, Fiona; Linus, Rita

2016-01-01

In 2013, a new system chief nursing officer engaged the nursing leaders and staff in an Appreciative Inquiry process utilizing strengths, opportunities, aspirations, and results (SOAR), and a Journey of Excellence to assess and understand the current environment. The ultimate goal was to engage all nurses in strategic planning and goal setting to connect their patient care to the system strategic initiatives. This work led to the creation of a nursing vision, a revised professional practice model and greater council alignment, resulting in significant positive change and ongoing advancement throughout the system. The shared decision-making structure was key to the process with a direct connection of each council's goals, leading to the successful achievement of 34 of the 36 goals in 2 years. This article outlines the process, tools, and staff engagement strategies used to achieve system-wide success. This methodology has improved the outcomes across the organization in both small and system-wide work groups. This work can easily be replicated and adapted to help disparate staffs brought together through mergers or acquisitions to become aligned as a new team. This process, model, and framework, provides structure and results in significant outcomes that recognizes and celebrates the work of individual entities while aligning future strategies and goals.

Strategies for Testing Statistical and Practical Significance in Detecting DIF with Logistic Regression Models

ERIC Educational Resources Information Center

Fidalgo, Angel M.; Alavi, Seyed Mohammad; Amirian, Seyed Mohammad Reza

2014-01-01

This study examines three controversial aspects in differential item functioning (DIF) detection by logistic regression (LR) models: first, the relative effectiveness of different analytical strategies for detecting DIF; second, the suitability of the Wald statistic for determining the statistical significance of the parameters of interest; and…

Clinical relevance vs. statistical significance: Using neck outcomes in patients with temporomandibular disorders as an example.

PubMed

Armijo-Olivo, Susan; Warren, Sharon; Fuentes, Jorge; Magee, David J

2011-12-01

Statistical significance has been used extensively to evaluate the results of research studies. Nevertheless, it offers only limited information to clinicians. The assessment of clinical relevance can facilitate the interpretation of the research results into clinical practice. The objective of this study was to explore different methods to evaluate the clinical relevance of the results using a cross-sectional study as an example comparing different neck outcomes between subjects with temporomandibular disorders and healthy controls. Subjects were compared for head and cervical posture, maximal cervical muscle strength, endurance of the cervical flexor and extensor muscles, and electromyographic activity of the cervical flexor muscles during the CranioCervical Flexion Test (CCFT). The evaluation of clinical relevance of the results was performed based on the effect size (ES), minimal important difference (MID), and clinical judgement. The results of this study show that it is possible to have statistical significance without having clinical relevance, to have both statistical significance and clinical relevance, to have clinical relevance without having statistical significance, or to have neither statistical significance nor clinical relevance. The evaluation of clinical relevance in clinical research is crucial to simplify the transfer of knowledge from research into practice. Clinical researchers should present the clinical relevance of their results. Copyright © 2011 Elsevier Ltd. All rights reserved.

Visual-Motor Test Performance: Race and Achievement Variables.

ERIC Educational Resources Information Center

Fuller, Gerald B.; Friedrich, Douglas

1979-01-01

Rural Black and White children of variant academic achievement were tested on the Minnesota Percepto-Diagnostic Test, which consists of six gestalt designs for the subject to copy. Analyses resulted only in a significant achievement effect; when intellectual level was statistically controlled, race was not a significant variable. (Editor/SJL)

Structural Model of the Effects of Cognitive and Affective Factors on the Achievement of Arabic-Speaking Pre-Service Teachers in Introductory Statistics

ERIC Educational Resources Information Center

Nasser, Fadia M.

2004-01-01

This study examined the extent to which statistics and mathematics anxiety, attitudes toward mathematics and statistics, motivation and mathematical aptitude can explain the achievement of Arabic speaking pre-service teachers in introductory statistics. Complete data were collected from 162 pre-service teachers enrolled in an academic…

Learning Model and Form of Assesment toward the Inferensial Statistical Achievement by Controlling Numeric Thinking Skills

ERIC Educational Resources Information Center

Widiana, I. Wayan; Jampel, I. Nyoman

2016-01-01

This study aimed to find out the effect of learning model and form of assessment toward inferential statistical achievement after controlling numeric thinking skills. This study was quasi experimental study with 130 students as the sample. The data analysis used ANCOVA. After controlling numeric thinking skills, the result of this study show that:…

The fragility of statistically significant findings from randomized trials in head and neck surgery.

PubMed

Noel, Christopher W; McMullen, Caitlin; Yao, Christopher; Monteiro, Eric; Goldstein, David P; Eskander, Antoine; de Almeida, John R

2018-04-23

The Fragility Index (FI) is a novel tool for evaluating the robustness of statistically significant findings in a randomized control trial (RCT). It measures the number of events upon which statistical significance depends. We sought to calculate the FI scores for RCTs in the head and neck cancer literature where surgery was a primary intervention. Potential articles were identified in PubMed (MEDLINE), Embase, and Cochrane without publication date restrictions. Two reviewers independently screened eligible RCTs reporting at least one dichotomous and statistically significant outcome. The data from each trial were extracted and the FI scores were calculated. Associations between trial characteristics and FI were determined. In total, 27 articles were identified. The median sample size was 67.5 (interquartile range [IQR] = 42-143) and the median number of events per trial was 8 (IQR = 2.25-18.25). The median FI score was 1 (IQR = 0-2.5), meaning that changing one patient from a nonevent to an event in the treatment arm would change the result to a statistically nonsignificant result, or P > .05. The FI score was less than the number of patients lost to follow-up in 71% of cases. The FI score was found to be moderately correlated with P value (ρ = -0.52, P = .007) and with journal impact factor (ρ = 0.49, P = .009) on univariable analysis. On multivariable analysis, only the P value was found to be a predictor of FI score (P = .001). Randomized trials in the head and neck cancer literature where surgery is a primary modality are relatively nonrobust statistically with low FI scores. Laryngoscope, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

Identification of Microorganisms by High Resolution Tandem Mass Spectrometry with Accurate Statistical Significance

NASA Astrophysics Data System (ADS)

Alves, Gelio; Wang, Guanghui; Ogurtsov, Aleksey Y.; Drake, Steven K.; Gucek, Marjan; Suffredini, Anthony F.; Sacks, David B.; Yu, Yi-Kuo

2016-02-01

Correct and rapid identification of microorganisms is the key to the success of many important applications in health and safety, including, but not limited to, infection treatment, food safety, and biodefense. With the advance of mass spectrometry (MS) technology, the speed of identification can be greatly improved. However, the increasing number of microbes sequenced is challenging correct microbial identification because of the large number of choices present. To properly disentangle candidate microbes, one needs to go beyond apparent morphology or simple `fingerprinting'; to correctly prioritize the candidate microbes, one needs to have accurate statistical significance in microbial identification. We meet these challenges by using peptidome profiles of microbes to better separate them and by designing an analysis method that yields accurate statistical significance. Here, we present an analysis pipeline that uses tandem MS (MS/MS) spectra for microbial identification or classification. We have demonstrated, using MS/MS data of 81 samples, each composed of a single known microorganism, that the proposed pipeline can correctly identify microorganisms at least at the genus and species levels. We have also shown that the proposed pipeline computes accurate statistical significances, i.e., E-values for identified peptides and unified E-values for identified microorganisms. The proposed analysis pipeline has been implemented in MiCId, a freely available software for Microorganism Classification and Identification. MiCId is available for download at http://www.ncbi.nlm.nih.gov/CBBresearch/Yu/downloads.html.

A Meta-Analytic Review of Studies of the Effectiveness of Small-Group Learning Methods on Statistics Achievement

ERIC Educational Resources Information Center

Kalaian, Sema A.; Kasim, Rafa M.

2014-01-01

This meta-analytic study focused on the quantitative integration and synthesis of the accumulated pedagogical research in undergraduate statistics education literature. These accumulated research studies compared the academic achievement of students who had been instructed using one of the various forms of small-group learning methods to those who…

Reporting of statistically significant results at ClinicalTrials.gov for completed superiority randomized controlled trials.

PubMed

Dechartres, Agnes; Bond, Elizabeth G; Scheer, Jordan; Riveros, Carolina; Atal, Ignacio; Ravaud, Philippe

2016-11-30

Publication bias and other reporting bias have been well documented for journal articles, but no study has evaluated the nature of results posted at ClinicalTrials.gov. We aimed to assess how many randomized controlled trials (RCTs) with results posted at ClinicalTrials.gov report statistically significant results and whether the proportion of trials with significant results differs when no treatment effect estimate or p-value is posted. We searched ClinicalTrials.gov in June 2015 for all studies with results posted. We included completed RCTs with a superiority hypothesis and considered results for the first primary outcome with results posted. For each trial, we assessed whether a treatment effect estimate and/or p-value was reported at ClinicalTrials.gov and if yes, whether results were statistically significant. If no treatment effect estimate or p-value was reported, we calculated the treatment effect and corresponding p-value using results per arm posted at ClinicalTrials.gov when sufficient data were reported. From the 17,536 studies with results posted at ClinicalTrials.gov, we identified 2823 completed phase 3 or 4 randomized trials with a superiority hypothesis. Of these, 1400 (50%) reported a treatment effect estimate and/or p-value. Results were statistically significant for 844 trials (60%), with a median p-value of 0.01 (Q1-Q3: 0.001-0.26). For the 1423 trials with no treatment effect estimate or p-value posted, we could calculate the treatment effect and corresponding p-value using results reported per arm for 929 (65%). For 494 trials (35%), p-values could not be calculated mainly because of insufficient reporting, censored data, or repeated measurements over time. For the 929 trials we could calculate p-values, we found statistically significant results for 342 (37%), with a median p-value of 0.19 (Q1-Q3: 0.005-0.59). Half of the trials with results posted at ClinicalTrials.gov reported a treatment effect estimate and/or p-value, with significant

Relationship between affect and achievement in science and mathematics in Malaysia and Singapore

NASA Astrophysics Data System (ADS)

Thoe Ng, Khar; Fah Lay, Yoon; Areepattamannil, Shaljan; Treagust, David F.; Chandrasegaran, A. L.

2012-11-01

Background : The Trends in International Mathematics and Science Study (TIMSS) assesses the quality of the teaching and learning of science and mathematics among Grades 4 and 8 students across participating countries. Purpose : This study explored the relationship between positive affect towards science and mathematics and achievement in science and mathematics among Malaysian and Singaporean Grade 8 students. Sample : In total, 4466 Malaysia students and 4599 Singaporean students from Grade 8 who participated in TIMSS 2007 were involved in this study. Design and method : Students' achievement scores on eight items in the survey instrument that were reported in TIMSS 2007 were used as the dependent variable in the analysis. Students' scores on four items in the TIMSS 2007 survey instrument pertaining to students' affect towards science and mathematics together with students' gender, language spoken at home and parental education were used as the independent variables. Results : Positive affect towards science and mathematics indicated statistically significant predictive effects on achievement in the two subjects for both Malaysian and Singaporean Grade 8 students. There were statistically significant predictive effects on mathematics achievement for the students' gender, language spoken at home and parental education for both Malaysian and Singaporean students, with R 2 = 0.18 and 0.21, respectively. However, only parental education showed statistically significant predictive effects on science achievement for both countries. For Singapore, language spoken at home also demonstrated statistically significant predictive effects on science achievement, whereas gender did not. For Malaysia, neither gender nor language spoken at home had statistically significant predictive effects on science achievement. Conclusions : It is important for educators to consider implementing self-concept enhancement intervention programmes by incorporating 'affect' components of academic

Statistical significance of task related deep brain EEG dynamic changes in the time-frequency domain.

PubMed

Chládek, J; Brázdil, M; Halámek, J; Plešinger, F; Jurák, P

2013-01-01

We present an off-line analysis procedure for exploring brain activity recorded from intra-cerebral electroencephalographic data (SEEG). The objective is to determine the statistical differences between different types of stimulations in the time-frequency domain. The procedure is based on computing relative signal power change and subsequent statistical analysis. An example of characteristic statistically significant event-related de/synchronization (ERD/ERS) detected across different frequency bands following different oddball stimuli is presented. The method is used for off-line functional classification of different brain areas.

Intensive inpatient treatment for bulimia nervosa: Statistical and clinical significance of symptom changes.

PubMed

Diedrich, Alice; Schlegl, Sandra; Greetfeld, Martin; Fumi, Markus; Voderholzer, Ulrich

2018-03-01

This study examines the statistical and clinical significance of symptom changes during an intensive inpatient treatment program with a strong psychotherapeutic focus for individuals with severe bulimia nervosa. 295 consecutively admitted bulimic patients were administered the Structured Interview for Anorexic and Bulimic Syndromes-Self-Rating (SIAB-S), the Eating Disorder Inventory-2 (EDI-2), the Brief Symptom Inventory (BSI), and the Beck Depression Inventory-II (BDI-II) at treatment intake and discharge. Results indicated statistically significant symptom reductions with large effect sizes regarding severity of binge eating and compensatory behavior (SIAB-S), overall eating disorder symptom severity (EDI-2), overall psychopathology (BSI), and depressive symptom severity (BDI-II) even when controlling for antidepressant medication. The majority of patients showed either reliable (EDI-2: 33.7%, BSI: 34.8%, BDI-II: 18.1%) or even clinically significant symptom changes (EDI-2: 43.2%, BSI: 33.9%, BDI-II: 56.9%). Patients with clinically significant improvement were less distressed at intake and less likely to suffer from a comorbid borderline personality disorder when compared with those who did not improve to a clinically significant extent. Findings indicate that intensive psychotherapeutic inpatient treatment may be effective in about 75% of severely affected bulimic patients. For the remaining non-responding patients, inpatient treatment might be improved through an even stronger focus on the reduction of comorbid borderline personality traits.

SU-F-BRD-05: Dosimetric Comparison of Protocol-Based SBRT Lung Treatment Modalities: Statistically Significant VMAT Advantages Over Fixed- Beam IMRT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Best, R; Harrell, A; Geesey, C

2014-06-15

Purpose: The purpose of this study is to inter-compare and find statistically significant differences between flattened field fixed-beam (FB) IMRT with flattening-filter free (FFF) volumetric modulated arc therapy (VMAT) for stereotactic body radiation therapy SBRT. Methods: SBRT plans using FB IMRT and FFF VMAT were generated for fifteen SBRT lung patients using 6 MV beams. For each patient, both IMRT and VMAT plans were created for comparison. Plans were generated utilizing RTOG 0915 (peripheral, 10 patients) and RTOG 0813 (medial, 5 patients) lung protocols. Target dose, critical structure dose, and treatment time were compared and tested for statistical significance. Parametersmore » of interest included prescription isodose surface coverage, target dose heterogeneity, high dose spillage (location and volume), low dose spillage (location and volume), lung dose spillage, and critical structure maximum- and volumetric-dose limits. Results: For all criteria, we found equivalent or higher conformality with VMAT plans as well as reduced critical structure doses. Several differences passed a Student's t-test of significance: VMAT reduced the high dose spillage, evaluated with conformality index (CI), by an average of 9.4%±15.1% (p=0.030) compared to IMRT. VMAT plans reduced the lung volume receiving 20 Gy by 16.2%±15.0% (p=0.016) compared with IMRT. For the RTOG 0915 peripheral lesions, the volumes of lung receiving 12.4 Gy and 11.6 Gy were reduced by 27.0%±13.8% and 27.5%±12.6% (for both, p<0.001) in VMAT plans. Of the 26 protocol pass/fail criteria, VMAT plans were able to achieve an average of 0.2±0.7 (p=0.026) more constraints than the IMRT plans. Conclusions: FFF VMAT has dosimetric advantages over fixed beam IMRT for lung SBRT. Significant advantages included increased dose conformity, and reduced organs-at-risk doses. The overall improvements in terms of protocol pass/fail criteria were more modest and will require more patient data to establish

Cloud-based solution to identify statistically significant MS peaks differentiating sample categories.

PubMed

Ji, Jun; Ling, Jeffrey; Jiang, Helen; Wen, Qiaojun; Whitin, John C; Tian, Lu; Cohen, Harvey J; Ling, Xuefeng B

2013-03-23

Mass spectrometry (MS) has evolved to become the primary high throughput tool for proteomics based biomarker discovery. Until now, multiple challenges in protein MS data analysis remain: large-scale and complex data set management; MS peak identification, indexing; and high dimensional peak differential analysis with the concurrent statistical tests based false discovery rate (FDR). "Turnkey" solutions are needed for biomarker investigations to rapidly process MS data sets to identify statistically significant peaks for subsequent validation. Here we present an efficient and effective solution, which provides experimental biologists easy access to "cloud" computing capabilities to analyze MS data. The web portal can be accessed at http://transmed.stanford.edu/ssa/. Presented web application supplies large scale MS data online uploading and analysis with a simple user interface. This bioinformatic tool will facilitate the discovery of the potential protein biomarkers using MS.

Sex differences in educational encouragement and academic achievement.

PubMed

Khan, Aqeel

2012-08-01

Sex differences in educational encouragement and their predictiveness of academic achievement were examined among 442 secondary school students (M age = 13.2 yr., SD = 1.9). Education-related encouragement received from mothers, fathers, friends, and teachers was assessed. Academic achievement was based on student self-reports and grades. Female adolescents reported receiving statistically significantly more educational encouragement from their mothers, fathers, friends, and teachers than did male adolescents. In regression, sex and educational encouragement from parents, friends, and teachers were found to be significant predictors of academic achievement.

Statistical Significance of Optical Map Alignments

PubMed Central

Sarkar, Deepayan; Goldstein, Steve; Schwartz, David C.

2012-01-01

Abstract The Optical Mapping System constructs ordered restriction maps spanning entire genomes through the assembly and analysis of large datasets comprising individually analyzed genomic DNA molecules. Such restriction maps uniquely reveal mammalian genome structure and variation, but also raise computational and statistical questions beyond those that have been solved in the analysis of smaller, microbial genomes. We address the problem of how to filter maps that align poorly to a reference genome. We obtain map-specific thresholds that control errors and improve iterative assembly. We also show how an optimal self-alignment score provides an accurate approximation to the probability of alignment, which is useful in applications seeking to identify structural genomic abnormalities. PMID:22506568

Power, effects, confidence, and significance: an investigation of statistical practices in nursing research.

PubMed

Gaskin, Cadeyrn J; Happell, Brenda

2014-05-01

improvement. Most importantly, researchers should abandon the misleading practice of interpreting the results from inferential tests based solely on whether they are statistically significant (or not) and, instead, focus on reporting and interpreting effect sizes, confidence intervals, and significance levels. Nursing researchers also need to conduct and report a priori power analyses, and to address the issue of Type I experiment-wise error inflation in their studies. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Explaining Math Achievement: Personality, Motivation, and Trust

ERIC Educational Resources Information Center

Kilic-Bebek, Ebru

2009-01-01

This study investigated the statistical significance of student trust next to the well-tested constructs of personality and motivation to determine whether trust is a significant predictor of course achievement in college math courses. Participants were 175 students who were taking undergraduate math courses in an urban public university. The…

Factors significantly related to science achievement of Malaysian middle school students: An analysis of TIMSS 1999 data

NASA Astrophysics Data System (ADS)

Mokshein, Siti Eshah

The importance of science and technology in the global economy has led to growing emphasis on math and science achievement all over the world. In this study, I seek to identify variables at the student-level and school-level that account for the variation in science achievement of the eighth graders in Malaysia. Using the Third International Math and Science Study (TIMSS) 1999 for Malaysia, a series of HLM analysis was performed. Results indicate that (1) variation in overall science achievement is greater between schools than within schools; (2) both the selected student-level and school-level factors are Important in explaining the variation in the eight graders' achievement In science; (3) the selected student-level variables explain about 13% of the variation in students' achievement within schools, but as an aggregate, they account for a much larger proportion of the between-school variance; (4) the selected school-level variables account for about 55% of the variation between schools; (5) within schools, the effects of self-concept In science, awareness of the social implications of science, gender, and home educational resources are significantly related to achievement; (6) the effects of self-concept in science and awareness of social implications of science are significant even after controlling for the effects of SES; (7) between schools, the effects of the mean of home educational resources, mean of parents' education, mean of awareness of the social implications of science, and emphasis on conducting experiments are significantly related to achievement; (8) the effects of SES variables explain about 50% of the variation in the school means achievement; and (9) the effects of emphasis on conducting experiments on achievement are significant even after controlling for the effects of SES. Since it is hard to change the society, it is recommended that efforts to Improve science achievement be focused more at the school-level, concentrating on variables that

Values, achievement goals, and individual-oriented and social-oriented achievement motivations among Chinese and Indonesian secondary school students.

PubMed

Liem, Arief Darmanegara; Nie, Youyan

2008-10-01

This study examined how values related to achievement goals and individual-oriented and social-oriented achievement motivations among secondary school students in China (N = 355) and Indonesia (N = 356). Statistical comparisons showed the Chinese students endorsed more strongly than the Indonesian students on self-direction and hedonism values, individual-oriented achievement motivation, and mastery-approach goals. Conversely, the Indonesian students endorsed more strongly than their Chinese counterparts on security, conformity, tradition, universalism and achievement values, social-oriented achievement motivation, and performance-approach and mastery-avoidance goals. Values explained a significant amount of the variance in almost all of the dimensions of motivation. Etic and emic relationships between values and achievement motivations were found.

The Achievement Impacts of Arkansas Open-Enrollment Charter Schools

ERIC Educational Resources Information Center

Mills, Jonathan N.

2013-01-01

This article examines the impacts of Arkansas charter schools on the academic achievement of participating students. Our findings are that charter schools have small but statistically significant, negative impacts on student achievements for both math and literacy. Such negative effects, however, tend to decline with the number of years of charter…

Ethnicity, Effort, Self-Efficacy, Worry, and Statistics Achievement in Malaysia: A Construct Validation of the State-Trait Motivation Model

ERIC Educational Resources Information Center

Awang-Hashim, Rosa; O'Neil, Harold F., Jr.; Hocevar, Dennis

2002-01-01

The relations between motivational constructs, effort, self-efficacy and worry, and statistics achievement were investigated in a sample of 360 undergraduates in Malaysia. Both trait (cross-situational) and state (task-specific) measures of each construct were used to test a mediational trait (r) state (r) performance (TSP) model. As hypothesized,…

Statistics of Statisticians: Critical Mass of Statistics and Operational Research Groups

NASA Astrophysics Data System (ADS)

Kenna, Ralph; Berche, Bertrand

Using a recently developed model, inspired by mean field theory in statistical physics, and data from the UK's Research Assessment Exercise, we analyse the relationship between the qualities of statistics and operational research groups and the quantities of researchers in them. Similar to other academic disciplines, we provide evidence for a linear dependency of quality on quantity up to an upper critical mass, which is interpreted as the average maximum number of colleagues with whom a researcher can communicate meaningfully within a research group. The model also predicts a lower critical mass, which research groups should strive to achieve to avoid extinction. For statistics and operational research, the lower critical mass is estimated to be 9 ± 3. The upper critical mass, beyond which research quality does not significantly depend on group size, is 17 ± 6.

How to get statistically significant effects in any ERP experiment (and why you shouldn't).

PubMed

Luck, Steven J; Gaspelin, Nicholas

2017-01-01

ERP experiments generate massive datasets, often containing thousands of values for each participant, even after averaging. The richness of these datasets can be very useful in testing sophisticated hypotheses, but this richness also creates many opportunities to obtain effects that are statistically significant but do not reflect true differences among groups or conditions (bogus effects). The purpose of this paper is to demonstrate how common and seemingly innocuous methods for quantifying and analyzing ERP effects can lead to very high rates of significant but bogus effects, with the likelihood of obtaining at least one such bogus effect exceeding 50% in many experiments. We focus on two specific problems: using the grand-averaged data to select the time windows and electrode sites for quantifying component amplitudes and latencies, and using one or more multifactor statistical analyses. Reanalyses of prior data and simulations of typical experimental designs are used to show how these problems can greatly increase the likelihood of significant but bogus results. Several strategies are described for avoiding these problems and for increasing the likelihood that significant effects actually reflect true differences among groups or conditions. © 2016 Society for Psychophysiological Research.

How to Get Statistically Significant Effects in Any ERP Experiment (and Why You Shouldn’t)

PubMed Central

Luck, Steven J.; Gaspelin, Nicholas

2016-01-01

Event-related potential (ERP) experiments generate massive data sets, often containing thousands of values for each participant, even after averaging. The richness of these data sets can be very useful in testing sophisticated hypotheses, but this richness also creates many opportunities to obtain effects that are statistically significant but do not reflect true differences among groups or conditions (bogus effects). The purpose of this paper is to demonstrate how common and seemingly innocuous methods for quantifying and analyzing ERP effects can lead to very high rates of significant-but-bogus effects, with the likelihood of obtaining at least one such bogus effect exceeding 50% in many experiments. We focus on two specific problems: using the grand average data to select the time windows and electrode sites for quantifying component amplitudes and latencies, and using one or more multi-factor statistical analyses. Re-analyses of prior data and simulations of typical experimental designs are used to show how these problems can greatly increase the likelihood of significant-but-bogus results. Several strategies are described for avoiding these problems and for increasing the likelihood that significant effects actually reflect true differences among groups or conditions. PMID:28000253

Significant Association of Urinary Toxic Metals and Autism-Related Symptoms—A Nonlinear Statistical Analysis with Cross Validation

PubMed Central

Adams, James; Kruger, Uwe; Geis, Elizabeth; Gehn, Eva; Fimbres, Valeria; Pollard, Elena; Mitchell, Jessica; Ingram, Julie; Hellmers, Robert; Quig, David; Hahn, Juergen

2017-01-01

Introduction A number of previous studies examined a possible association of toxic metals and autism, and over half of those studies suggest that toxic metal levels are different in individuals with Autism Spectrum Disorders (ASD). Additionally, several studies found that those levels correlate with the severity of ASD. Methods In order to further investigate these points, this paper performs the most detailed statistical analysis to date of a data set in this field. First morning urine samples were collected from 67 children and adults with ASD and 50 neurotypical controls of similar age and gender. The samples were analyzed to determine the levels of 10 urinary toxic metals (UTM). Autism-related symptoms were assessed with eleven behavioral measures. Statistical analysis was used to distinguish participants on the ASD spectrum and neurotypical participants based upon the UTM data alone. The analysis also included examining the association of autism severity with toxic metal excretion data using linear and nonlinear analysis. “Leave-one-out” cross-validation was used to ensure statistical independence of results. Results and Discussion Average excretion levels of several toxic metals (lead, tin, thallium, antimony) were significantly higher in the ASD group. However, ASD classification using univariate statistics proved difficult due to large variability, but nonlinear multivariate statistical analysis significantly improved ASD classification with Type I/II errors of 15% and 18%, respectively. These results clearly indicate that the urinary toxic metal excretion profiles of participants in the ASD group were significantly different from those of the neurotypical participants. Similarly, nonlinear methods determined a significantly stronger association between the behavioral measures and toxic metal excretion. The association was strongest for the Aberrant Behavior Checklist (including subscales on Irritability, Stereotypy, Hyperactivity, and Inappropriate

Cost-Effectiveness of Comprehensive School Reform in Low Achieving Schools

ERIC Educational Resources Information Center

Ross, John A.; Scott, Garth; Sibbald, Tim M.

2012-01-01

We evaluated the cost-effectiveness of Struggling Schools, a user-generated approach to Comprehensive School Reform implemented in 100 low achieving schools serving disadvantaged students in a Canadian province. The results show that while Struggling Schools had a statistically significant positive effect on Grade 3 Reading achievement, d = 0.48…

Educational Achievement and Black-White Inequality. Statistical Analysis Report.

ERIC Educational Resources Information Center

Jacobson, Jonathan; Olsen, Cara; Rice, Jennifer King; Sweetland, Stephen

This study explored relationships between black-white differences in educational achievement and black-white differences in various educational and economic outcomes. Three data sets examined the extent to which black-white differences in labor market outcomes, in educational attainment, and in mathematics and reading achievement were present for…

Full-Day Kindergarten Results in Significant Achievement Gains

ERIC Educational Resources Information Center

Raskin, Candace F.; Haar, Jean M.

2009-01-01

In 2004, after an in-depth review of student achievement data for over 4,000 students, the administration of a school district in southern Minnesota identified the following challenges: (1) above-state-average number of special education students; (2) increasing number of English as Second Language (ESL) students; (3) increasing number of students…

Statistical significance estimation of a signal within the GooFit framework on GPUs

NASA Astrophysics Data System (ADS)

Cristella, Leonardo; Di Florio, Adriano; Pompili, Alexis

2017-03-01

In order to test the computing capabilities of GPUs with respect to traditional CPU cores a high-statistics toy Monte Carlo technique has been implemented both in ROOT/RooFit and GooFit frameworks with the purpose to estimate the statistical significance of the structure observed by CMS close to the kinematical boundary of the J/ψϕ invariant mass in the three-body decay B+ → J/ψϕK+. GooFit is a data analysis open tool under development that interfaces ROOT/RooFit to CUDA platform on nVidia GPU. The optimized GooFit application running on GPUs hosted by servers in the Bari Tier2 provides striking speed-up performances with respect to the RooFit application parallelised on multiple CPUs by means of PROOF-Lite tool. The considerable resulting speed-up, evident when comparing concurrent GooFit processes allowed by CUDA Multi Process Service and a RooFit/PROOF-Lite process with multiple CPU workers, is presented and discussed in detail. By means of GooFit it has also been possible to explore the behaviour of a likelihood ratio test statistic in different situations in which the Wilks Theorem may or may not apply because its regularity conditions are not satisfied.

The intriguing evolution of effect sizes in biomedical research over time: smaller but more often statistically significant.

PubMed

Monsarrat, Paul; Vergnes, Jean-Noel

2018-01-01

In medicine, effect sizes (ESs) allow the effects of independent variables (including risk/protective factors or treatment interventions) on dependent variables (e.g., health outcomes) to be quantified. Given that many public health decisions and health care policies are based on ES estimates, it is important to assess how ESs are used in the biomedical literature and to investigate potential trends in their reporting over time. Through a big data approach, the text mining process automatically extracted 814 120 ESs from 13 322 754 PubMed abstracts. Eligible ESs were risk ratio, odds ratio, and hazard ratio, along with their confidence intervals. Here we show a remarkable decrease of ES values in PubMed abstracts between 1990 and 2015 while, concomitantly, results become more often statistically significant. Medians of ES values have decreased over time for both "risk" and "protective" values. This trend was found in nearly all fields of biomedical research, with the most marked downward tendency in genetics. Over the same period, the proportion of statistically significant ESs increased regularly: among the abstracts with at least 1 ES, 74% were statistically significant in 1990-1995, vs 85% in 2010-2015. whereas decreasing ESs could be an intrinsic evolution in biomedical research, the concomitant increase of statistically significant results is more intriguing. Although it is likely that growing sample sizes in biomedical research could explain these results, another explanation may lie in the "publish or perish" context of scientific research, with the probability of a growing orientation toward sensationalism in research reports. Important provisions must be made to improve the credibility of biomedical research and limit waste of resources. © The Authors 2017. Published by Oxford University Press.

Students' Perceptions of Computer-Based Learning Environments, Their Attitude towards Business Statistics, and Their Academic Achievement: Implications from a UK University

ERIC Educational Resources Information Center

Nguyen, ThuyUyen H.; Charity, Ian; Robson, Andrew

2016-01-01

This study investigates students' perceptions of computer-based learning environments, their attitude towards business statistics, and their academic achievement in higher education. Guided by learning environments concepts and attitudinal theory, a theoretical model was proposed with two instruments, one for measuring the learning environment and…

Testing earthquake prediction algorithms: Statistically significant advance prediction of the largest earthquakes in the Circum-Pacific, 1992-1997

USGS Publications Warehouse

Kossobokov, V.G.; Romashkova, L.L.; Keilis-Borok, V. I.; Healy, J.H.

1999-01-01

Algorithms M8 and MSc (i.e., the Mendocino Scenario) were used in a real-time intermediate-term research prediction of the strongest earthquakes in the Circum-Pacific seismic belt. Predictions are made by M8 first. Then, the areas of alarm are reduced by MSc at the cost that some earthquakes are missed in the second approximation of prediction. In 1992-1997, five earthquakes of magnitude 8 and above occurred in the test area: all of them were predicted by M8 and MSc identified correctly the locations of four of them. The space-time volume of the alarms is 36% and 18%, correspondingly, when estimated with a normalized product measure of empirical distribution of epicenters and uniform time. The statistical significance of the achieved results is beyond 99% both for M8 and MSc. For magnitude 7.5 + , 10 out of 19 earthquakes were predicted by M8 in 40% and five were predicted by M8-MSc in 13% of the total volume considered. This implies a significance level of 81% for M8 and 92% for M8-MSc. The lower significance levels might result from a global change in seismic regime in 1993-1996, when the rate of the largest events has doubled and all of them become exclusively normal or reversed faults. The predictions are fully reproducible; the algorithms M8 and MSc in complete formal definitions were published before we started our experiment [Keilis-Borok, V.I., Kossobokov, V.G., 1990. Premonitory activation of seismic flow: Algorithm M8, Phys. Earth and Planet. Inter. 61, 73-83; Kossobokov, V.G., Keilis-Borok, V.I., Smith, S.W., 1990. Localization of intermediate-term earthquake prediction, J. Geophys. Res., 95, 19763-19772; Healy, J.H., Kossobokov, V.G., Dewey, J.W., 1992. A test to evaluate the earthquake prediction algorithm, M8. U.S. Geol. Surv. OFR 92-401]. M8 is available from the IASPEI Software Library [Healy, J.H., Keilis-Borok, V.I., Lee, W.H.K. (Eds.), 1997. Algorithms for Earthquake Statistics and Prediction, Vol. 6. IASPEI Software Library]. ?? 1999 Elsevier

Tipping points in the arctic: eyeballing or statistical significance?

PubMed

Carstensen, Jacob; Weydmann, Agata

2012-02-01

Arctic ecosystems have experienced and are projected to experience continued large increases in temperature and declines in sea ice cover. It has been hypothesized that small changes in ecosystem drivers can fundamentally alter ecosystem functioning, and that this might be particularly pronounced for Arctic ecosystems. We present a suite of simple statistical analyses to identify changes in the statistical properties of data, emphasizing that changes in the standard error should be considered in addition to changes in mean properties. The methods are exemplified using sea ice extent, and suggest that the loss rate of sea ice accelerated by factor of ~5 in 1996, as reported in other studies, but increases in random fluctuations, as an early warning signal, were observed already in 1990. We recommend to employ the proposed methods more systematically for analyzing tipping points to document effects of climate change in the Arctic.

A Note on Comparing the Power of Test Statistics at Low Significance Levels.

PubMed

Morris, Nathan; Elston, Robert

2011-01-01

It is an obvious fact that the power of a test statistic is dependent upon the significance (alpha) level at which the test is performed. It is perhaps a less obvious fact that the relative performance of two statistics in terms of power is also a function of the alpha level. Through numerous personal discussions, we have noted that even some competent statisticians have the mistaken intuition that relative power comparisons at traditional levels such as α = 0.05 will be roughly similar to relative power comparisons at very low levels, such as the level α = 5 × 10 -8 , which is commonly used in genome-wide association studies. In this brief note, we demonstrate that this notion is in fact quite wrong, especially with respect to comparing tests with differing degrees of freedom. In fact, at very low alpha levels the cost of additional degrees of freedom is often comparatively low. Thus we recommend that statisticians exercise caution when interpreting the results of power comparison studies which use alpha levels that will not be used in practice.

Clinical significance of achieving a flexion limitation with a tension band system in grade 1 degenerative spondylolisthesis: a minimum 5-year follow-up.

PubMed

Lee, Sang-Ho; Lee, Ho-Yeon; Baek, Oon Ki; Bae, Jun Seok; Yoo, Seung-Hwa; Lee, June-Ho

2015-03-15

Retrospective clinical study. To evaluate the effect of the limitation of flexion rotation clinically and radiologically after interspinous soft stabilization using a tension band system in grade 1 degenerative spondylolisthesis. Although several studies have been published on the clinical effects of limiting rotatory motion using tension band systems, which mainly targets the limitation of flexion rather than that of extension, they were confined to the category of pedicle screw-based systems, revealing inconsistent long-term outcomes. Sixty-one patients with a mean age of 60.6 years (range, 28-76 yr) who underwent interspinous soft stabilization after decompression for grade 1 degenerative spondylolisthesis with stenosis between 2002 and 2004 were analyzed. At follow-up, the patients were divided into 2 groups on the basis of their achievement or failure to achieve flexion limitation. The clinical and radiological findings were analyzed. A multiple linear regression analysis was performed to determine the prognostic factors for surgical outcomes. At a mean follow-up duration of 72.5 months (range, 61-82 mo), 51 patients were classified into the flexion-limited group and 10 into the flexion-unlimited group. Statistically significant improvements were noted only in the flexion-limited group in all clinical scores. In the flexion-unlimited group, there were significant deteriorations in flexion angle (P = 0.009), axial thickness of the ligamentum flavum (P = 0.013), and the foraminal cross-sectional area (P = 0.011), resulting in significant intergroup differences. The preoperative extension angle was identified as the most influential variable for the flexion limitation and the clinical outcomes. The effects of the limitation of flexion rotation achieved through interspinous soft stabilization using a tension band system after decompression were related to the prevention of late recurrent stenosis and resultant radicular pain caused by flexion instability. The

Use of Tests of Statistical Significance and Other Analytic Choices in a School Psychology Journal: Review of Practices and Suggested Alternatives.

ERIC Educational Resources Information Center

Snyder, Patricia A.; Thompson, Bruce

The use of tests of statistical significance was explored, first by reviewing some criticisms of contemporary practice in the use of statistical tests as reflected in a series of articles in the "American Psychologist" and in the appointment of a "Task Force on Statistical Inference" by the American Psychological Association…

On Interestingness Measures for Mining Statistically Significant and Novel Clinical Associations from EMRs

PubMed Central

Abar, Orhan; Charnigo, Richard J.; Rayapati, Abner

2017-01-01

Association rule mining has received significant attention from both the data mining and machine learning communities. While data mining researchers focus more on designing efficient algorithms to mine rules from large datasets, the learning community has explored applications of rule mining to classification. A major problem with rule mining algorithms is the explosion of rules even for moderate sized datasets making it very difficult for end users to identify both statistically significant and potentially novel rules that could lead to interesting new insights and hypotheses. Researchers have proposed many domain independent interestingness measures using which, one can rank the rules and potentially glean useful rules from the top ranked ones. However, these measures have not been fully explored for rule mining in clinical datasets owing to the relatively large sizes of the datasets often encountered in healthcare and also due to limited access to domain experts for review/analysis. In this paper, using an electronic medical record (EMR) dataset of diagnoses and medications from over three million patient visits to the University of Kentucky medical center and affiliated clinics, we conduct a thorough evaluation of dozens of interestingness measures proposed in data mining literature, including some new composite measures. Using cumulative relevance metrics from information retrieval, we compare these interestingness measures against human judgments obtained from a practicing psychiatrist for association rules involving the depressive disorders class as the consequent. Our results not only surface new interesting associations for depressive disorders but also indicate classes of interestingness measures that weight rule novelty and statistical strength in contrasting ways, offering new insights for end users in identifying interesting rules. PMID:28736771

A randomized trial in a massive online open course shows people don't know what a statistically significant relationship looks like, but they can learn.

PubMed

Fisher, Aaron; Anderson, G Brooke; Peng, Roger; Leek, Jeff

2014-01-01

Scatterplots are the most common way for statisticians, scientists, and the public to visually detect relationships between measured variables. At the same time, and despite widely publicized controversy, P-values remain the most commonly used measure to statistically justify relationships identified between variables. Here we measure the ability to detect statistically significant relationships from scatterplots in a randomized trial of 2,039 students in a statistics massive open online course (MOOC). Each subject was shown a random set of scatterplots and asked to visually determine if the underlying relationships were statistically significant at the P < 0.05 level. Subjects correctly classified only 47.4% (95% CI [45.1%-49.7%]) of statistically significant relationships, and 74.6% (95% CI [72.5%-76.6%]) of non-significant relationships. Adding visual aids such as a best fit line or scatterplot smooth increased the probability a relationship was called significant, regardless of whether the relationship was actually significant. Classification of statistically significant relationships improved on repeat attempts of the survey, although classification of non-significant relationships did not. Our results suggest: (1) that evidence-based data analysis can be used to identify weaknesses in theoretical procedures in the hands of average users, (2) data analysts can be trained to improve detection of statistically significant results with practice, but (3) data analysts have incorrect intuition about what statistically significant relationships look like, particularly for small effects. We have built a web tool for people to compare scatterplots with their corresponding p-values which is available here: http://glimmer.rstudio.com/afisher/EDA/.

A randomized trial in a massive online open course shows people don’t know what a statistically significant relationship looks like, but they can learn

PubMed Central

Fisher, Aaron; Anderson, G. Brooke; Peng, Roger

2014-01-01

Scatterplots are the most common way for statisticians, scientists, and the public to visually detect relationships between measured variables. At the same time, and despite widely publicized controversy, P-values remain the most commonly used measure to statistically justify relationships identified between variables. Here we measure the ability to detect statistically significant relationships from scatterplots in a randomized trial of 2,039 students in a statistics massive open online course (MOOC). Each subject was shown a random set of scatterplots and asked to visually determine if the underlying relationships were statistically significant at the P < 0.05 level. Subjects correctly classified only 47.4% (95% CI [45.1%–49.7%]) of statistically significant relationships, and 74.6% (95% CI [72.5%–76.6%]) of non-significant relationships. Adding visual aids such as a best fit line or scatterplot smooth increased the probability a relationship was called significant, regardless of whether the relationship was actually significant. Classification of statistically significant relationships improved on repeat attempts of the survey, although classification of non-significant relationships did not. Our results suggest: (1) that evidence-based data analysis can be used to identify weaknesses in theoretical procedures in the hands of average users, (2) data analysts can be trained to improve detection of statistically significant results with practice, but (3) data analysts have incorrect intuition about what statistically significant relationships look like, particularly for small effects. We have built a web tool for people to compare scatterplots with their corresponding p-values which is available here: http://glimmer.rstudio.com/afisher/EDA/. PMID:25337457

The negative influence of significant others on high academic achieving school pupils' choice of nursing as a career.

PubMed

Neilson, Gavin R; McNally, Jim

2013-03-01

The International Council of Nurses proposes that the shortage of nurses is global in scale and is expected to become much worse in the years ahead. A major factor impacting on the worldwide nursing shortage is the diminishing number of young people choosing nursing as a career (International Council of Nurses, 2008). One important dimension of the school pupils' career choice process is their interactions with significant others and the influence of these significant others (Hodkinson and Sparkes, 1997). As Schools/Departments of Nursing endeavour to attract more intellectual school leavers it is important to examine what advice and opinions are significant others giving regarding nursing as a career choice and how influential is this advice. This paper is based on interview data from 20 high academic achieving 5th and 6th year school pupils in Scotland, paradigmatic cases from a larger sample, who had considered nursing as a possible career choice within their career preference cluster, but then later disregarded nursing and decided to pursue medicine or another health care profession. The data was particularly striking in revealing the negative influence of significant others on high academic achieving school pupils' choice of nursing as a career. The influence of significant others, these being specifically parents, guardians, guidance teachers and career advisors was very apparent in the data in that they had a very negative view regarding nursing as a career choice for high academic achieving school pupils. Copyright © 2012 Elsevier Ltd. All rights reserved.

Summary Statistics, Educational Achievement Gaps and the Ecological Fallacy

ERIC Educational Resources Information Center

Connolly, Paul

2006-01-01

Summary statistics continue to play an important role in identifying and monitoring patterns and trends in educational inequalities between differing groups of pupils over time. However, this article argues that their uncritical use can also encourage the labelling of whole groups of pupils as "underachievers" or…

The Effects of Various High School Scheduling Models on Student Achievement in Michigan

ERIC Educational Resources Information Center

Pickell, Russell E.

2017-01-01

This study reviews research and data to determine whether student achievement is affected by the high school scheduling model, and whether changes in scheduling models result in statistically significant changes in student achievement, as measured by the ACT Composite, ACT English Language Arts, and ACT Math scores. The high school scheduling…

Relationship between teacher preparedness and inquiry-based instructional practices to students' science achievement: Evidence from TIMSS 2007

NASA Astrophysics Data System (ADS)

Martin, Lynn A.

The purpose of this study was to examine the relationship between teachers' self-reported preparedness for teaching science content and their instructional practices to the science achievement of eighth grade science students in the United States as demonstrated by TIMSS 2007. Six hundred eighty-seven eighth grade science teachers in the United States representing 7,377 students responded to the TIMSS 2007 questionnaire about their instructional preparedness and their instructional practices. Quantitative data were reported. Through correlation analysis, the researcher found statistically significant positive relationships emerge between eighth grade science teachers' main area of study and their self-reported beliefs about their preparedness to teach that same content area. Another correlation analysis found a statistically significant negative relationship existed between teachers' self-reported use of inquiry-based instruction and preparedness to teach chemistry, physics and earth science. Another correlation analysis discovered a statistically significant positive relationship existed between physics preparedness and student science achievement. Finally, a correlation analysis found a statistically significant positive relationship existed between science teachers' self-reported implementation of inquiry-based instructional practices and student achievement. The data findings support the conclusion that teachers who have feelings of preparedness to teach science content and implement more inquiry-based instruction and less didactic instruction produce high achieving science students. As science teachers obtain the appropriate knowledge in science content and pedagogy, science teachers will feel prepared and will implement inquiry-based instruction in science classrooms.

The relationship between twelve-month home stimulation and school achievement.

PubMed

van Doorninck, W J; Caldwell, B M; Wright, C; Frankenburg, W K

1981-09-01

Home Observation for Measurement of the Environment (HOME) was designed to reflect parental support of early cognitive and socioemotional development. 12-month HOME scores were correlated with elementary school achievement, 5--9 years later. 50 low-income children were rank ordered by a weighted average of centile estimates of achievement test scores, letter grades, and curriculum levels in reading and math. 24 children were classified as having significant school achievement problems. The HOME total score correlated significantly, r = .37, with school centile scores among the low-income families. The statistically more appropriate contingency table analysis revealed a 68% correct classification rate and a significantly reduced error rate over random or blanket prediction. The results supported the predictive value of the 12-month HOME for school achievement among low-income families. In an additional sample of 21 middle-income families, there was insufficient variability among HOME scores to allow prediction. The HOME total scores were highly correlated, r = .86, among siblings tested at least 10 months apart.

Rapid Classification and Identification of Multiple Microorganisms with Accurate Statistical Significance via High-Resolution Tandem Mass Spectrometry

NASA Astrophysics Data System (ADS)

Alves, Gelio; Wang, Guanghui; Ogurtsov, Aleksey Y.; Drake, Steven K.; Gucek, Marjan; Sacks, David B.; Yu, Yi-Kuo

2018-06-01

Rapid and accurate identification and classification of microorganisms is of paramount importance to public health and safety. With the advance of mass spectrometry (MS) technology, the speed of identification can be greatly improved. However, the increasing number of microbes sequenced is complicating correct microbial identification even in a simple sample due to the large number of candidates present. To properly untwine candidate microbes in samples containing one or more microbes, one needs to go beyond apparent morphology or simple "fingerprinting"; to correctly prioritize the candidate microbes, one needs to have accurate statistical significance in microbial identification. We meet these challenges by using peptide-centric representations of microbes to better separate them and by augmenting our earlier analysis method that yields accurate statistical significance. Here, we present an updated analysis workflow that uses tandem MS (MS/MS) spectra for microbial identification or classification. We have demonstrated, using 226 MS/MS publicly available data files (each containing from 2500 to nearly 100,000 MS/MS spectra) and 4000 additional MS/MS data files, that the updated workflow can correctly identify multiple microbes at the genus and often the species level for samples containing more than one microbe. We have also shown that the proposed workflow computes accurate statistical significances, i.e., E values for identified peptides and unified E values for identified microbes. Our updated analysis workflow MiCId, a freely available software for Microorganism Classification and Identification, is available for download at https://www.ncbi.nlm.nih.gov/CBBresearch/Yu/downloads.html.

Rapid Classification and Identification of Multiple Microorganisms with Accurate Statistical Significance via High-Resolution Tandem Mass Spectrometry.

PubMed

Alves, Gelio; Wang, Guanghui; Ogurtsov, Aleksey Y; Drake, Steven K; Gucek, Marjan; Sacks, David B; Yu, Yi-Kuo

2018-06-05

Rapid and accurate identification and classification of microorganisms is of paramount importance to public health and safety. With the advance of mass spectrometry (MS) technology, the speed of identification can be greatly improved. However, the increasing number of microbes sequenced is complicating correct microbial identification even in a simple sample due to the large number of candidates present. To properly untwine candidate microbes in samples containing one or more microbes, one needs to go beyond apparent morphology or simple "fingerprinting"; to correctly prioritize the candidate microbes, one needs to have accurate statistical significance in microbial identification. We meet these challenges by using peptide-centric representations of microbes to better separate them and by augmenting our earlier analysis method that yields accurate statistical significance. Here, we present an updated analysis workflow that uses tandem MS (MS/MS) spectra for microbial identification or classification. We have demonstrated, using 226 MS/MS publicly available data files (each containing from 2500 to nearly 100,000 MS/MS spectra) and 4000 additional MS/MS data files, that the updated workflow can correctly identify multiple microbes at the genus and often the species level for samples containing more than one microbe. We have also shown that the proposed workflow computes accurate statistical significances, i.e., E values for identified peptides and unified E values for identified microbes. Our updated analysis workflow MiCId, a freely available software for Microorganism Classification and Identification, is available for download at https://www.ncbi.nlm.nih.gov/CBBresearch/Yu/downloads.html . Graphical Abstract ᅟ.

Teaching science in a technology rich environment: Probeware's effect on student attitude and achievement

NASA Astrophysics Data System (ADS)

Zelmanowicz, Marc

Purpose The use of technology in the science classroom has been a major part of the initiative toward increasing student attitude and achievement in Science, Technology, Education and Math [STEM] education in the United States. The purpose of this study was to determine the extent to which the use of probeware in a high school science living environment classroom impacts student attitude towards science and/or student achievement on standards-based assessments. This study sought to answer the following quantitative questions with a qualitative component: To what extent does the use of probeware in a high school level living environment course influence student attitudes toward science compared to students who are not using probeware? What is the impact, if any, on student achievement in a living environment course, as measured by New York State Living Environment Regents [NYSLER] exam grades, between students who use probeware and students who do not? Is there a significant difference between the two groups with regard to achieving mastery on the NYSLER exam? Sample The participants in the study were Living Environment students of a suburban high school outside of New York City. Methods The quasiexperimental study examined the effects of the replacement of traditional scientific equipment with probeware on student attitude and achievement in a living environment classroom. Student attitude was measured by the modified Attitude Toward Science Inventory [mATSI] and student achievement was measured by the New York State Living Environment Regents [NSLER] Exam. Descriptive statistics, ANCOVA and hierarchical regression analysis were conducted to answer the research questions in this study. A qualitative component was included to enhance the understanding of the quantitative analysis. Major Findings Through this study, results demonstrated a statistically significant impact of probeware on student attitude, but did not show a statistically significant impact of

The effects of modeling instruction on high school physics academic achievement

NASA Astrophysics Data System (ADS)

Wright, Tiffanie L.

The purpose of this study was to explore whether Modeling Instruction, compared to traditional lecturing, is an effective instructional method to promote academic achievement in selected high school physics classes at a rural middle Tennessee high school. This study used an ex post facto , quasi-experimental research methodology. The independent variables in this study were the instructional methods of teaching. The treatment variable was Modeling Instruction and the control variable was traditional lecture instruction. The Treatment Group consisted of participants in Physical World Concepts who received Modeling Instruction. The Control Group consisted of participants in Physical Science who received traditional lecture instruction. The dependent variable was gains scores on the Force Concepts Inventory (FCI). The participants for this study were 133 students each in both the Treatment and Control Groups (n = 266), who attended a public, high school in rural middle Tennessee. The participants were administered the Force Concepts Inventory (FCI) prior to being taught the mechanics of physics. The FCI data were entered into the computer-based Statistical Package for the Social Science (SPSS). Two independent samples t-tests were conducted to answer the research questions. There was a statistically significant difference between the treatment and control groups concerning the instructional method. Modeling Instructional methods were found to be effective in increasing the academic achievement of students in high school physics. There was no statistically significant difference between FCI gains scores for gender. Gender was found to have no effect on the academic achievement of students in high school physics classes. However, even though there was not a statistically significant difference, female students' gains scores were higher than male students' gains scores when Modeling Instructional methods of teaching were used. Based on these findings, it is recommended

Assessing Statistically Significant Heavy-Metal Concentrations in Abandoned Mine Areas via Hot Spot Analysis of Portable XRF Data

PubMed Central

Kim, Sung-Min; Choi, Yosoon

2017-01-01

To develop appropriate measures to prevent soil contamination in abandoned mining areas, an understanding of the spatial variation of the potentially toxic trace elements (PTEs) in the soil is necessary. For the purpose of effective soil sampling, this study uses hot spot analysis, which calculates a z-score based on the Getis-Ord Gi* statistic to identify a statistically significant hot spot sample. To constitute a statistically significant hot spot, a feature with a high value should also be surrounded by other features with high values. Using relatively cost- and time-effective portable X-ray fluorescence (PXRF) analysis, sufficient input data are acquired from the Busan abandoned mine and used for hot spot analysis. To calibrate the PXRF data, which have a relatively low accuracy, the PXRF analysis data are transformed using the inductively coupled plasma atomic emission spectrometry (ICP-AES) data. The transformed PXRF data of the Busan abandoned mine are classified into four groups according to their normalized content and z-scores: high content with a high z-score (HH), high content with a low z-score (HL), low content with a high z-score (LH), and low content with a low z-score (LL). The HL and LH cases may be due to measurement errors. Additional or complementary surveys are required for the areas surrounding these suspect samples or for significant hot spot areas. The soil sampling is conducted according to a four-phase procedure in which the hot spot analysis and proposed group classification method are employed to support the development of a sampling plan for the following phase. Overall, 30, 50, 80, and 100 samples are investigated and analyzed in phases 1–4, respectively. The method implemented in this case study may be utilized in the field for the assessment of statistically significant soil contamination and the identification of areas for which an additional survey is required. PMID:28629168

Assessing Statistically Significant Heavy-Metal Concentrations in Abandoned Mine Areas via Hot Spot Analysis of Portable XRF Data.

PubMed

Kim, Sung-Min; Choi, Yosoon

2017-06-18

To develop appropriate measures to prevent soil contamination in abandoned mining areas, an understanding of the spatial variation of the potentially toxic trace elements (PTEs) in the soil is necessary. For the purpose of effective soil sampling, this study uses hot spot analysis, which calculates a z -score based on the Getis-Ord Gi* statistic to identify a statistically significant hot spot sample. To constitute a statistically significant hot spot, a feature with a high value should also be surrounded by other features with high values. Using relatively cost- and time-effective portable X-ray fluorescence (PXRF) analysis, sufficient input data are acquired from the Busan abandoned mine and used for hot spot analysis. To calibrate the PXRF data, which have a relatively low accuracy, the PXRF analysis data are transformed using the inductively coupled plasma atomic emission spectrometry (ICP-AES) data. The transformed PXRF data of the Busan abandoned mine are classified into four groups according to their normalized content and z -scores: high content with a high z -score (HH), high content with a low z -score (HL), low content with a high z -score (LH), and low content with a low z -score (LL). The HL and LH cases may be due to measurement errors. Additional or complementary surveys are required for the areas surrounding these suspect samples or for significant hot spot areas. The soil sampling is conducted according to a four-phase procedure in which the hot spot analysis and proposed group classification method are employed to support the development of a sampling plan for the following phase. Overall, 30, 50, 80, and 100 samples are investigated and analyzed in phases 1-4, respectively. The method implemented in this case study may be utilized in the field for the assessment of statistically significant soil contamination and the identification of areas for which an additional survey is required.

Attitudes toward statistics in medical postgraduates: measuring, evaluating and monitoring.

PubMed

Zhang, Yuhai; Shang, Lei; Wang, Rui; Zhao, Qinbo; Li, Chanjuan; Xu, Yongyong; Su, Haixia

2012-11-23

In medical training, statistics is considered a very difficult course to learn and teach. Current studies have found that students' attitudes toward statistics can influence their learning process. Measuring, evaluating and monitoring the changes of students' attitudes toward statistics are important. Few studies have focused on the attitudes of postgraduates, especially medical postgraduates. Our purpose was to understand current attitudes regarding statistics held by medical postgraduates and explore their effects on students' achievement. We also wanted to explore the influencing factors and the sources of these attitudes and monitor their changes after a systematic statistics course. A total of 539 medical postgraduates enrolled in a systematic statistics course completed the pre-form of the Survey of Attitudes Toward Statistics -28 scale, and 83 postgraduates were selected randomly from among them to complete the post-form scale after the course. Most medical postgraduates held positive attitudes toward statistics, but they thought statistics was a very difficult subject. The attitudes mainly came from experiences in a former statistical or mathematical class. Age, level of statistical education, research experience, specialty and mathematics basis may influence postgraduate attitudes toward statistics. There were significant positive correlations between course achievement and attitudes toward statistics. In general, student attitudes showed negative changes after completing a statistics course. The importance of student attitudes toward statistics must be recognized in medical postgraduate training. To make sure all students have a positive learning environment, statistics teachers should measure their students' attitudes and monitor their change of status during a course. Some necessary assistance should be offered for those students who develop negative attitudes.

Inverse statistics and information content

NASA Astrophysics Data System (ADS)

Ebadi, H.; Bolgorian, Meysam; Jafari, G. R.

2010-12-01

Inverse statistics analysis studies the distribution of investment horizons to achieve a predefined level of return. This distribution provides a maximum investment horizon which determines the most likely horizon for gaining a specific return. There exists a significant difference between inverse statistics of financial market data and a fractional Brownian motion (fBm) as an uncorrelated time-series, which is a suitable criteria to measure information content in financial data. In this paper we perform this analysis for the DJIA and S&P500 as two developed markets and Tehran price index (TEPIX) as an emerging market. We also compare these probability distributions with fBm probability, to detect when the behavior of the stocks are the same as fBm.

The role of baryons in creating statistically significant planes of satellites around Milky Way-mass galaxies

NASA Astrophysics Data System (ADS)

Ahmed, Sheehan H.; Brooks, Alyson M.; Christensen, Charlotte R.

2017-04-01

We investigate whether the inclusion of baryonic physics influences the formation of thin, coherently rotating planes of satellites such as those seen around the Milky Way and Andromeda. For four Milky Way-mass simulations, each run both as dark matter-only and with baryons included, we are able to identify a planar configuration that significantly maximizes the number of plane satellite members. The maximum plane member satellites are consistently different between the dark matter-only and baryonic versions of the same run due to the fact that satellites are both more likely to be destroyed and to infall later in the baryonic runs. Hence, studying satellite planes in dark matter-only simulations is misleading, because they will be composed of different satellite members than those that would exist if baryons were included. Additionally, the destruction of satellites in the baryonic runs leads to less radially concentrated satellite distributions, a result that is critical to making planes that are statistically significant compared to a random distribution. Since all planes pass through the centre of the galaxy, it is much harder to create a plane of a given height from a random distribution if the satellites have a low radial concentration. We identify Andromeda's low radial satellite concentration as a key reason why the plane in Andromeda is highly significant. Despite this, when corotation is considered, none of the satellite planes identified for the simulated galaxies are as statistically significant as the observed planes around the Milky Way and Andromeda, even in the baryonic runs.

Which Variables Associated with Data-Driven Instruction Are Believed to Best Predict Urban Student Achievement?

ERIC Educational Resources Information Center

Greer, Wil

2013-01-01

This study identified the variables associated with data-driven instruction (DDI) that are perceived to best predict student achievement. Of the DDI variables discussed in the literature, 51 of them had a sufficient enough research base to warrant statistical analysis. Of them, 26 were statistically significant. Multiple regression and an…

Explaining Student Achievement: The Influence of Teachers' Pedagogical Content Knowledge in Statistics

ERIC Educational Resources Information Center

Callingham, Rosemary; Carmichael, Colin; Watson, Jane M.

2016-01-01

Statistics is an increasingly important component of the mathematics curriculum. "StatSmart" was a project intended to influence middle-years students' learning outcomes in statistics through the provision of appropriate professional learning opportunities and technology to teachers. Participating students in grade 5/6 to grade 9…

"Clinical" Significance: "Clinical" Significance and "Practical" Significance are NOT the Same Things

ERIC Educational Resources Information Center

Peterson, Lisa S.

2008-01-01

Clinical significance is an important concept in research, particularly in education and the social sciences. The present article first compares clinical significance to other measures of "significance" in statistics. The major methods used to determine clinical significance are explained and the strengths and weaknesses of clinical significance…

The distribution of P-values in medical research articles suggested selective reporting associated with statistical significance.

PubMed

Perneger, Thomas V; Combescure, Christophe

2017-07-01

Published P-values provide a window into the global enterprise of medical research. The aim of this study was to use the distribution of published P-values to estimate the relative frequencies of null and alternative hypotheses and to seek irregularities suggestive of publication bias. This cross-sectional study included P-values published in 120 medical research articles in 2016 (30 each from the BMJ, JAMA, Lancet, and New England Journal of Medicine). The observed distribution of P-values was compared with expected distributions under the null hypothesis (i.e., uniform between 0 and 1) and the alternative hypothesis (strictly decreasing from 0 to 1). P-values were categorized according to conventional levels of statistical significance and in one-percent intervals. Among 4,158 recorded P-values, 26.1% were highly significant (P < 0.001), 9.1% were moderately significant (P ≥ 0.001 to < 0.01), 11.7% were weakly significant (P ≥ 0.01 to < 0.05), and 53.2% were nonsignificant (P ≥ 0.05). We noted three irregularities: (1) high proportion of P-values <0.001, especially in observational studies, (2) excess of P-values equal to 1, and (3) about twice as many P-values less than 0.05 compared with those more than 0.05. The latter finding was seen in both randomized trials and observational studies, and in most types of analyses, excepting heterogeneity tests and interaction tests. Under plausible assumptions, we estimate that about half of the tested hypotheses were null and the other half were alternative. This analysis suggests that statistical tests published in medical journals are not a random sample of null and alternative hypotheses but that selective reporting is prevalent. In particular, significant results are about twice as likely to be reported as nonsignificant results. Copyright © 2017 Elsevier Inc. All rights reserved.

The thresholds for statistical and clinical significance – a five-step procedure for evaluation of intervention effects in randomised clinical trials

PubMed Central

2014-01-01

Background Thresholds for statistical significance are insufficiently demonstrated by 95% confidence intervals or P-values when assessing results from randomised clinical trials. First, a P-value only shows the probability of getting a result assuming that the null hypothesis is true and does not reflect the probability of getting a result assuming an alternative hypothesis to the null hypothesis is true. Second, a confidence interval or a P-value showing significance may be caused by multiplicity. Third, statistical significance does not necessarily result in clinical significance. Therefore, assessment of intervention effects in randomised clinical trials deserves more rigour in order to become more valid. Methods Several methodologies for assessing the statistical and clinical significance of intervention effects in randomised clinical trials were considered. Balancing simplicity and comprehensiveness, a simple five-step procedure was developed. Results For a more valid assessment of results from a randomised clinical trial we propose the following five-steps: (1) report the confidence intervals and the exact P-values; (2) report Bayes factor for the primary outcome, being the ratio of the probability that a given trial result is compatible with a ‘null’ effect (corresponding to the P-value) divided by the probability that the trial result is compatible with the intervention effect hypothesised in the sample size calculation; (3) adjust the confidence intervals and the statistical significance threshold if the trial is stopped early or if interim analyses have been conducted; (4) adjust the confidence intervals and the P-values for multiplicity due to number of outcome comparisons; and (5) assess clinical significance of the trial results. Conclusions If the proposed five-step procedure is followed, this may increase the validity of assessments of intervention effects in randomised clinical trials. PMID:24588900

A Probabilistic Model of Local Sequence Alignment That Simplifies Statistical Significance Estimation

PubMed Central

Eddy, Sean R.

2008-01-01

Sequence database searches require accurate estimation of the statistical significance of scores. Optimal local sequence alignment scores follow Gumbel distributions, but determining an important parameter of the distribution (λ) requires time-consuming computational simulation. Moreover, optimal alignment scores are less powerful than probabilistic scores that integrate over alignment uncertainty (“Forward” scores), but the expected distribution of Forward scores remains unknown. Here, I conjecture that both expected score distributions have simple, predictable forms when full probabilistic modeling methods are used. For a probabilistic model of local sequence alignment, optimal alignment bit scores (“Viterbi” scores) are Gumbel-distributed with constant λ = log 2, and the high scoring tail of Forward scores is exponential with the same constant λ. Simulation studies support these conjectures over a wide range of profile/sequence comparisons, using 9,318 profile-hidden Markov models from the Pfam database. This enables efficient and accurate determination of expectation values (E-values) for both Viterbi and Forward scores for probabilistic local alignments. PMID:18516236

Scan statistics with local vote for target detection in distributed system

NASA Astrophysics Data System (ADS)

Luo, Junhai; Wu, Qi

2017-12-01

Target detection has occupied a pivotal position in distributed system. Scan statistics, as one of the most efficient detection methods, has been applied to a variety of anomaly detection problems and significantly improves the probability of detection. However, scan statistics cannot achieve the expected performance when the noise intensity is strong, or the signal emitted by the target is weak. The local vote algorithm can also achieve higher target detection rate. After the local vote, the counting rule is always adopted for decision fusion. The counting rule does not use the information about the contiguity of sensors but takes all sensors' data into consideration, which makes the result undesirable. In this paper, we propose a scan statistics with local vote (SSLV) method. This method combines scan statistics with local vote decision. Before scan statistics, each sensor executes local vote decision according to the data of its neighbors and its own. By combining the advantages of both, our method can obtain higher detection rate in low signal-to-noise ratio environment than the scan statistics. After the local vote decision, the distribution of sensors which have detected the target becomes more intensive. To make full use of local vote decision, we introduce a variable-step-parameter for the SSLV. It significantly shortens the scan period especially when the target is absent. Analysis and simulations are presented to demonstrate the performance of our method.

Attitudes toward statistics in medical postgraduates: measuring, evaluating and monitoring

PubMed Central

2012-01-01

Background In medical training, statistics is considered a very difficult course to learn and teach. Current studies have found that students’ attitudes toward statistics can influence their learning process. Measuring, evaluating and monitoring the changes of students’ attitudes toward statistics are important. Few studies have focused on the attitudes of postgraduates, especially medical postgraduates. Our purpose was to understand current attitudes regarding statistics held by medical postgraduates and explore their effects on students’ achievement. We also wanted to explore the influencing factors and the sources of these attitudes and monitor their changes after a systematic statistics course. Methods A total of 539 medical postgraduates enrolled in a systematic statistics course completed the pre-form of the Survey of Attitudes Toward Statistics −28 scale, and 83 postgraduates were selected randomly from among them to complete the post-form scale after the course. Results Most medical postgraduates held positive attitudes toward statistics, but they thought statistics was a very difficult subject. The attitudes mainly came from experiences in a former statistical or mathematical class. Age, level of statistical education, research experience, specialty and mathematics basis may influence postgraduate attitudes toward statistics. There were significant positive correlations between course achievement and attitudes toward statistics. In general, student attitudes showed negative changes after completing a statistics course. Conclusions The importance of student attitudes toward statistics must be recognized in medical postgraduate training. To make sure all students have a positive learning environment, statistics teachers should measure their students’ attitudes and monitor their change of status during a course. Some necessary assistance should be offered for those students who develop negative attitudes. PMID:23173770

Conducting tests for statistically significant differences using forest inventory data

Treesearch

James A. Westfall; Scott A. Pugh; John W. Coulston

2013-01-01

Many forest inventory and monitoring programs are based on a sample of ground plots from which estimates of forest resources are derived. In addition to evaluating metrics such as number of trees or amount of cubic wood volume, it is often desirable to make comparisons between resource attributes. To properly conduct statistical tests for differences, it is imperative...

An Analysis of Mathematics Course Sequences for Low Achieving Students at a Comprehensive Technical High School

ERIC Educational Resources Information Center

Edge, D. Michael

2011-01-01

This non-experimental study attempted to determine how the different prescribed mathematic tracks offered at a comprehensive technical high school influenced the mathematics performance of low-achieving students on standardized assessments of mathematics achievement. The goal was to provide an analysis of any statistically significant differences…

Teaching Statistics in Integration with Psychology

ERIC Educational Resources Information Center

Wiberg, Marie

2009-01-01

The aim was to revise a statistics course in order to get the students motivated to learn statistics and to integrate statistics more throughout a psychology course. Further, we wish to make students become more interested in statistics and to help them see the importance of using statistics in psychology research. To achieve this goal, several…

Statistical significance of seasonal warming/cooling trends

NASA Astrophysics Data System (ADS)

Ludescher, Josef; Bunde, Armin; Schellnhuber, Hans Joachim

2017-04-01

The question whether a seasonal climate trend (e.g., the increase of summer temperatures in Antarctica in the last decades) is of anthropogenic or natural origin is of great importance for mitigation and adaption measures alike. The conventional significance analysis assumes that (i) the seasonal climate trends can be quantified by linear regression, (ii) the different seasonal records can be treated as independent records, and (iii) the persistence in each of these seasonal records can be characterized by short-term memory described by an autoregressive process of first order. Here we show that assumption ii is not valid, due to strong intraannual correlations by which different seasons are correlated. We also show that, even in the absence of correlations, for Gaussian white noise, the conventional analysis leads to a strong overestimation of the significance of the seasonal trends, because multiple testing has not been taken into account. In addition, when the data exhibit long-term memory (which is the case in most climate records), assumption iii leads to a further overestimation of the trend significance. Combining Monte Carlo simulations with the Holm-Bonferroni method, we demonstrate how to obtain reliable estimates of the significance of the seasonal climate trends in long-term correlated records. For an illustration, we apply our method to representative temperature records from West Antarctica, which is one of the fastest-warming places on Earth and belongs to the crucial tipping elements in the Earth system.

Why Current Statistics of Complementary Alternative Medicine Clinical Trials is Invalid.

PubMed

Pandolfi, Maurizio; Carreras, Giulia

2018-06-07

It is not sufficiently known that frequentist statistics cannot provide direct information on the probability that the research hypothesis tested is correct. The error resulting from this misunderstanding is compounded when the hypotheses under scrutiny have precarious scientific bases, which, generally, those of complementary alternative medicine (CAM) are. In such cases, it is mandatory to use inferential statistics, considering the prior probability that the hypothesis tested is true, such as the Bayesian statistics. The authors show that, under such circumstances, no real statistical significance can be achieved in CAM clinical trials. In this respect, CAM trials involving human material are also hardly defensible from an ethical viewpoint.

Environmental Health Practice: Statistically Based Performance Measurement

PubMed Central

Enander, Richard T.; Gagnon, Ronald N.; Hanumara, R. Choudary; Park, Eugene; Armstrong, Thomas; Gute, David M.

2007-01-01

Objectives. State environmental and health protection agencies have traditionally relied on a facility-by-facility inspection-enforcement paradigm to achieve compliance with government regulations. We evaluated the effectiveness of a new approach that uses a self-certification random sampling design. Methods. Comprehensive environmental and occupational health data from a 3-year statewide industry self-certification initiative were collected from representative automotive refinishing facilities located in Rhode Island. Statistical comparisons between baseline and postintervention data facilitated a quantitative evaluation of statewide performance. Results. The analysis of field data collected from 82 randomly selected automotive refinishing facilities showed statistically significant improvements (P<.05, Fisher exact test) in 4 major performance categories: occupational health and safety, air pollution control, hazardous waste management, and wastewater discharge. Statistical significance was also shown when a modified Bonferroni adjustment for multiple comparisons was performed. Conclusions. Our findings suggest that the new self-certification approach to environmental and worker protection is effective and can be used as an adjunct to further enhance state and federal enforcement programs. PMID:17267709

A Network-Based Method to Assess the Statistical Significance of Mild Co-Regulation Effects

PubMed Central

Horvát, Emőke-Ágnes; Zhang, Jitao David; Uhlmann, Stefan; Sahin, Özgür; Zweig, Katharina Anna

2013-01-01

Recent development of high-throughput, multiplexing technology has initiated projects that systematically investigate interactions between two types of components in biological networks, for instance transcription factors and promoter sequences, or microRNAs (miRNAs) and mRNAs. In terms of network biology, such screening approaches primarily attempt to elucidate relations between biological components of two distinct types, which can be represented as edges between nodes in a bipartite graph. However, it is often desirable not only to determine regulatory relationships between nodes of different types, but also to understand the connection patterns of nodes of the same type. Especially interesting is the co-occurrence of two nodes of the same type, i.e., the number of their common neighbours, which current high-throughput screening analysis fails to address. The co-occurrence gives the number of circumstances under which both of the biological components are influenced in the same way. Here we present SICORE, a novel network-based method to detect pairs of nodes with a statistically significant co-occurrence. We first show the stability of the proposed method on artificial data sets: when randomly adding and deleting observations we obtain reliable results even with noise exceeding the expected level in large-scale experiments. Subsequently, we illustrate the viability of the method based on the analysis of a proteomic screening data set to reveal regulatory patterns of human microRNAs targeting proteins in the EGFR-driven cell cycle signalling system. Since statistically significant co-occurrence may indicate functional synergy and the mechanisms underlying canalization, and thus hold promise in drug target identification and therapeutic development, we provide a platform-independent implementation of SICORE with a graphical user interface as a novel tool in the arsenal of high-throughput screening analysis. PMID:24039936

Psychophysical Map Stability in Bilateral Sequential Cochlear Implantation: Comparing Current Audiology Methods to a New Statistical Definition.

PubMed

Domville-Lewis, Chloe; Santa Maria, Peter L; Upson, Gemma; Chester-Browne, Ronel; Atlas, Marcus D

2015-01-01

The purpose of this study was to establish a statistical definition for stability in cochlear implant maps. Once defined, this study aimed to compare the duration taken to achieve a stable map in first and second implants in patients who underwent sequential bilateral cochlear implantation. This article also sought to evaluate a number of factors that potentially affect map stability. A retrospective cohort study of 33 patients with sensorineural hearing loss who received sequential bilateral cochlear implantation (Cochlear, Sydney, Australia), performed by the senior author. Psychophysical parameters of hearing threshold scores, comfort scores, and the dynamic range were measured for the apical, medial, and basal portions of the cochlear implant electrode at a range of intervals postimplantation. Stability was defined statistically as a less than 10% difference in threshold, comfort, and dynamic range scores over three consecutive mapping sessions. A senior cochlear implant audiologist, blinded to implant order and the statistical results, separately analyzed these psychophysical map parameters using current assessment methods. First and second implants were compared for duration to achieve stability, age, gender, the duration of deafness, etiology of deafness, time between the insertion of the first and second implant, and the presence or absence of preoperative hearing aids were evaluated and its relationship to stability. Statistical analysis included performing a two-tailed Student's t tests and least squares regression analysis, with a statistical significance set at p ≤ 0.05. There was a significant positive correlation between the devised statistical definition and the current audiology methods for assessing stability, with a Pearson correlation coefficient r = 0.36 and a least squares regression slope (b) of 0.41, df(58), 95% confidence interval 0.07 to 0.55 (p = 0.004). The average duration from device switch on to stability in the first implant was 87

Synthetic velocity gradient tensors and the identification of statistically significant aspects of the structure of turbulence

NASA Astrophysics Data System (ADS)

Keylock, Christopher J.

2017-08-01

A method is presented for deriving random velocity gradient tensors given a source tensor. These synthetic tensors are constrained to lie within mathematical bounds of the non-normality of the source tensor, but we do not impose direct constraints upon scalar quantities typically derived from the velocity gradient tensor and studied in fluid mechanics. Hence, it becomes possible to ask hypotheses of data at a point regarding the statistical significance of these scalar quantities. Having presented our method and the associated mathematical concepts, we apply it to homogeneous, isotropic turbulence to test the utility of the approach for a case where the behavior of the tensor is understood well. We show that, as well as the concentration of data along the Vieillefosse tail, actual turbulence is also preferentially located in the quadrant where there is both excess enstrophy (Q>0 ) and excess enstrophy production (R<0 ). We also examine the topology implied by the strain eigenvalues and find that for the statistically significant results there is a particularly strong relative preference for the formation of disklike structures in the (Q<0 ,R<0 ) quadrant. With the method shown to be useful for a turbulence that is already understood well, it should be of even greater utility for studying complex flows seen in industry and the environment.

A SUMMARY OF STUDIES IN ACHIEVEMENT OF VOCATIONAL AGRICULTURE GRADUATES IN COLLEGE.

ERIC Educational Resources Information Center

MCCLELLAND, JOHN B.

TWENTY-SEVEN STUDIES ARE INCLUDED IN THIS SYNTHESIS OF RESEARCH ON THE APPROPRIATENESS OF HIGH SCHOOL VOCATIONAL AGRICULTURE STUDENTS GOING ON TO AGRICULTURAL COLLEGES. MOST OF THE STUDIES INVOLVED STATISTICAL SIGNIFICANCE TREATMENT. THE STUDIES ARE ORGANIZED INTO SECTIONS--(1) COMPREHENSIVE, (2) ACHIEVEMENT IN LEADERSHIP ACTIVITIES, (3)…

A simulation study of the strength of evidence in the recommendation of medications based on two trials with statistically significant results

PubMed Central

Ioannidis, John P. A.

2017-01-01

A typical rule that has been used for the endorsement of new medications by the Food and Drug Administration is to have two trials, each convincing on its own, demonstrating effectiveness. “Convincing” may be subjectively interpreted, but the use of p-values and the focus on statistical significance (in particular with p < .05 being coined significant) is pervasive in clinical research. Therefore, in this paper, we calculate with simulations what it means to have exactly two trials, each with p < .05, in terms of the actual strength of evidence quantified by Bayes factors. Our results show that different cases where two trials have a p-value below .05 have wildly differing Bayes factors. Bayes factors of at least 20 in favor of the alternative hypothesis are not necessarily achieved and they fail to be reached in a large proportion of cases, in particular when the true effect size is small (0.2 standard deviations) or zero. In a non-trivial number of cases, evidence actually points to the null hypothesis, in particular when the true effect size is zero, when the number of trials is large, and when the number of participants in both groups is low. We recommend use of Bayes factors as a routine tool to assess endorsement of new medications, because Bayes factors consistently quantify strength of evidence. Use of p-values may lead to paradoxical and spurious decision-making regarding the use of new medications. PMID:28273140

Statistical Significance of Periodicity and Log-Periodicity with Heavy-Tailed Correlated Noise

NASA Astrophysics Data System (ADS)

Zhou, Wei-Xing; Sornette, Didier

We estimate the probability that random noise, of several plausible standard distributions, creates a false alarm that a periodicity (or log-periodicity) is found in a time series. The solution of this problem is already known for independent Gaussian distributed noise. We investigate more general situations with non-Gaussian correlated noises and present synthetic tests on the detectability and statistical significance of periodic components. A periodic component of a time series is usually detected by some sort of Fourier analysis. Here, we use the Lomb periodogram analysis, which is suitable and outperforms Fourier transforms for unevenly sampled time series. We examine the false-alarm probability of the largest spectral peak of the Lomb periodogram in the presence of power-law distributed noises, of short-range and of long-range fractional-Gaussian noises. Increasing heavy-tailness (respectively correlations describing persistence) tends to decrease (respectively increase) the false-alarm probability of finding a large spurious Lomb peak. Increasing anti-persistence tends to decrease the false-alarm probability. We also study the interplay between heavy-tailness and long-range correlations. In order to fully determine if a Lomb peak signals a genuine rather than a spurious periodicity, one should in principle characterize the Lomb peak height, its width and its relations to other peaks in the complete spectrum. As a step towards this full characterization, we construct the joint-distribution of the frequency position (relative to other peaks) and of the height of the highest peak of the power spectrum. We also provide the distributions of the ratio of the highest Lomb peak to the second highest one. Using the insight obtained by the present statistical study, we re-examine previously reported claims of ``log-periodicity'' and find that the credibility for log-periodicity in 2D-freely decaying turbulence is weakened while it is strengthened for fracture, for the

Statistical downscaling rainfall using artificial neural network: significantly wetter Bangkok?

NASA Astrophysics Data System (ADS)

Vu, Minh Tue; Aribarg, Thannob; Supratid, Siriporn; Raghavan, Srivatsan V.; Liong, Shie-Yui

2016-11-01

Artificial neural network (ANN) is an established technique with a flexible mathematical structure that is capable of identifying complex nonlinear relationships between input and output data. The present study utilizes ANN as a method of statistically downscaling global climate models (GCMs) during the rainy season at meteorological site locations in Bangkok, Thailand. The study illustrates the applications of the feed forward back propagation using large-scale predictor variables derived from both the ERA-Interim reanalyses data and present day/future GCM data. The predictors are first selected over different grid boxes surrounding Bangkok region and then screened by using principal component analysis (PCA) to filter the best correlated predictors for ANN training. The reanalyses downscaled results of the present day climate show good agreement against station precipitation with a correlation coefficient of 0.8 and a Nash-Sutcliffe efficiency of 0.65. The final downscaled results for four GCMs show an increasing trend of precipitation for rainy season over Bangkok by the end of the twenty-first century. The extreme values of precipitation determined using statistical indices show strong increases of wetness. These findings will be useful for policy makers in pondering adaptation measures due to flooding such as whether the current drainage network system is sufficient to meet the changing climate and to plan for a range of related adaptation/mitigation measures.

Statistical trend analysis and extreme distribution of significant wave height from 1958 to 1999 - an application to the Italian Seas

NASA Astrophysics Data System (ADS)

Martucci, G.; Carniel, S.; Chiggiato, J.; Sclavo, M.; Lionello, P.; Galati, M. B.

2010-06-01

The study is a statistical analysis of sea states timeseries derived using the wave model WAM forced by the ERA-40 dataset in selected areas near the Italian coasts. For the period 1 January 1958 to 31 December 1999 the analysis yields: (i) the existence of a negative trend in the annual- and winter-averaged sea state heights; (ii) the existence of a turning-point in late 80's in the annual-averaged trend of sea state heights at a site in the Northern Adriatic Sea; (iii) the overall absence of a significant trend in the annual-averaged mean durations of sea states over thresholds; (iv) the assessment of the extreme values on a time-scale of thousand years. The analysis uses two methods to obtain samples of extremes from the independent sea states: the r-largest annual maxima and the peak-over-threshold. The two methods show statistical differences in retrieving the return values and more generally in describing the significant wave field. The r-largest annual maxima method provides more reliable predictions of the extreme values especially for small return periods (<100 years). Finally, the study statistically proves the existence of decadal negative trends in the significant wave heights and by this it conveys useful information on the wave climatology of the Italian seas during the second half of the 20th century.

The Surprisingly Modest Relationship between SES and Educational Achievement

ERIC Educational Resources Information Center

Harwell, Michael; Maeda, Yukiko; Bishop, Kyoungwon; Xie, Aolin

2017-01-01

Measures of socioeconomic status (SES) are routinely used in analyses of achievement data to increase statistical power, statistically control for the effects of SES, and enhance causality arguments under the premise that the SES-achievement relationship is moderate to strong. Empirical evidence characterizing the strength of the SES-achievement…

On the statistical significance of excess events: Remarks of caution and the need for a standard method of calculation

NASA Technical Reports Server (NTRS)

Staubert, R.

1985-01-01

Methods for calculating the statistical significance of excess events and the interpretation of the formally derived values are discussed. It is argued that a simple formula for a conservative estimate should generally be used in order to provide a common understanding of quoted values.

Learning Outcomes in a Laboratory Environment vs. Classroom for Statistics Instruction: An Alternative Approach Using Statistical Software

ERIC Educational Resources Information Center

McCulloch, Ryan Sterling

2017-01-01

The role of any statistics course is to increase the understanding and comprehension of statistical concepts and those goals can be achieved via both theoretical instruction and statistical software training. However, many introductory courses either forego advanced software usage, or leave its use to the student as a peripheral activity. The…

The Development of Statistical Literacy Skills in the Eighth Grade: Exploring the TIMSS Data to Evaluate Student Achievement and Teacher Characteristics in the United States

ERIC Educational Resources Information Center

Mills, Jamie D.; Holloway, Charles E.

2013-01-01

This study investigated the relationship between student achievement in statistics and factors at the student and teacher/classroom levels using the US 8th-grade Data and Chance content domain from the Trends in International Mathematics and Science Study, 2007 (TIMSS, 2007). Using variables that have been linked to mathematics and statistics…

The Impact of Learning Styles on Student Achievement in a Web-Based versus an Equivalent Face-to-Face Course

ERIC Educational Resources Information Center

Zacharis, Nick Z.

2010-01-01

This study investigated the relationship between students' learning styles and their achievement in two different learning environments: online instruction and traditional instruction. The results indicated that a) students in the traditional learning group had higher, but not statistically significant higher, levels of achievement than students…

The Necessity of the Hippocampus for Statistical Learning

PubMed Central

Covington, Natalie V.; Brown-Schmidt, Sarah; Duff, Melissa C.

2018-01-01

Converging evidence points to a role for the hippocampus in statistical learning, but open questions about its necessity remain. Evidence for necessity comes from Schapiro and colleagues who report that a single patient with damage to hippocampus and broader medial temporal lobe cortex was unable to discriminate new from old sequences in several statistical learning tasks. The aim of the current study was to replicate these methods in a larger group of patients who have either damage localized to hippocampus or a broader medial temporal lobe damage, to ascertain the necessity of the hippocampus in statistical learning. Patients with hippocampal damage consistently showed less learning overall compared with healthy comparison participants, consistent with an emerging consensus for hippocampal contributions to statistical learning. Interestingly, lesion size did not reliably predict performance. However, patients with hippocampal damage were not uniformly at chance and demonstrated above-chance performance in some task variants. These results suggest that hippocampus is necessary for statistical learning levels achieved by most healthy comparison participants but significant hippocampal pathology alone does not abolish such learning. PMID:29308986

Sigsearch: a new term for post hoc unplanned search for statistically significant relationships with the intent to create publishable findings.

PubMed

Hashim, Muhammad Jawad

2010-09-01

Post-hoc secondary data analysis with no prespecified hypotheses has been discouraged by textbook authors and journal editors alike. Unfortunately no single term describes this phenomenon succinctly. I would like to coin the term "sigsearch" to define this practice and bring it within the teaching lexicon of statistics courses. Sigsearch would include any unplanned, post-hoc search for statistical significance using multiple comparisons of subgroups. It would also include data analysis with outcomes other than the prespecified primary outcome measure of a study as well as secondary data analyses of earlier research.

Attitudes and Achievement in Introductory Psychological Statistics Classes: Traditional versus Computer-Supported Instruction.

ERIC Educational Resources Information Center

Gratz, Zandra S.; And Others

A study was conducted at a large, state-supported college in the Northeast to establish a mechanism by which a popular software package, Statistical Package for the Social Sciences (SPSS), could be used in psychology program statistics courses in such a way that no prior computer expertise would be needed on the part of the faculty or the…

The role of planning skills in the income-achievement gap.

PubMed

Crook, Stephen R; Evans, Gary W

2014-01-01

The pervasive income-achievement gap has been attributed in part to deficiencies in executive functioning (EF). The development of EF is related to children's planning ability, an aspect of development that has received little attention. Longitudinal data from the National Institute of Child Health and Human Development study of early child care show that early childhood poverty (1 and 24 months) is significantly related to fifth grade, math, and reading achievement (n = 1,009). The ability to plan in Grade 3, indexed by the Tower of Hanoi task, mediates the income-achievement gap in math and to a lesser extent in reading. IQ was incorporated as a statistical control throughout. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.

The effect of teacher quality on the achievement of students in Integrated Physics and Chemistry

NASA Astrophysics Data System (ADS)

Alexander, Rima

, utilizing SPSS version 12.0.1 software. Next a test of statistical significance was done to determine whether the null hypothesis could be rejected; and whether or not the research hypothesis could be accepted. Since this is a causal comparative design with only two groups in which student achievement was measured by a test that will yield raw scores, a Chi Square was conducted to determine whether the pass rates of the two groups of students based on obtained and expected percentages were statistically significantly different A Chi Square value of 4.29 was obtained, which indicates that the pass rate for students of highly-qualified teachers was statistically significantly higher than for students of less-qualified teachers. For the purpose of this study a criterion value of (p<.05) was used.

Comparison of the effect of multiple intelligence pedagogy and traditional pedagogy on grade 5 students' achievement and attitudes towards science

NASA Astrophysics Data System (ADS)

Mussen, Kimberly S.

This quantitative research study evaluated the effectiveness of employing pedagogy based on the theory of multiple intelligences (MI). Currently, not all students are performing at the rate mandated by the government. When schools do not meet the required state standards, the school is labeled as not achieving adequate yearly progress (AYP), which may lead to the loss of funding. Any school not achieving AYP would be interested in this study. Due to low state standardized test scores in the district for science, student achievement and attitudes towards learning science were evaluated on a pretest, posttest, essay question, and one attitudinal survey. Statistical significance existed on one of the four research questions. Utilizing the Analysis of Covariance (ANCOVA) for data analysis, student attitudes towards learning science were statically significant in the MI (experimental) group. No statistical significance was found in student achievement on the posttest, delayed posttest, or the essay question test. Social change can result from this study because studying the effects of the multiple intelligence theory incorporated into classroom instruction can have significant effect on how children learn, allowing them to compete in a knowledge society.

Student academic achievement in college chemistry

NASA Astrophysics Data System (ADS)

Tabibzadeh, Kiana S.

General Chemistry is required for variety of baccalaureate degrees, including all medical related fields, engineering, and science majors. Depending on the institution, the prerequisite requirement for college level General Chemistry varies. The success rate for this course is low. The purpose of this study is to examine the factors influencing student academic achievement and retention in General Chemistry at the college level. In this study student achievement is defined by those students who earned grades of "C" or better. The dissertation contains in-depth studies on influence of Intermediate Algebra as a prerequisite compared to Fundamental Chemistry for student academic achievement and student retention in college General Chemistry. In addition the study examined the extent and manner in which student self-efficacy influences student academic achievement in college level General Chemistry. The sample for this part of the study is 144 students enrolled in first semester college level General Chemistry. Student surveys determined student self-efficacy level. The statistical analyses of study demonstrated that Fundamental Chemistry is a better prerequisite for student academic achievement and student retention. The study also found that student self-efficacy has no influence on student academic achievement. The significance of this study will be to provide data for the purpose of establishing a uniform and most suitable prerequisite for college level General Chemistry. Finally the variables identified to influence student academic achievement and enhance student retention will support educators' mission to maximize the students' ability to complete their educational goal at institutions of higher education.

Efforts to improve international migration statistics: a historical perspective.

PubMed

Kraly, E P; Gnanasekaran, K S

1987-01-01

During the past decade, the international statistical community has made several efforts to develop standards for the definition, collection and publication of statistics on international migration. This article surveys the history of official initiatives to standardize international migration statistics by reviewing the recommendations of the International Statistical Institute, International Labor Organization, and the UN, and reports a recently proposed agenda for moving toward comparability among national statistical systems. Heightening awareness of the benefits of exchange and creating motivation to implement international standards requires a 3-pronged effort from the international statistical community. 1st, it is essential to continue discussion about the significance of improvement, specifically standardization, of international migration statistics. The move from theory to practice in this area requires ongoing focus by migration statisticians so that conformity to international standards itself becomes a criterion by which national statistical practices are examined and assessed. 2nd, the countries should be provided with technical documentation to support and facilitate the implementation of the recommended statistical systems. Documentation should be developed with an understanding that conformity to international standards for migration and travel statistics must be achieved within existing national statistical programs. 3rd, the call for statistical research in this area requires more efforts by the community of migration statisticians, beginning with the mobilization of bilateral and multilateral resources to undertake the preceding list of activities.

Scalable detection of statistically significant communities and hierarchies, using message passing for modularity

PubMed Central

Zhang, Pan; Moore, Cristopher

2014-01-01

Modularity is a popular measure of community structure. However, maximizing the modularity can lead to many competing partitions, with almost the same modularity, that are poorly correlated with each other. It can also produce illusory ‘‘communities’’ in random graphs where none exist. We address this problem by using the modularity as a Hamiltonian at finite temperature and using an efficient belief propagation algorithm to obtain the consensus of many partitions with high modularity, rather than looking for a single partition that maximizes it. We show analytically and numerically that the proposed algorithm works all of the way down to the detectability transition in networks generated by the stochastic block model. It also performs well on real-world networks, revealing large communities in some networks where previous work has claimed no communities exist. Finally we show that by applying our algorithm recursively, subdividing communities until no statistically significant subcommunities can be found, we can detect hierarchical structure in real-world networks more efficiently than previous methods. PMID:25489096

The Influence of Ability Grouping on Math Achievement in a Rural Middle School

ERIC Educational Resources Information Center

Pritchard, Robert R.

2012-01-01

The researcher examined the academic performance of low-tracked students (n = 156) using standardized math test scores to determine whether there is a statistically significant difference in achievement depending on academic environment, tracked or nontracked. An analysis of variance (ANOVA) was calculated, using a paired samples t-test for a…

A Study of the Effect of Secondary School Leadership Styles on Student Achievement in Selected Secondary School in Louisiana

ERIC Educational Resources Information Center

Harris, Cydnie Ellen Smith

2012-01-01

The effect of the leadership style of the secondary school principal on student achievement in select public schools in Louisiana was examined in this study. The null hypothesis was that there was no statistically significant difference between principal leadership style and student academic achievement. The researcher submitted the LEAD-Self…

Improving preschoolers' mathematics achievement with tablets: a randomized controlled trial

NASA Astrophysics Data System (ADS)

Schacter, John; Jo, Booil

2017-09-01

With a randomized field experiment of 433 preschoolers, we tested a tablet mathematics program designed to increase young children's mathematics learning. Intervention students played Math Shelf, a comprehensive iPad preschool and year 1 mathematics app, while comparison children received research-based hands-on mathematics instruction delivered by their classroom teachers. After 22 weeks, there was a large and statistically significant effect on mathematics achievement for Math Shelf students (Cohen's d = .94). Moderator analyses demonstrated an even larger effect for low achieving children (Cohen's d = 1.27). These results suggest that early education teachers can improve their students' mathematics outcomes by integrating experimentally proven tablet software into their daily routines.

Middle school science curriculum design and 8th grade student achievement in Massachusetts public schools

NASA Astrophysics Data System (ADS)

Clifford, Betsey A.

The Massachusetts Department of Elementary and Secondary Education (DESE) released proposed Science and Technology/Engineering standards in 2013 outlining the concepts that should be taught at each grade level. Previously, standards were in grade spans and each district determined the method of implementation. There are two different methods used teaching middle school science: integrated and discipline-based. In the proposed standards, the Massachusetts DESE uses grade-by-grade standards using an integrated approach. It was not known if there is a statistically significant difference in student achievement on the 8th grade science MCAS assessment for students taught with an integrated or discipline-based approach. The results on the 8th grade science MCAS test from six public school districts from 2010 -- 2013 were collected and analyzed. The methodology used was quantitative. Results of an ANOVA showed that there was no statistically significant difference in overall student achievement between the two curriculum models. Furthermore, there was no statistically significant difference for the various domains: Earth and Space Science, Life Science, Physical Science, and Technology/Engineering. This information is useful for districts hesitant to make the change from a discipline-based approach to an integrated approach. More research should be conducted on this topic with a larger sample size to better support the results.

Efficacy of Exclusive Lingual Nerve Block versus Conventional Inferior Alveolar Nerve Block in Achieving Lingual Soft-tissue Anesthesia.

PubMed

Balasubramanian, Sasikala; Paneerselvam, Elavenil; Guruprasad, T; Pathumai, M; Abraham, Simin; Krishnakumar Raja, V B

2017-01-01

The aim of this randomized clinical trial was to assess the efficacy of exclusive lingual nerve block (LNB) in achieving selective lingual soft-tissue anesthesia in comparison with conventional inferior alveolar nerve block (IANB). A total of 200 patients indicated for the extraction of lower premolars were recruited for the study. The samples were allocated by randomization into control and study groups. Lingual soft-tissue anesthesia was achieved by IANB and exclusive LNB in the control and study group, respectively. The primary outcome variable studied was anesthesia of ipsilateral lingual mucoperiosteum, floor of mouth and tongue. The secondary variables assessed were (1) taste sensation immediately following administration of local anesthesia and (2) mouth opening and lingual nerve paresthesia on the first postoperative day. Data analysis for descriptive and inferential statistics was performed using SPSS (IBM SPSS Statistics for Windows, Version 22.0, Armonk, NY: IBM Corp. Released 2013) and a P < 0.05 was considered statistically significant. In comparison with the control group, the study group (LNB) showed statistically significant anesthesia of the lingual gingiva of incisors, molars, anterior floor of the mouth, and anterior tongue. Exclusive LNB is superior to IAN nerve block in achieving selective anesthesia of lingual soft tissues. It is technically simple and associated with minimal complications as compared to IAN block.

Efficacy of Exclusive Lingual Nerve Block versus Conventional Inferior Alveolar Nerve Block in Achieving Lingual Soft-tissue Anesthesia

PubMed Central

Balasubramanian, Sasikala; Paneerselvam, Elavenil; Guruprasad, T; Pathumai, M; Abraham, Simin; Krishnakumar Raja, V. B.

2017-01-01

Objective: The aim of this randomized clinical trial was to assess the efficacy of exclusive lingual nerve block (LNB) in achieving selective lingual soft-tissue anesthesia in comparison with conventional inferior alveolar nerve block (IANB). Materials and Methods: A total of 200 patients indicated for the extraction of lower premolars were recruited for the study. The samples were allocated by randomization into control and study groups. Lingual soft-tissue anesthesia was achieved by IANB and exclusive LNB in the control and study group, respectively. The primary outcome variable studied was anesthesia of ipsilateral lingual mucoperiosteum, floor of mouth and tongue. The secondary variables assessed were (1) taste sensation immediately following administration of local anesthesia and (2) mouth opening and lingual nerve paresthesia on the first postoperative day. Results: Data analysis for descriptive and inferential statistics was performed using SPSS (IBM SPSS Statistics for Windows, Version 22.0, Armonk, NY: IBM Corp. Released 2013) and a P < 0.05 was considered statistically significant. In comparison with the control group, the study group (LNB) showed statistically significant anesthesia of the lingual gingiva of incisors, molars, anterior floor of the mouth, and anterior tongue. Conclusion: Exclusive LNB is superior to IAN nerve block in achieving selective anesthesia of lingual soft tissues. It is technically simple and associated with minimal complications as compared to IAN block. PMID:29264294

Barriers to Blacks' Educational Achievement in Higher Education: A Statistical and Conceptual Review.

ERIC Educational Resources Information Center

Lang, Marvel

1992-01-01

Examines trends in the educational achievement of African Americans at secondary and postsecondary levels using data from various national surveys. Barriers to educational achievement are described, and intervention strategies for improving African-American success in higher education are reviewed. Increasing minority participation will require…

The effect of inclusion classrooms on the science achievement of general education students

NASA Astrophysics Data System (ADS)

Dodd, Matthew Robert

General education and Special Education students from three high schools in Rutherford County were sampled to determine the effect on their academic achievement on the Tennessee Biology I Gateway Exam in Inclusion classrooms. Each student's predicted and actual Gateway Exam scores from the academic year 2006--2007 were used to determine the effect the student's classroom had on his academic achievement. Independent variables used in the study were gender, ethnicity, socioeconomic level, grade point average, type of classroom (general or Inclusion), and type student (General Education or Special Education). The statistical tests used in this study were a t-test and a Mann--Whitney U Test. From this study, the effect of the Inclusion classroom on general education students was not significant statistically. Although the Inclusion classroom allows the special education student to succeed in the classroom, the effect on general education students is negligible. This study also provided statistical data that the Inclusion classroom did not improve the special education students' academic performances on the Gateway Exam. Students in a general education classroom with a GPA above 3.000 and those from a household without a low socioeconomic status performed at a statistically different level in this study.

Precollege science achievement growth: Racial-ethnic and gender differences in cognitive and psychosocial constructs

NASA Astrophysics Data System (ADS)

Muller, Patricia Ann

The purpose of this study was to gain a more complete understanding of the differences in science, mathematics and engineering education among racial-ethnic and gender subgroups by exploring factors related to precollege science achievement growth rates. Using Hierarchical Linear Modeling (HLM) and multi-wave, longitudinal data from the first three waves of the National Education Longitudinal Study of 1988--1994 (NELS:88/94), this study examined precollege science achievement growth rates during the 8th to 10th grade period and the 10th to 12th grade period for African American males, African American females, Latino males, Latina females, Asian American males, Asian American females, White males and White females. For the 8th--10th grade period, previous grades were significantly and positively related to science achievement growth for all subgroups; and socio-economic status and high school program were significantly and positively related to science achievement growth for all subgroups except one (Latino males, and Asian American males respectively). For the 10th--12th grade period, the quantity of science courses completed (science units) was the only variable that was statistically significant for more than one racial-ethnic by gender subgroup. Science units taken were significantly and positively related to 10 th--12th grade growth rates for all racial-ethnic by gender subgroups except Latino males. Locus-of-control was the only cognitive or psychosocial factor included from Eccles, Adler, Futterman, Goff, Kaczala, Meece and Midgley's (1983) theoretical framework for achievement behaviors that appeared to exhibit any pattern across race-ethnicities. Locus-of-control was positively related to 8th--10 th grade science achievement growth for females across all racial-ethnic subgroups, as well as for African American males. However, for both the 8 th--10th grade and 10th--12 th grade periods, there was no consistency across racial-ethnic or gender subgroups in

Career Preparedness and School Achievement of Portuguese Children: Longitudinal Trend Articulations

PubMed Central

Oliveira, Íris M.; Taveira, Maria do Céu; Porfeli, Erik J.

2017-01-01

Social Cognitive Career Theory suggests that students' preparedness for the school-to-work transition is a developmental process. Middle school children explore various careers, obtain feedback about their academic progress, and develop career self-efficacy and outcome expectations. These processes advance provisional educational/occupational goals. The literature has suggested articulations between career and academic development and how both vary across demographic characteristics, but longitudinal studies linking these processes are scarce. This study tested articulations between career preparedness and academic achievement during middle school years and employed gender and geographical location as potential moderators affecting the linkage between career and school domains. Participants included 429 children (47.8% girls) from northern (69.5%) and central Portugal (30.5%) followed across four occasions of measurement (MageWave1 = 10.23, SD = 0.50). Data was collected with school records, the Multidimensional Scales of Perceived Self-Efficacy, Career Exploratory Outcome Expectations Scale, Childhood Career Exploration Inventory and Childhood Career Development Scale. Average and orthnormalized linear, quadratic and cubic trends were computed. Pearson correlation coefficients suggested positive and statistically significant associations between career exploratory outcome expectations and academic achievement average trends. Career planning and self-efficacy expectations were negatively associated with academic achievement quadratic trends. Multiple linear regression models suggested that career exploratory outcome expectations and career planning were respectively statistically significant predictors of the average and quadratic trends of academic achievement. Gender moderated the association between the career variables and academic achievement linear trends as well as the relation of career planning and self-efficacy with academic achievement cubic trends

Career Preparedness and School Achievement of Portuguese Children: Longitudinal Trend Articulations.

PubMed

Oliveira, Íris M; Taveira, Maria do Céu; Porfeli, Erik J

2017-01-01

Social Cognitive Career Theory suggests that students' preparedness for the school-to-work transition is a developmental process. Middle school children explore various careers, obtain feedback about their academic progress, and develop career self-efficacy and outcome expectations. These processes advance provisional educational/occupational goals. The literature has suggested articulations between career and academic development and how both vary across demographic characteristics, but longitudinal studies linking these processes are scarce. This study tested articulations between career preparedness and academic achievement during middle school years and employed gender and geographical location as potential moderators affecting the linkage between career and school domains. Participants included 429 children (47.8% girls) from northern (69.5%) and central Portugal (30.5%) followed across four occasions of measurement ( M ageWave1 = 10.23, SD = 0.50). Data was collected with school records, the Multidimensional Scales of Perceived Self-Efficacy, Career Exploratory Outcome Expectations Scale, Childhood Career Exploration Inventory and Childhood Career Development Scale. Average and orthnormalized linear, quadratic and cubic trends were computed. Pearson correlation coefficients suggested positive and statistically significant associations between career exploratory outcome expectations and academic achievement average trends. Career planning and self-efficacy expectations were negatively associated with academic achievement quadratic trends. Multiple linear regression models suggested that career exploratory outcome expectations and career planning were respectively statistically significant predictors of the average and quadratic trends of academic achievement. Gender moderated the association between the career variables and academic achievement linear trends as well as the relation of career planning and self-efficacy with academic achievement cubic trends

The effect on prospective teachers of the learning environment supported by dynamic statistics software

NASA Astrophysics Data System (ADS)

Koparan, Timur

2016-02-01

In this study, the effect on the achievement and attitudes of prospective teachers is examined. With this aim ahead, achievement test, attitude scale for statistics and interviews were used as data collection tools. The achievement test comprises 8 problems based on statistical data, and the attitude scale comprises 13 Likert-type items. The study was carried out in 2014-2015 academic year fall semester at a university in Turkey. The study, which employed the pre-test-post-test control group design of quasi-experimental research method, was carried out on a group of 80 prospective teachers, 40 in the control group and 40 in the experimental group. Both groups had four-hour classes about descriptive statistics. The classes with the control group were carried out through traditional methods while dynamic statistics software was used in the experimental group. Five prospective teachers from the experimental group were interviewed clinically after the application for a deeper examination of their views about application. Qualitative data gained are presented under various themes. At the end of the study, it was found that there is a significant difference in favour of the experimental group in terms of achievement and attitudes, the prospective teachers have affirmative approach to the use of dynamic software and see it as an effective tool to enrich maths classes. In accordance with the findings of the study, it is suggested that dynamic software, which offers unique opportunities, be used in classes by teachers and students.

Relationship between the learning style preferences of medical students and academic achievement

PubMed Central

Almigbal, Turky H.

2015-01-01

Objectives: To investigate the relationship between the learning style preferences of Saudi medical students and their academic achievements. Methods: A cross-sectional study was conducted among 600 medical students at King Saud University in Riyadh, Kingdom of Saudi Arabia from October 2012 to July 2013. The Visual, Aural, Read/Write, and Kinesthetic questionnaire (VARK) questionnaire was used to categorize learning style preferences. Descriptive and analytical statistics were used to identify the learning style preferences of medical students and their relationship to academic achievement, gender, marital status, residency, different teaching curricula, and study resources (for example, teachers’ PowerPoint slides, textbooks, and journals). Results: The results indicated that 261 students (43%) preferred to learn using all VARK modalities. There was a significant difference in learning style preferences between genders (p=0.028). The relationship between learning style preferences and students in different teaching curricula was also statistically significant (p=0.047). However, learning style preferences are not related to a student’s academic achievements, marital status, residency, or study resources (for example, teachers’ PowerPoint slides, textbooks, and journals). Also, after being adjusted to other studies’ variables, the learning style preferences were not related to GPA. Conclusion: Our findings can be used to improve the quality of teaching in Saudi Arabia; students would be advantaged if teachers understood the factors that can be related to students’ learning styles. PMID:25737179

Relationship between the learning style preferences of medical students and academic achievement.

PubMed

Almigbal, Turky H

2015-03-01

To investigate the relationship between the learning style preferences of Saudi medical students and their academic achievements. A cross-sectional study was conducted among 600 medical students at King Saud University in Riyadh, Kingdom of Saudi Arabia from October 2012 to July 2013. The Visual, Aural, Read/Write, and Kinesthetic questionnaire (VARK) questionnaire was used to categorize learning style preferences. Descriptive and analytical statistics were used to identify the learning style preferences of medical students and their relationship to academic achievement, gender, marital status, residency, different teaching curricula, and study resources (for example, teachers' PowerPoint slides, textbooks, and journals). The results indicated that 261 students (43%) preferred to learn using all VARK modalities. There was a significant difference in learning style preferences between genders (p=0.028). The relationship between learning style preferences and students in different teaching curricula was also statistically significant (p=0.047). However, learning style preferences are not related to a student's academic achievements, marital status, residency, or study resources (for example, teachers' PowerPoint slides, textbooks, and journals). Also, after being adjusted to other studies' variables, the learning style preferences were not related to GPA. Our findings can be used to improve the quality of teaching in Saudi Arabia; students would be advantaged if teachers understood the factors that can be related to students' learning styles.

Influence of science and technology magnet middle schools on students' motivation and achievement in science

NASA Astrophysics Data System (ADS)

Allen, David

Some informal discussions among educators regarding motivation of students and academic performance have included the topic of magnet schools. The premise is that a focused theme, such as an aspect of science, positively affects student motivation and academic achievement. However, there is limited research involving magnet schools and their influence on student motivation and academic performance. This study provides empirical data for the discussion about magnet schools influence on motivation and academic ability. This study utilized path analysis in a structural equation modeling framework to simultaneously investigate the relationships between demographic exogenous independent variables, the independent variable of attending a science or technology magnet middle school, and the dependent variables of motivation to learn science and academic achievement in science. Due to the categorical nature of the variables, Bayesian statistical analysis was used to calculate the path coefficients and the standardized effects for each relationship in the model. The coefficients of determination were calculated to determine the amount of variance each path explained. Only five of 21 paths had statistical significance. Only one of the five statistically significant paths (Attended Magnet School to Motivation to Learn Science) explained a noteworthy amount (45.8%) of the variance.

CorSig: a general framework for estimating statistical significance of correlation and its application to gene co-expression analysis.

PubMed

Wang, Hong-Qiang; Tsai, Chung-Jui

2013-01-01

With the rapid increase of omics data, correlation analysis has become an indispensable tool for inferring meaningful associations from a large number of observations. Pearson correlation coefficient (PCC) and its variants are widely used for such purposes. However, it remains challenging to test whether an observed association is reliable both statistically and biologically. We present here a new method, CorSig, for statistical inference of correlation significance. CorSig is based on a biology-informed null hypothesis, i.e., testing whether the true PCC (ρ) between two variables is statistically larger than a user-specified PCC cutoff (τ), as opposed to the simple null hypothesis of ρ = 0 in existing methods, i.e., testing whether an association can be declared without a threshold. CorSig incorporates Fisher's Z transformation of the observed PCC (r), which facilitates use of standard techniques for p-value computation and multiple testing corrections. We compared CorSig against two methods: one uses a minimum PCC cutoff while the other (Zhu's procedure) controls correlation strength and statistical significance in two discrete steps. CorSig consistently outperformed these methods in various simulation data scenarios by balancing between false positives and false negatives. When tested on real-world Populus microarray data, CorSig effectively identified co-expressed genes in the flavonoid pathway, and discriminated between closely related gene family members for their differential association with flavonoid and lignin pathways. The p-values obtained by CorSig can be used as a stand-alone parameter for stratification of co-expressed genes according to their correlation strength in lieu of an arbitrary cutoff. CorSig requires one single tunable parameter, and can be readily extended to other correlation measures. Thus, CorSig should be useful for a wide range of applications, particularly for network analysis of high-dimensional genomic data. A web server for

Developing Statistical Literacy in the Final School Year

ERIC Educational Resources Information Center

Budgett, Stephanie; Rose, Drusilla

2017-01-01

Statistical information pervades everyday life in the twenty-first century. Research shows, however, that the skills needed to be able to understand and critically evaluate statistical information must be specifically taught. In 2013, an externally assessed National Certificate in Educational Achievement standard in statistical literacy was…

First-Year Students' Employment, Engagement, and Academic Achievement: Untangling the Relationship between Work and Grades

ERIC Educational Resources Information Center

Pike, Gary R.; Kuh, George D.; Massa-McKinley, Ryan C.

2008-01-01

This study examined the relationships among first-year students' employment, engagement, and academic achievement using data from the 2004 National Survey of Student Engagement. A statistically significant negative relationship was found between working more than 20 hours per week and grades, even after controlling for students' characteristics…

Supporting Kindergarten Teachers' Mathematics Instruction and Student Achievement through a Curriculum-Based Professional Development Program

ERIC Educational Resources Information Center

Polly, Drew; Wang, Chuang; Lambert, Richard; Martin, Christie; McGee, Jennifer Richardson; Pugalee, David; Lehew, Amy

2017-01-01

This study investigates the impacts of a year-long professional development program on Kindergarten teachers' beliefs and practices and the association of these changes with student achievement in mathematics measured by curriculum-based instruments. Although teacher content knowledge was not statistically significantly different before and after…

Incorporating E-Mail into the Learning Process: Its Impact on Student Academic Achievement and Attitudes.

ERIC Educational Resources Information Center

Yu, Fu-Yun; Yu, Hsin-Jin Jessy

2002-01-01

Describes a study of Taiwan university students that investigated the impacts of incorporating email into the classroom on student achievement and attitudes using a posttest-only control-group design. Results showed a statistically significant difference in academic performance but not in student attitudes toward computers. (Author/LRW)

The Longitudinal Effect of Traumatic Stress and Attachment Difficulties on Academic Achievement for Young Children

ERIC Educational Resources Information Center

Wolfgang, Jeff Drayton

2013-01-01

National educational achievement statistics show that academic underachievement is a significant problem for all students in the United States and for culturally diverse students in particular. The relationship of attachment and its interaction with traumatic stress has been proposed as an alternative explanation for the persistent…

Analysis of statistical misconception in terms of statistical reasoning

NASA Astrophysics Data System (ADS)

Maryati, I.; Priatna, N.

2018-05-01

Reasoning skill is needed for everyone to face globalization era, because every person have to be able to manage and use information from all over the world which can be obtained easily. Statistical reasoning skill is the ability to collect, group, process, interpret, and draw conclusion of information. Developing this skill can be done through various levels of education. However, the skill is low because many people assume that statistics is just the ability to count and using formulas and so do students. Students still have negative attitude toward course which is related to research. The purpose of this research is analyzing students’ misconception in descriptive statistic course toward the statistical reasoning skill. The observation was done by analyzing the misconception test result and statistical reasoning skill test; observing the students’ misconception effect toward statistical reasoning skill. The sample of this research was 32 students of math education department who had taken descriptive statistic course. The mean value of misconception test was 49,7 and standard deviation was 10,6 whereas the mean value of statistical reasoning skill test was 51,8 and standard deviation was 8,5. If the minimal value is 65 to state the standard achievement of a course competence, students’ mean value is lower than the standard competence. The result of students’ misconception study emphasized on which sub discussion that should be considered. Based on the assessment result, it was found that students’ misconception happen on this: 1) writing mathematical sentence and symbol well, 2) understanding basic definitions, 3) determining concept that will be used in solving problem. In statistical reasoning skill, the assessment was done to measure reasoning from: 1) data, 2) representation, 3) statistic format, 4) probability, 5) sample, and 6) association.

A SIGNIFICANCE TEST FOR THE LASSO1

PubMed Central

Lockhart, Richard; Taylor, Jonathan; Tibshirani, Ryan J.; Tibshirani, Robert

2014-01-01

In the sparse linear regression setting, we consider testing the significance of the predictor variable that enters the current lasso model, in the sequence of models visited along the lasso solution path. We propose a simple test statistic based on lasso fitted values, called the covariance test statistic, and show that when the true model is linear, this statistic has an Exp(1) asymptotic distribution under the null hypothesis (the null being that all truly active variables are contained in the current lasso model). Our proof of this result for the special case of the first predictor to enter the model (i.e., testing for a single significant predictor variable against the global null) requires only weak assumptions on the predictor matrix X. On the other hand, our proof for a general step in the lasso path places further technical assumptions on X and the generative model, but still allows for the important high-dimensional case p > n, and does not necessarily require that the current lasso model achieves perfect recovery of the truly active variables. Of course, for testing the significance of an additional variable between two nested linear models, one typically uses the chi-squared test, comparing the drop in residual sum of squares (RSS) to a χ12 distribution. But when this additional variable is not fixed, and has been chosen adaptively or greedily, this test is no longer appropriate: adaptivity makes the drop in RSS stochastically much larger than χ12 under the null hypothesis. Our analysis explicitly accounts for adaptivity, as it must, since the lasso builds an adaptive sequence of linear models as the tuning parameter λ decreases. In this analysis, shrinkage plays a key role: though additional variables are chosen adaptively, the coefficients of lasso active variables are shrunken due to the l1 penalty. Therefore, the test statistic (which is based on lasso fitted values) is in a sense balanced by these two opposing properties—adaptivity and

Searching for statistically significant regulatory modules.

PubMed

Bailey, Timothy L; Noble, William Stafford

2003-10-01

The regulatory machinery controlling gene expression is complex, frequently requiring multiple, simultaneous DNA-protein interactions. The rate at which a gene is transcribed may depend upon the presence or absence of a collection of transcription factors bound to the DNA near the gene. Locating transcription factor binding sites in genomic DNA is difficult because the individual sites are small and tend to occur frequently by chance. True binding sites may be identified by their tendency to occur in clusters, sometimes known as regulatory modules. We describe an algorithm for detecting occurrences of regulatory modules in genomic DNA. The algorithm, called mcast, takes as input a DNA database and a collection of binding site motifs that are known to operate in concert. mcast uses a motif-based hidden Markov model with several novel features. The model incorporates motif-specific p-values, thereby allowing scores from motifs of different widths and specificities to be compared directly. The p-value scoring also allows mcast to only accept motif occurrences with significance below a user-specified threshold, while still assigning better scores to motif occurrences with lower p-values. mcast can search long DNA sequences, modeling length distributions between motifs within a regulatory module, but ignoring length distributions between modules. The algorithm produces a list of predicted regulatory modules, ranked by E-value. We validate the algorithm using simulated data as well as real data sets from fruitfly and human. http://meme.sdsc.edu/MCAST/paper

Statistical trend analysis and extreme distribution of significant wave height from 1958 to 1999 - an application to the Italian Seas

NASA Astrophysics Data System (ADS)

Martucci, G.; Carniel, S.; Chiggiato, J.; Sclavo, M.; Lionello, P.; Galati, M. B.

2009-09-01

The study is a statistical analysis of sea states timeseries derived using the wave model WAM forced by the ERA-40 dataset in selected areas near the Italian coasts. For the period 1 January 1958 to 31 December 1999 the analysis yields: (i) the existence of a negative trend in the annual- and winter-averaged sea state heights; (ii) the existence of a turning-point in late 70's in the annual-averaged trend of sea state heights at a site in the Northern Adriatic Sea; (iii) the overall absence of a significant trend in the annual-averaged mean durations of sea states over thresholds; (iv) the assessment of the extreme values on a time-scale of thousand years. The analysis uses two methods to obtain samples of extremes from the independent sea states: the r-largest annual maxima and the peak-over-threshold. The two methods show statistical differences in retrieving the return values and more generally in describing the significant wave field. The study shows the existence of decadal negative trends in the significant wave heights and by this it conveys useful information on the wave climatology of the Italian seas during the second half of the 20th century.

The effects of hands-on-science instruction on the science achievement of middle school students

NASA Astrophysics Data System (ADS)

Wiggins, Felita

Student achievement in the Twenty First Century demands a new rigor in student science knowledge, since advances in science and technology require students to think and act like scientists. As a result, students must acquire proficient levels of knowledge and skills to support a knowledge base that is expanding exponentially with new scientific advances. This study examined the effects of hands-on-science instruction on the science achievement of middle school students. More specifically, this study was concerned with the influence of hands-on science instruction versus traditional science instruction on the science test scores of middle school students. The subjects in this study were one hundred and twenty sixth-grade students in six classes. Instruction involved lecture/discussion and hands-on activities carried out for a three week period. Specifically, the study ascertained the influence of the variables gender, ethnicity, and socioeconomic status on the science test scores of middle school students. Additionally, this study assessed the effect of the variables gender, ethnicity, and socioeconomic status on the attitudes of sixth grade students toward science. The two instruments used to collect data for this study were the Prentice Hall unit ecosystem test and the Scientific Work Experience Programs for Teachers Study (SWEPT) student's attitude survey. Moreover, the data for the study was treated using the One-Way Analysis of Covariance and the One-Way Analysis of Variance. The following findings were made based on the results: (1) A statistically significant difference existed in the science performance of middle school students exposed to hands-on science instruction. These students had significantly higher scores than the science performance of middle school students exposed to traditional instruction. (2) A statistically significant difference did not exist between the science scores of male and female middle school students. (3) A statistically

Manganese exposure from drinking water and children's academic achievement.

PubMed

Khan, Khalid; Wasserman, Gail A; Liu, Xinhua; Ahmed, Ershad; Parvez, Faruque; Slavkovich, Vesna; Levy, Diane; Mey, Jacob; van Geen, Alexander; Graziano, Joseph H; Factor-Litvak, Pam

2012-01-01

Drinking water manganese (WMn) is a potential threat to children's health due to its associations with a wide range of outcomes including cognitive, behavioral and neuropsychological effects. Although adverse effects of Mn on cognitive function of the children indicate possible impact on their academic achievement little evidence on this issue is available. Moreover, little is known regarding potential interactions between exposure to Mn and other metals, especially water arsenic (WAs). In Araihazar, a rural area of Bangladesh, we conducted a cross-sectional study of 840 children to investigate associations between WMn and WAs and academic achievement in mathematics and languages among elementary school-children, aged 8-11 years. Data on As and Mn exposure were collected from the participants at the baseline of an ongoing longitudinal study of school-based educational intervention. Annual scores of the study children in languages (Bangla and English) and mathematics were obtained from the academic achievement records of the elementary schools. WMn above the WHO standard of 400μg/L was associated with 6.4% score loss (95% CI=-12.3 to -0.5) in mathematics achievement test scores, adjusted for WAs and other sociodemographic variables. We did not find any statistically significant associations between WMn and academic achievement in either language. Neither WAs nor urinary As was significantly related to any of the three academic achievement scores. Our finding suggests that a large number of children in rural Bangladesh may experience deficits in mathematics due to high concentrations of Mn exposure in drinking water. Copyright © 2011 Elsevier Inc. All rights reserved.

Cultural invariance of goal orientation and self-efficacy in New Zealand: Relations with achievement.

PubMed

Meissel, Kane; Rubie-Davies, Christine M

2016-03-01

There is substantial evidence indicating that various psychological processes are affected by cultural context, but such research is comparatively nascent within New Zealand. As there are four large cultural groups in New Zealand, representing an intersection of individualist, collectivist, indigenous, colonial, and immigrant cultures, New Zealand is an important context in which to investigate the role of culture in such processes. This study investigated goal orientation and self-efficacy beliefs among students of different cultural backgrounds in New Zealand, associations between motivational beliefs and achievement, and whether any relations differed by cultural background. Participants were 2,210 students attending three intermediate schools. Participants responded to a questionnaire at the beginning of the school year to evaluate self-efficacy for mathematics and mastery and performance goal orientation. Participants also completed a standardized mathematics achievement test at the beginning and end of the year. The factor structure was sufficiently invariant by cultural group, but with statistically significant differences in average level of endorsement. Self-efficacy for mathematics predicted marginally higher end-of-year achievement after controlling for beginning-of-year achievement, with a stronger relationship for Māori and Pasifika, but no statistically significant relationship with achievement among Asian students. The questionnaire used was a valid instrument for the four main cultural groups in New Zealand. Differences were found in motivation levels, and Māori and Pasifika were more affected by their self-reported self-efficacy. Teachers may be able to raise students' self-beliefs by conveying high expectations for these students, potentially supporting higher academic outcomes. © 2015 The British Psychological Society.

Funding source and primary outcome changes in clinical trials registered on ClinicalTrials.gov are associated with the reporting of a statistically significant primary outcome: a cross-sectional study.

PubMed

Ramagopalan, Sreeram V; Skingsley, Andrew P; Handunnetthi, Lahiru; Magnus, Daniel; Klingel, Michelle; Pakpoor, Julia; Goldacre, Ben

2015-01-01

We and others have shown a significant proportion of interventional trials registered on ClinicalTrials.gov have their primary outcomes altered after the listed study start and completion dates. The objectives of this study were to investigate whether changes made to primary outcomes are associated with the likelihood of reporting a statistically significant primary outcome on ClinicalTrials.gov. A cross-sectional analysis of all interventional clinical trials registered on ClinicalTrials.gov as of 20 November 2014 was performed. The main outcome was any change made to the initially listed primary outcome and the time of the change in relation to the trial start and end date. 13,238 completed interventional trials were registered with ClinicalTrials.gov that also had study results posted on the website. 2555 (19.3%) had one or more statistically significant primary outcomes. Statistical analysis showed that registration year, funding source and primary outcome change after trial completion were associated with reporting a statistically significant primary outcome .  Funding source and primary outcome change after trial completion are associated with a statistically significant primary outcome report on clinicaltrials.gov.

Significant lexical relationships

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pedersen, T.; Kayaalp, M.; Bruce, R.

Statistical NLP inevitably deals with a large number of rare events. As a consequence, NLP data often violates the assumptions implicit in traditional statistical procedures such as significance testing. We describe a significance test, an exact conditional test, that is appropriate for NLP data and can be performed using freely available software. We apply this test to the study of lexical relationships and demonstrate that the results obtained using this test are both theoretically more reliable and different from the results obtained using previously applied tests.

Socioeconomic status, physical fitness, self-concept, attitude toward physical education, and academic achievement of children.

PubMed

Aktop, Abdurrahman

2010-04-01

The goal was to analyze the physical fitness, self-concept, attitudes toward physical education, and academic achievement of Turkish elementary school children by socioeconomic status. 198 (101 boys, 97 girls) students from Grades 7 and 8 completed the Children's Attitude Inventory towards Physical Education, the Piers-Harris Children's Self-concept Scale, and Eurofit Physical Fitness Test Battery. Significant differences were found between the groups of Low and High socioeconomic status (SES) in terms of physical fitness and academic achievement. While the Low SES group had higher mean scores on physical fitness, mean academic achievements of the High SES group were higher. Mean differences in height, self-concept, and children's attitudes toward physical education by socioeconomic status were not statistically significant. Particular attention should be paid to physical fitness in children of high socioeconomic status and the academic achievement of children with low socioeconomic status.

Museum-based learning: Informal learning settings and their role in student motivation and achievement in science

NASA Astrophysics Data System (ADS)

Holmes, Julie Ann

This study examined changes in student motivation and achievement in science in relationship with a visit to the IDEA Place Experiment Gallery. The study was based on the pretest-posttest control comparison group design with four treatment groups: control, exhibit, lesson, and exhibit/lesson. The sample was 228 sixth grade students from a public north central Louisiana school who were randomly assigned to one of the four experimental groups. Pretest, posttest, and delayed posttest measures of intrinsic motivation and achievement in science were determined using the Children's Academic Intrinsic Motivation Inventory and an achievement test written to measure areas of science incorporated in the Experiment Gallery exhibits. The data were analyzed using a one way Analysis of Variance (ANOVA), dependent t tests, and Pearson r. Statistical analysis revealed: (a) no significant differences in motivation or achievement on pretest and posttest scores between groups and, (b) no significant relationships between motivation level and achievement between groups on the posttest. Significant differences were found within groups for (a) the lesson group in motivation, and (b) the exhibit group in achievement from pretest to posttest and from posttest to delayed posttest. A significant relationship between level of motivation and science achievement was revealed for the exhibit group on the delayed posttests. There were no other significant findings to support that the effects of the treatment led to any long term effects on motivation or achievement within any of the four experimental groups.

Weighted Feature Significance: A Simple, Interpretable Model of Compound Toxicity Based on the Statistical Enrichment of Structural Features

PubMed Central

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

WWC Quick Review of the Report "Financial Incentives and Student Achievement: Evidence from Randomized Trials"

ERIC Educational Resources Information Center

What Works Clearinghouse, 2010

2010-01-01

This study examined the effect of financial incentives on student achievement. The study analyzed data on approximately 38,000 students from about 260 public schools in Chicago, Dallas, New York City, and Washington, DC. The study found no statistically significant effects on standardized math or reading outcomes in Chicago, New York City, or…

Basic Mathematics Test Predicts Statistics Achievement and Overall First Year Academic Success

ERIC Educational Resources Information Center

Fonteyne, Lot; De Fruyt, Filip; Dewulf, Nele; Duyck, Wouter; Erauw, Kris; Goeminne, Katy; Lammertyn, Jan; Marchant, Thierry; Moerkerke, Beatrijs; Oosterlinck, Tom; Rosseel, Yves

2015-01-01

In the psychology and educational science programs at Ghent University, only 36.1% of the new incoming students in 2011 and 2012 passed all exams. Despite availability of information, many students underestimate the scientific character of social science programs. Statistics courses are a major obstacle in this matter. Not all enrolling students…

Impact of Integrated Science and English Language Arts Literacy Supplemental Instructional Intervention on Science Academic Achievement of Elementary Students

NASA Astrophysics Data System (ADS)

Marks, Jamar Terry

The purpose of this quasi-experimental, nonequivalent pretest-posttest control group design study was to determine if any differences existed in upper elementary school students' science academic achievement when instructed using an 8-week integrated science and English language arts literacy supplemental instructional intervention in conjunction with traditional science classroom instruction as compared to when instructed using solely traditional science classroom instruction. The targeted sample population consisted of fourth-grade students enrolled in a public elementary school located in the southeastern region of the United States. The convenience sample size consisted of 115 fourth-grade students enrolled in science classes. The pretest and posttest academic achievement data collected consisted of the science segment from the Spring 2015, and Spring 2016 state standardized assessments. Pretest and posttest academic achievement data were analyzed using an ANCOVA statistical procedure to test for differences, and the researcher reported the results of the statistical analysis. The results of the study show no significant difference in science academic achievement between treatment and control groups. An interpretation of the results and recommendations for future research were provided by the researcher upon completion of the statistical analysis.

Effects of the Self-Regulation Empowerment Program (SREP) on middle school students' strategic skills, self-efficacy, and mathematics achievement.

PubMed

Cleary, Timothy J; Velardi, Brittany; Schnaidman, Bracha

2017-10-01

The current study examined the effectiveness of an applied self-regulated learning intervention (Self-Regulation Empowerment Program (SREP)) relative to an existing, school-based remedial mathematics intervention for improving the motivation, strategic skills, and mathematics achievement of academically at-risk middle school students. Although significant group differences in student self-regulated learning (SRL) were not observed when using self-report questionnaires, medium to large and statistically significant group differences were observed across several contextualized, situation-specific measures of strategic and regulatory thinking. The SREP group also exhibited a statistically significant and more positive trend in achievement scores over two years in middle school relative to the comparison condition. Finally, SREP students and coaches reported SREP to be a socially-valid intervention, in terms of acceptability and importance. The importance of this study and critical areas for future research are highlighted and discussed. Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Barnacle geese achieve significant energetic savings by changing posture.

PubMed

Tickle, Peter G; Nudds, Robert L; Codd, Jonathan R

2012-01-01

Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture.

What Works Clearinghouse Quick Review: "KIPP Middle Schools: Impacts on Achievement and Other Outcomes, Final Report"

ERIC Educational Resources Information Center

What Works Clearinghouse, 2013

2013-01-01

This study examined whether attending a Knowledge is Power Program (KIPP) middle school improved students' reading, math, social studies, and science achievement for up to 4 years following enrollment. The study reported that students attending KIPP middle schools scored statistically significantly higher than matched students on all of the state…

Effects of Matching Multiple Memory Strategies with Computer-Assisted Instruction on Students' Statistics Learning Achievement

ERIC Educational Resources Information Center

Liao, Ying; Lin, Wen-He

2016-01-01

In the era when digitalization is pursued, numbers are the major medium of information performance and statistics is the primary instrument to interpret and analyze numerical information. For this reason, the cultivation of fundamental statistical literacy should be a key in the learning area of mathematics at the stage of compulsory education.…

Barnacle Geese Achieve Significant Energetic Savings by Changing Posture

PubMed Central

Tickle, Peter G.; Nudds, Robert L.; Codd, Jonathan R.

2012-01-01

Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture. PMID:23071672

A systematic review and meta-analysis of acute stroke unit care: What’s beyond the statistical significance?

PubMed Central

2013-01-01

Background The benefits of stroke unit care in terms of reducing death, dependency and institutional care were demonstrated in a 2009 Cochrane review carried out by the Stroke Unit Trialists’ Collaboration. Methods As requested by the Belgian health authorities, a systematic review and meta-analysis of the effect of acute stroke units was performed. Clinical trials mentioned in the original Cochrane review were included. In addition, an electronic database search on Medline, Embase, the Cochrane Central Register of Controlled Trials, and Physiotherapy Evidence Database (PEDro) was conducted to identify trials published since 2006. Trials investigating acute stroke units compared to alternative care were eligible for inclusion. Study quality was appraised according to the criteria recommended by Scottish Intercollegiate Guidelines Network (SIGN) and the GRADE system. In the meta-analysis, dichotomous outcomes were estimated by calculating odds ratios (OR) and continuous outcomes were estimated by calculating standardized mean differences. The weight of a study was calculated based on inverse variance. Results Evidence from eight trials comparing acute stroke unit and conventional care (general medical ward) were retained for the main synthesis and analysis. The findings from this study were broadly in line with the original Cochrane review: acute stroke units can improve survival and independency, as well as reduce the chance of hospitalization and the length of inpatient stay. The improvement with stroke unit care on mortality was less conclusive and only reached borderline level of significance (OR 0.84, 95% CI 0.70 to 1.00, P = 0.05). This improvement became statistically non-significant (OR 0.87, 95% CI 0.74 to 1.03, P = 0.12) when data from two unpublished trials (Goteborg-Ostra and Svendborg) were added to the analysis. After further also adding two additional trials (Beijing, Stockholm) with very short observation periods (until discharge), the

Development of inquiry-based learning activities integrated with the local learning resource to promote learning achievement and analytical thinking ability of Mathayomsuksa 3 student

NASA Astrophysics Data System (ADS)

Sukji, Paweena; Wichaidit, Pacharee Rompayom; Wichaidit, Sittichai

2018-01-01

The objectives of this study were to: 1) compare learning achievement and analytical thinking ability of Mathayomsuksa 3 students before and after learning through inquiry-based learning activities integrated with the local learning resource, and 2) compare average post-test score of learning achievement and analytical thinking ability to its cutting score. The target of this study was 23 Mathayomsuksa 3 students who were studying in the second semester of 2016 academic year from Banchatfang School, Chainat Province. Research instruments composed of: 1) 6 lesson plans of Environment and Natural Resources, 2) the learning achievement test, and 3) analytical thinking ability test. The results showed that 1) student' learning achievement and analytical thinking ability after learning were higher than that of before at the level of .05 statistical significance, and 2) average posttest score of student' learning achievement and analytical thinking ability were higher than its cutting score at the level of .05 statistical significance. The implication of this research is for science teachers and curriculum developers to design inquiry activities that relate to student's context.

Sustaining School Achievement in California's Elementary Schools after State Monitoring

ERIC Educational Resources Information Center

McCabe, Molly

2010-01-01

This study examined the Academic Performance Index (API) and Adequate Yearly Progress (AYP) achievement trends between 2004 and 2006 of 58 California public elementary schools after exiting state monitoring and investigated practices for sustaining consistent achievement growth. Statistical methods were used to analyze statewide achievement trends…

Determining coding CpG islands by identifying regions significant for pattern statistics on Markov chains.

PubMed

Singer, Meromit; Engström, Alexander; Schönhuth, Alexander; Pachter, Lior

2011-09-23

Recent experimental and computational work confirms that CpGs can be unmethylated inside coding exons, thereby showing that codons may be subjected to both genomic and epigenomic constraint. It is therefore of interest to identify coding CpG islands (CCGIs) that are regions inside exons enriched for CpGs. The difficulty in identifying such islands is that coding exons exhibit sequence biases determined by codon usage and constraints that must be taken into account. We present a method for finding CCGIs that showcases a novel approach we have developed for identifying regions of interest that are significant (with respect to a Markov chain) for the counts of any pattern. Our method begins with the exact computation of tail probabilities for the number of CpGs in all regions contained in coding exons, and then applies a greedy algorithm for selecting islands from among the regions. We show that the greedy algorithm provably optimizes a biologically motivated criterion for selecting islands while controlling the false discovery rate. We applied this approach to the human genome (hg18) and annotated CpG islands in coding exons. The statistical criterion we apply to evaluating islands reduces the number of false positives in existing annotations, while our approach to defining islands reveals significant numbers of undiscovered CCGIs in coding exons. Many of these appear to be examples of functional epigenetic specialization in coding exons.

The Role of Neighborhood Context and School Climate in School-Level Academic Achievement.

PubMed

Ruiz, Linda D; McMahon, Susan D; Jason, Leonard A

2018-06-01

In recent years, the quality of education available to children has become increasingly dependent on the social and economic demographics of neighborhoods in which the children live. This study assesses the role of community violence in explaining the relation between socio-economic status (SES) and academic outcomes and the potential of positive school climate to promote academic achievement. With a sample of 297 Chicago public elementary schools, we examine community-level and school-level data and use Geographic Information Systems (GIS) mapping to illustrate how school academic achievement coincides with neighborhood economics and crime statistics. Results support the hypothesized mediation, such that lower SES was associated with lower academic achievement, and violent crime partially mediated this relation. School climate was positively associated with academic achievement, and student safety significantly moderated the relation between SES and academic achievement. Implications for theory, research, and intervention are discussed. © Society for Community Research and Action 2018.

Time series, periodograms, and significance

NASA Astrophysics Data System (ADS)

Hernandez, G.

1999-05-01

The geophysical literature shows a wide and conflicting usage of methods employed to extract meaningful information on coherent oscillations from measurements. This makes it difficult, if not impossible, to relate the findings reported by different authors. Therefore, we have undertaken a critical investigation of the tests and methodology used for determining the presence of statistically significant coherent oscillations in periodograms derived from time series. Statistical significance tests are only valid when performed on the independent frequencies present in a measurement. Both the number of possible independent frequencies in a periodogram and the significance tests are determined by the number of degrees of freedom, which is the number of true independent measurements, present in the time series, rather than the number of sample points in the measurement. The number of degrees of freedom is an intrinsic property of the data, and it must be determined from the serial coherence of the time series. As part of this investigation, a detailed study has been performed which clearly illustrates the deleterious effects that the apparently innocent and commonly used processes of filtering, de-trending, and tapering of data have on periodogram analysis and the consequent difficulties in the interpretation of the statistical significance thus derived. For the sake of clarity, a specific example of actual field measurements containing unevenly-spaced measurements, gaps, etc., as well as synthetic examples, have been used to illustrate the periodogram approach, and pitfalls, leading to the (statistical) significance tests for the presence of coherent oscillations. Among the insights of this investigation are: (1) the concept of a time series being (statistically) band limited by its own serial coherence and thus having a critical sampling rate which defines one of the necessary requirements for the proper statistical design of an experiment; (2) the design of a critical

[Achieving an educative strategy in undergraduate medical interns with respect to patients with diabetes].

PubMed

Medina-Figueroa, Alda María; Espinosa-Alarcón, Patricia Atzimba

2007-01-01

To estimate the achievement of an educative strategy that promoted participation of the development of the clinical aptitude of undergraduate medical students with regard to patients with diabetes. We conducted a quasi-experimental study with two groups of undergraduate medical students. We validated an instrument to explore clinical attitude concerning diabetes mellitus (ACDIME) with 30 items for each of six indicators. The instrument was applied at two general hospitals, before and after carrying out the educative strategies. In the experimental group, we conducted an educative strategy that promotes participation in developing clinical aptitude, while the customary strategy was developed in the control group. ACDIME consistency was 0.80. Both study groups were similar before the educative strategies (p = 0.165). Statistically significant differences existed after the strategies in all indicators were evaluated, in favor of the experimental group. The tendency to change, with a criterion of 50% or more, was only statistically significant in the experimental group (p < 0.0001). The ACDIME instrument is valid and reliable. The educative strategy that promoted participation is clearly superior to the customary strategy with regard to achievement.

A study of the attitudes and academic achievement in biology of females in a single-sex school vs. a coeducational school in the Philadelphia Archdiocesan secondary schools

NASA Astrophysics Data System (ADS)

Proach, John Ann

2000-11-01

There is proof that the educational system has conveyed unrealistic role expectations and has neglected to address the changing needs of girls. Children form attitudes about themselves and others based on the communications they get over time from parents, other adults, peers, and a variety of societal influences, including school. This study focused on two groups of tenth-grade high school, female, biology students in the Archdiocese of Philadelphia. The purpose was to compare attitude in science and academic achievement of females in a single-sex vs. a coeducational school. Data collection included three attitudinal surveys: Women in Science, Science Attitude Scale, and Perceptions of Science and Scientists, also the National Association of Biology Teachers/National Science Teachers High School Biology Examination Version B. administered as a pretest and posttest to measure academic achievement. These instruments were used to determine if the differences between attitudes and perceptions toward science and achievement in science were alike for females in a single-sex school and a coeducational school. The study also tested to see if females in a single-sex school would attain greater academic achievement in biology than girls in a coeducational school. The Chi-square statistic was used to analyze data in the three attitudinal surveys. The NABT/NSTA High School Biology Examination determined the students' initial and final competency levels in general biology. The mean science achievement of each of the two groups was tested for statistical significance using the t-test. In the two schools the t-test statistic showed significant difference between the pretest and a slight statistical difference on the posttest; the preferred analysis was an ANCOVA used to compare the posttest scores using the pretest as a covariate. The data implies that attitudes and perceptions are basically the same in both environments with minor differences. Results of these analyses suggest

Windows of achievement for development milestones of Sri Lankan infants and toddlers: estimation through statistical modelling.

PubMed

Thalagala, N

2015-11-01

The normative age ranges during which cohorts of children achieve milestones are called windows of achievement. The patterns of these windows of achievement are known to be both genetically and environmentally dependent. This study aimed to determine the windows of achievement for motor, social emotional, language and cognitive development milestones for infants and toddlers in Sri Lanka. A set of 293 milestones identified through a literature review were subjected to content validation using parent and expert reviews, which resulted in the selection of a revised set of 277 milestones. Thereafter, a sample of 1036 children from 2 months to 30 months was examined to see whether or not they had attained the selected milestones. Percentile ages of attaining milestone were determined using a rearranged closed form equation related to the logistic regression. The parameters required for calculations were derived through the logistic regression of milestone achievement statuses against ages of children. These percentile ages were used to define the respective windows of achievement. A set of 178 robust indicators that represent motor, socio emotional, language and cognitive development skills and their windows of achievement relevant to 2 to 24 months of age were determined. Windows of achievement for six gross motor milestones determined in the study were shown to closely overlap a similar set of windows of achievement published by the World Health Organization indicating the validity of some findings. A methodology combining the content validation based on qualitative techniques and age validation based on regression modelling found to be effective for determining age percentiles for realizing milestones and determining respective windows of achievement. © 2015 John Wiley & Sons Ltd.

Economic Statistical Design of Integrated X-bar-S Control Chart with Preventive Maintenance and General Failure Distribution

PubMed Central

Caballero Morales, Santiago Omar

2013-01-01

The application of Preventive Maintenance (PM) and Statistical Process Control (SPC) are important practices to achieve high product quality, small frequency of failures, and cost reduction in a production process. However there are some points that have not been explored in depth about its joint application. First, most SPC is performed with the X-bar control chart which does not fully consider the variability of the production process. Second, many studies of design of control charts consider just the economic aspect while statistical restrictions must be considered to achieve charts with low probabilities of false detection of failures. Third, the effect of PM on processes with different failure probability distributions has not been studied. Hence, this paper covers these points, presenting the Economic Statistical Design (ESD) of joint X-bar-S control charts with a cost model that integrates PM with general failure distribution. Experiments showed statistically significant reductions in costs when PM is performed on processes with high failure rates and reductions in the sampling frequency of units for testing under SPC. PMID:23527082

Statistical significance approximation in local trend analysis of high-throughput time-series data using the theory of Markov chains.

PubMed

Xia, Li C; Ai, Dongmei; Cram, Jacob A; Liang, Xiaoyi; Fuhrman, Jed A; Sun, Fengzhu

2015-09-21

Local trend (i.e. shape) analysis of time series data reveals co-changing patterns in dynamics of biological systems. However, slow permutation procedures to evaluate the statistical significance of local trend scores have limited its applications to high-throughput time series data analysis, e.g., data from the next generation sequencing technology based studies. By extending the theories for the tail probability of the range of sum of Markovian random variables, we propose formulae for approximating the statistical significance of local trend scores. Using simulations and real data, we show that the approximate p-value is close to that obtained using a large number of permutations (starting at time points >20 with no delay and >30 with delay of at most three time steps) in that the non-zero decimals of the p-values obtained by the approximation and the permutations are mostly the same when the approximate p-value is less than 0.05. In addition, the approximate p-value is slightly larger than that based on permutations making hypothesis testing based on the approximate p-value conservative. The approximation enables efficient calculation of p-values for pairwise local trend analysis, making large scale all-versus-all comparisons possible. We also propose a hybrid approach by integrating the approximation and permutations to obtain accurate p-values for significantly associated pairs. We further demonstrate its use with the analysis of the Polymouth Marine Laboratory (PML) microbial community time series from high-throughput sequencing data and found interesting organism co-occurrence dynamic patterns. The software tool is integrated into the eLSA software package that now provides accelerated local trend and similarity analysis pipelines for time series data. The package is freely available from the eLSA website: http://bitbucket.org/charade/elsa.

The Effect on Prospective Teachers of the Learning Environment Supported by Dynamic Statistics Software

ERIC Educational Resources Information Center

Koparan, Timur

2016-01-01

In this study, the effect on the achievement and attitudes of prospective teachers is examined. With this aim ahead, achievement test, attitude scale for statistics and interviews were used as data collection tools. The achievement test comprises 8 problems based on statistical data, and the attitude scale comprises 13 Likert-type items. The study…

Some Variables in Relation to Students' Anxiety in Learning Statistics.

ERIC Educational Resources Information Center

Sutarso, Toto

The purpose of this study was to investigate some variables that relate to students' anxiety in learning statistics. The variables included sex, class level, students' achievement, school, mathematical background, previous statistics courses, and race. The instrument used was the 24-item Students' Attitudes Toward Statistics (STATS), which was…

Consomic mouse strain selection based on effect size measurement, statistical significance testing and integrated behavioral z-scoring: focus on anxiety-related behavior and locomotion.

PubMed

Labots, M; Laarakker, M C; Ohl, F; van Lith, H A

2016-06-29

Selecting chromosome substitution strains (CSSs, also called consomic strains/lines) used in the search for quantitative trait loci (QTLs) consistently requires the identification of the respective phenotypic trait of interest and is simply based on a significant difference between a consomic and host strain. However, statistical significance as represented by P values does not necessarily predicate practical importance. We therefore propose a method that pays attention to both the statistical significance and the actual size of the observed effect. The present paper extends on this approach and describes in more detail the use of effect size measures (Cohen's d, partial eta squared - η p (2) ) together with the P value as statistical selection parameters for the chromosomal assignment of QTLs influencing anxiety-related behavior and locomotion in laboratory mice. The effect size measures were based on integrated behavioral z-scoring and were calculated in three experiments: (A) a complete consomic male mouse panel with A/J as the donor strain and C57BL/6J as the host strain. This panel, including host and donor strains, was analyzed in the modified Hole Board (mHB). The consomic line with chromosome 19 from A/J (CSS-19A) was selected since it showed increased anxiety-related behavior, but similar locomotion compared to its host. (B) Following experiment A, female CSS-19A mice were compared with their C57BL/6J counterparts; however no significant differences and effect sizes close to zero were found. (C) A different consomic mouse strain (CSS-19PWD), with chromosome 19 from PWD/PhJ transferred on the genetic background of C57BL/6J, was compared with its host strain. Here, in contrast with CSS-19A, there was a decreased overall anxiety in CSS-19PWD compared to C57BL/6J males, but not locomotion. This new method shows an improved way to identify CSSs for QTL analysis for anxiety-related behavior using a combination of statistical significance testing and effect

Assessing the Disconnect between Grade Expectation and Achievement in a Business Statistics Course

ERIC Educational Resources Information Center

Berenson, Mark L.; Ramnarayanan, Renu; Oppenheim, Alan

2015-01-01

In an institutional review board--approved study aimed at evaluating differences in learning between a large-sized introductory business statistics course section using courseware assisted examinations compared with small-sized sections using traditional paper-and-pencil examinations, there appeared to be a severe disconnect between the final…

Application of pedagogy reflective in statistical methods course and practicum statistical methods

NASA Astrophysics Data System (ADS)

Julie, Hongki

2017-08-01

Subject Elementary Statistics, Statistical Methods and Statistical Methods Practicum aimed to equip students of Mathematics Education about descriptive statistics and inferential statistics. The students' understanding about descriptive and inferential statistics were important for students on Mathematics Education Department, especially for those who took the final task associated with quantitative research. In quantitative research, students were required to be able to present and describe the quantitative data in an appropriate manner, to make conclusions from their quantitative data, and to create relationships between independent and dependent variables were defined in their research. In fact, when students made their final project associated with quantitative research, it was not been rare still met the students making mistakes in the steps of making conclusions and error in choosing the hypothetical testing process. As a result, they got incorrect conclusions. This is a very fatal mistake for those who did the quantitative research. There were some things gained from the implementation of reflective pedagogy on teaching learning process in Statistical Methods and Statistical Methods Practicum courses, namely: 1. Twenty two students passed in this course and and one student did not pass in this course. 2. The value of the most accomplished student was A that was achieved by 18 students. 3. According all students, their critical stance could be developed by them, and they could build a caring for each other through a learning process in this course. 4. All students agreed that through a learning process that they undergo in the course, they can build a caring for each other.

A Comparison of Computer-Assisted Instruction and the Traditional Method of Teaching Basic Statistics

ERIC Educational Resources Information Center

Ragasa, Carmelita Y.

2008-01-01

The objective of the study is to determine if there is a significant difference in the effects of the treatment and control groups on achievement as well as on attitude as measured by the posttest. A class of 38 sophomore college students in the basic statistics taught with the use of computer-assisted instruction and another class of 15 students…

Effects of the Afterschool Program on Student Achievement of Students with Disabilities in a Rural Georgia Middle School

ERIC Educational Resources Information Center

Franklin, Constance

2017-01-01

The purpose of this quantitative nonexperimental causal comparative research study is to determine if there is a statistically significant difference in reading and math achievement as measured by the Georgia Criterion-Referenced Competency Test (CRCT) for sixth, seventh, and eighth grade students with disabilities (SWD) who attended the…

Teacher Self-Efficacy: A Link to Student Achievement in English Language and Mathematics in Belizean Primary Schools

ERIC Educational Resources Information Center

Alvarez-Nunez, Tanya Mae

2012-01-01

Scope and Method of Study: This quantitative, non-experimental study sought to determine if a statistically significant difference existed in student achievement on the PSE exam in Belizean primary schools for students who have teachers with varying levels of self-efficacy (high, medium and low). The Teacher Efficacy Scale (TES), which captures…

Perceived self-efficacy and student-teacher relationships among diverse Title I students' achievement in science

NASA Astrophysics Data System (ADS)

Larry, Triaka A.

The need for more diversity in STEM-related careers and college majors is urgent. Self-efficacy and student-teacher relationships are factors that have been linked to influencing students’ pursuit of subject-specific careers and academic achievement. The impact of self-efficacy and student perceptions of teacher interpersonal behaviors on student achievement have been extensively researched in the areas of Mathematics and English, however, most studies using science achievement, as a criterion variable, were conducted using non-diverse, White upper middle class to affluent participants. In order to determine the strength of relationships between perceived science self-efficacy, and student perceptions of teacher interpersonal behaviors as factors that influence science achievement (science GPA), the Science Self-Efficacy Questionnaire (SSEQ) and Questionnaire on Teacher Interactions (QTI) were administered to twelfth grade students enrolled at a highly diverse urban Title I high school, while controlling for demographics, defined as gender, ethnicity, and minority status. Using a hierarchical multiple linear regression analysis, results demonstrated that the predictor variables (i.e., gender, ethnicity, minority status, science self-efficacy, and teacher interpersonal behaviors) accounted for 20.8% of the variance in science GPAs. Science self-efficacy made the strongest unique contribution to explaining science GPA, while minority status and gender were found to be statistically significant contributors to the full model as well. Ethnicity and teacher interpersonal behaviors did not make a statistically significant contribution to the variance in science GPA, and accounted for ≤ 1% of the variance. Implications and recommendations for future research are subsequently given.

Statistical and molecular analyses of evolutionary significance of red-green color vision and color blindness in vertebrates.

PubMed

Yokoyama, Shozo; Takenaka, Naomi

2005-04-01

Red-green color vision is strongly suspected to enhance the survival of its possessors. Despite being red-green color blind, however, many species have successfully competed in nature, which brings into question the evolutionary advantage of achieving red-green color vision. Here, we propose a new method of identifying positive selection at individual amino acid sites with the premise that if positive Darwinian selection has driven the evolution of the protein under consideration, then it should be found mostly at the branches in the phylogenetic tree where its function had changed. The statistical and molecular methods have been applied to 29 visual pigments with the wavelengths of maximal absorption at approximately 510-540 nm (green- or middle wavelength-sensitive [MWS] pigments) and at approximately 560 nm (red- or long wavelength-sensitive [LWS] pigments), which are sampled from a diverse range of vertebrate species. The results show that the MWS pigments are positively selected through amino acid replacements S180A, Y277F, and T285A and that the LWS pigments have been subjected to strong evolutionary conservation. The fact that these positively selected M/LWS pigments are found not only in animals with red-green color vision but also in those with red-green color blindness strongly suggests that both red-green color vision and color blindness have undergone adaptive evolution independently in different species.

Growing minds: The effect of school gardening programs on the science achievement of elementary students

NASA Astrophysics Data System (ADS)

Klemmer, Cynthia Davis

Science literacy refers to a basic knowledge and understanding of science concepts and processes needed to consider issues and make choices on a daily basis in an increasingly technology-driven society. A critical precursor to producing science literate adults is actively involving children in science while they are young. National and state (TX) science standards advocate the use of constructivist methods including hands-on, experiential activities that foster the development of science process skills through real-world investigations. School gardens show promise as a tool for implementing these guidelines by providing living laboratories for active science. Gardens offer opportunities for a variety of hands-on investigations, enabling students to apply and practice science skills. School gardens are increasing in popularity; however, little research data exists attesting to their actual effectiveness in enhancing students' science achievement. The study used a quasi-experimental posttest-only research design to assess the effects of a school gardening program on the science achievement of 3rd, 4th, and 5th grade elementary students. The sample consisted of 647 students from seven elementary schools in Temple, Texas. The experimental group participated in school gardening activities as part of their science curriculum. The control group did not garden and were taught using traditional classroom-based methods. Results showed higher scores for students in the experimental group which were statistically significant. Post-hoc tests using Scheffe's method revealed that these differences were attributed to the 5th grade. No statistical significance was found between girls and boys in the experimental group, indicating that gardening was equally effective for both genders. Within each gender, statistical significance was found between males in the experimental and control groups at all three grade levels, and for females in the 5 th grade. This research indicated that

Testing the effect of a science-enhanced curriculum on the science achievement and agricultural competency of secondary agricultural education students

NASA Astrophysics Data System (ADS)

Haynes, James Christopher

Scope and Method of Study. The purpose of this study was to determine if a science-enhanced curriculum produced by the Center for Agricultural and Environmental Research and Training (CAERT) taught in a secondary level animal science or horticulture course would improve students' understanding of selected scientific principles significantly, when compared to students who were instructed using a traditional curriculum. A secondary purpose was to determine the effect that the science-enhanced CAERT curriculum would have on students' agricultural knowledge when compared to students who were instructed using a traditional curriculum. The design of the study was ex post facto, causal comparative because no random assignment of the treatment group occurred. Findings and Conclusions. No statistically significant difference was found between the treatment and comparison groups regarding science achievement. However, the mean score of the treatment group was slightly larger than the comparison group indicating a slightly higher achievement level; a "Small" effect size (d = .16) for this difference was calculated. It was determined that a statistically significant difference (p < .05) existed in agriculture competency scores in animal science (p = .001) and horticulture (p = .000) as a result of the treatment. Moreover, this was considered to be a "very large" effect (d = 1.18) in animal science and a "large" effect (d = .92) in horticulture. When considering student achievement in science, this study found that the use of the science-enhanced CAERT curriculum did not result in a statistically significant increase (p < .05) in student performance as determined by the TerraNova3 science proficiency examination. However, students who were instructed using the CAERT curriculum scored better overall than those who were instructed using a "traditional" curriculum.

Predictors of cultural capital on science academic achievement at the 8th grade level

NASA Astrophysics Data System (ADS)

Misner, Johnathan Scott

The purpose of the study was to determine if students' cultural capital is a significant predictor of 8th grade science achievement test scores in urban locales. Cultural capital refers to the knowledge used and gained by the dominant class, which allows social and economic mobility. Cultural capital variables include magazines at home and parental education level. Other variables analyzed include socioeconomic status (SES), gender, and English language learners (ELL). This non-experimental study analyzed the results of the 2011 Eighth Grade Science National Assessment of Educational Progress (NAEP). The researcher analyzed the data using a multivariate stepwise regression analysis. The researcher concluded that the addition of cultural capital factors significantly increased the predictive power of the model where magazines in home, gender, student classified as ELL, parental education level, and SES were the independent variables and science achievement was the dependent variable. For alpha=0.05, the overall test for the model produced a R2 value of 0.232; therefore the model predicted 23.2% of variance in science achievement results. Other major findings include: higher measures of home resources predicted higher 2011 NAEP eighth grade science achievement; males were predicted to have higher 2011 NAEP 8 th grade science achievement; classified ELL students were predicted to score lower on the NAEP eight grade science achievement; higher parent education predicted higher NAEP eighth grade science achievement; lower measures of SES predicted lower 2011 NAEP eighth grade science achievement. This study contributed to the research in this field by identifying cultural capital factors that have been found to have statistical significance on predicting eighth grade science achievement results, which can lead to strategies to help improve science academic achievement among underserved populations.

Barriers to Academic Achievement for Foster Youth: The Story behind the Statistics

ERIC Educational Resources Information Center

Morton, Brenda M.

2015-01-01

The purpose of this qualitative research study was to explore the perceptions of former and current foster youth about the barriers they encountered during their K-12 education, and to learn how they overcame these obstacles and achieved academic success. The study included in-depth interviews of 11 participants, all of whom were current or former…

African-American college student attitudes toward physics and their effect on achievement

NASA Astrophysics Data System (ADS)

Drake, Carl Timothy

The purpose of this study was to investigate factors affecting the attitudes that African-American college students have towards introductory college physics. The population targeted for this study consisted of African-American males and females enrolled in introductory college physics classes at an urban public historical black college or university (HBCU) located in the southeastern United States. Nine of the Fennema-Sherman Mathematics Attitude Scales, modified for physics, were used to analyze the attitudes of the 135 participants enrolled in an introductory college physics class. The nine scales used to measure the students' attitudes were Attitude Toward Success in Physics Scale (AS), The Physics as a Male Domain Scale (MD), The Mother Scale (M), The Father Scale (F), The Teacher Scale (T), The Confidence in Learning Physics Scale (C), The Physics Anxiety Scale (A), The Effectance Motivation Scale in Physics (E), and The Physics Usefulness Scale (U). Hypothesis I states that there is a significant difference in the domain scores of African-American college students in the Fennema-Sherman Math Attitudes Scales adapted for physics. It was found using a repeated measures ANOVA that there was a significant difference between the attitudes of African-Americans on the nine attitude scales of the Fennema-Sherman Math Attitude Scales, F(8,992) = 43.09, p < .001. Hypothesis II states that there is a statistically significant difference in domain scores between African-American males and African-American females in the Fennema-Sherman Attitude Scales. It was found using a MANOVA that there was not a significant difference between the domain scores of African-American males and African-American females, F(8, 116) = .38, p > .05. Hypothesis III states that there is a statistically significant relationship between attitude towards physics and achievement for African-American students. The students with good attitudes toward physics would have a higher level of achievement

Self-Esteem and Academic Achievement of High School Students

ERIC Educational Resources Information Center

Moradi Sheykhjan, Tohid; Jabari, Kamran; Rajeswari, K.

2014-01-01

The primary purpose of this study was to determine the influence of self-esteem on academic achievement among high school students in Miandoab City of Iran. The methodology of the research is descriptive and correlation that descriptive and inferential statistics were used to analyze the data. Statistical Society includes male and female high…

The Relationship between Student Voice and Perceptions of Motivation, Attachment, Achievement and School Climate in Davidson and Rutherford Counties

ERIC Educational Resources Information Center

Matthews, Sharon Elizabeth

2010-01-01

This study investigated the extent to which there were statistically significant relationships between school administrators' systemic implementation of student voice work and student perceptions (i.e. achievement, motivation, attachment and school climate) and PLAN performance. Student voice was defined as students being equal partners in school…

An empirical examination of the effects of family commitment in education on student achievement in seventh grade science

NASA Astrophysics Data System (ADS)

Wang, Jianjun; Wildman, Louis

A national data base from the Longitudinal Study of American Youth (LSAY) was employed to examine the effects of family commitment in education on student achievement in seventh grade science. The backward elimination procedure in the Statistical Analysis System (SAS) was adopted in this study to select significant variables of family commitment at = .05. The results show that around 22% of the variance in student science achievement can be explained by the selected significant LSAY variables. An analysis of the impact of family commitment seems to indicate that parental education and encouragement are important factors in the improvement of student achievement. However, educators, including school personnel and parents, should exercise caution regarding how they help students with their homework and how they reward students for good grades.Received: 14 June 1994; Revised: 31 October 1994;

Student-generated illustrations and written narratives of biological science concepts: The effect on community college life science students' achievement in and attitudes toward science

NASA Astrophysics Data System (ADS)

Harvey, Robert Christopher

The purpose of this study was to determine the effects of two conceptually based instructional strategies on science achievement and attitudes of community college biological science students. The sample consisted of 277 students enrolled in General Biology 1, Microbiology, and Human Anatomy and Physiology 1. Control students were comprised of intact classes from the 2005 Spring semester; treatment students from the 2005 Fall semester were randomly assigned to one of two groups within each course: written narrative (WN) and illustration (IL). WN students prepared in-class written narratives related to cell theory and metabolism, which were taught in all three courses. IL students prepared in-class illustrations of the same concepts. Control students received traditional lecture/lab during the entire class period and neither wrote in-class descriptions nor prepared in-class illustrations of the targeted concepts. All groups were equivalent on age, gender, ethnicity, GPA, and number of college credits earned and were blinded to the study. All interventions occurred in class and no group received more attention or time to complete assignments. A multivariate analysis of covariance (MANCOVA) via multiple regression was the primary statistical strategy used to test the study's hypotheses. The model was valid and statistically significant. Independent follow-up univariate analyses relative to each dependent measure found that no research factor had a significant effect on attitude, but that course-teacher, group membership, and student academic characteristics had a significant effect (p < .05) on achievement: (1) Biology students scored significantly lower in achievement than A&P students; (2) Microbiology students scored significantly higher in achievement than Biology students; (3) Written Narrative students scored significantly higher in achievement than Control students; and (4) GPA had a significant effect on achievement. In addition, given p < .08: (1

Inverse statistics in the foreign exchange market

NASA Astrophysics Data System (ADS)

Jensen, M. H.; Johansen, A.; Petroni, F.; Simonsen, I.

2004-09-01

We investigate intra-day foreign exchange (FX) time series using the inverse statistic analysis developed by Simonsen et al. (Eur. Phys. J. 27 (2002) 583) and Jensen et al. (Physica A 324 (2003) 338). Specifically, we study the time-averaged distributions of waiting times needed to obtain a certain increase (decrease) ρ in the price of an investment. The analysis is performed for the Deutsch Mark (DM) against the US for the full year of 1998, but similar results are obtained for the Japanese Yen against the US. With high statistical significance, the presence of “resonance peaks” in the waiting time distributions is established. Such peaks are a consequence of the trading habits of the market participants as they are not present in the corresponding tick (business) waiting time distributions. Furthermore, a new stylized fact, is observed for the (normalized) waiting time distribution in the form of a power law Pdf. This result is achieved by rescaling of the physical waiting time by the corresponding tick time thereby partially removing scale-dependent features of the market activity.

Social–Emotional Factors Affecting Achievement Outcomes Among Disadvantaged Students: Closing the Achievement Gap

PubMed Central

Becker, Bronwyn E.; Luthar, Suniya S.

2012-01-01

Despite concentrated efforts at improving inferior academic outcomes among disadvantaged students, a substantial achievement gap between the test scores of these students and others remains (Jencks & Phillips, 1998; National Center for Education Statistics, 2000a, 2000b; Valencia & Suzuki, 2000). Existing research used ecological models to document social–emotional factors at multiple levels of influence that undermine academic performance. This article integrates ideas from various perspectives in a comprehensive and interdisciplinary model that will inform policy makers, administrators, and schools about the social–emotional factors that act as both risk and protective factors for disadvantaged students’ learning and opportunities for academic success. Four critical social–emotional components that influence achievement performance (academic and school attachment, teacher support, peer values, and mental health) are reviewed. PMID:23255834

Social-Emotional Factors Affecting Achievement Outcomes Among Disadvantaged Students: Closing the Achievement Gap.

PubMed

Becker, Bronwyn E; Luthar, Suniya S

2002-01-01

Despite concentrated efforts at improving inferior academic outcomes among disadvantaged students, a substantial achievement gap between the test scores of these students and others remains (Jencks & Phillips, 1998; National Center for Education Statistics, 2000a, 2000b; Valencia & Suzuki, 2000). Existing research used ecological models to document social-emotional factors at multiple levels of influence that undermine academic performance. This article integrates ideas from various perspectives in a comprehensive and interdisciplinary model that will inform policy makers, administrators, and schools about the social-emotional factors that act as both risk and protective factors for disadvantaged students' learning and opportunities for academic success. Four critical social-emotional components that influence achievement performance (academic and school attachment, teacher support, peer values, and mental health) are reviewed.

Worry, Intolerance of Uncertainty, and Statistics Anxiety

ERIC Educational Resources Information Center

Williams, Amanda S.

2013-01-01

Statistics anxiety is a problem for most graduate students. This study investigates the relationship between intolerance of uncertainty, worry, and statistics anxiety. Intolerance of uncertainty was significantly related to worry, and worry was significantly related to three types of statistics anxiety. Six types of statistics anxiety were…

Determinants of Academic Achievement of Middle Schoolers in Turkey

ERIC Educational Resources Information Center

Börkan, Bengü; Bakis, Ozan

2016-01-01

The purpose of this study is to discuss student and school factors, including cross level interaction, that cause inequalities in seven and eighth grade students' achievement in Turkish context by using national achievement test scores with a multi-level statistical approach. Our results are in line with most other studies with similar purpose.…

Stationary statistical theory of two-surface multipactor regarding all impacts for efficient threshold analysis

NASA Astrophysics Data System (ADS)

Lin, Shu; Wang, Rui; Xia, Ning; Li, Yongdong; Liu, Chunliang

2018-01-01

Statistical multipactor theories are critical prediction approaches for multipactor breakdown determination. However, these approaches still require a negotiation between the calculation efficiency and accuracy. This paper presents an improved stationary statistical theory for efficient threshold analysis of two-surface multipactor. A general integral equation over the distribution function of the electron emission phase with both the single-sided and double-sided impacts considered is formulated. The modeling results indicate that the improved stationary statistical theory can not only obtain equally good accuracy of multipactor threshold calculation as the nonstationary statistical theory, but also achieve high calculation efficiency concurrently. By using this improved stationary statistical theory, the total time consumption in calculating full multipactor susceptibility zones of parallel plates can be decreased by as much as a factor of four relative to the nonstationary statistical theory. It also shows that the effect of single-sided impacts is indispensable for accurate multipactor prediction of coaxial lines and also more significant for the high order multipactor. Finally, the influence of secondary emission yield (SEY) properties on the multipactor threshold is further investigated. It is observed that the first cross energy and the energy range between the first cross and the SEY maximum both play a significant role in determining the multipactor threshold, which agrees with the numerical simulation results in the literature.

Profile of middle school students on scientific literacy achievements by using scientific literacy assessments (SLA)

NASA Astrophysics Data System (ADS)

Rachmatullah, Arif; Diana, Sariwulan; Rustaman, Nuryani Y.

2016-02-01

Along with the development of science and technology, the basic ability to read, write and count is not enough just to be able to survive in the modern era that surrounded by the products of science and technology. Scientific literacy is an ability that might be added as basic ability for human in the modern era. Recently, Fives et al. developed a new scientific literacy assessment for students, named as SLA (Scientific Literacy Assessment). A pilot study on the achievements of scientific literacy of middle school students in Sumedang using SLA was conducted to investigate the profile scientific literacy achievement of 223 middle school students in Sumedang, and compare the outcomes between genders (159 girls and 64 boys) and school accreditation (A and B) using a quantitative method with descriptive research-school survey. Based on the results, the average achievement of scientific literacy Sumedang middle school students is 45.21 and classified as the low category. The five components of scientific literacy, which is only one component in the medium category, namely science motivation and beliefs, and the four other components are in the low and very low category. Boys have higher scientific literacy, but the differences not statistically significant. Student's scientific literacy in an accredited school is higher than B, and the differences are statistically significant. Recommendation for further are: involve more research subjects, add more number of questions for each indicator, and conduct an independent research for each component.

Does Children’s Academic Achievement Improve when Single Mothers Marry?

PubMed Central

Wagmiller, Robert L.; Gershoff, Elizabeth; Veliz, Philip; Clements, Margaret

2011-01-01

Promoting marriage, especially among low-income single mothers with children, is increasingly viewed as a promising public policy strategy for improving developmental outcomes for disadvantaged children. Previous research suggests, however, that children’s academic achievement either does not improve or declines when single mothers marry. In this paper, we argue that previous research may understate the benefits of mothers’ marriages to children from single-parent families because (1) the short-term and long-term developmental consequences of marriage are not adequately distinguished and (2) child and family contexts in which marriage is likely to confer developmental advantages are not differentiated from those that do not. Using multiple waves of data from the ECLS-K, we find that single mothers’ marriages are associated with modest but statistically significant improvements in their children’s academic achievement trajectories. However, only children from more advantaged single-parent families benefit from their mothers’ marriage. PMID:21611134

Differentiated Instruction in Developmental Mathematics Classes and Achievement of Ethnic Minority Students

ERIC Educational Resources Information Center

Hood, Otis D., Jr.

2012-01-01

National educational assessment organizations present statistical information that an achievement gap exists between White students and students of color. This achievement gap closely relates to students representing lower SES conditions. This study examined the lack of achievement for ethnic minorities in the field of mathematics using an…

A novel complete-case analysis to determine statistical significance between treatments in an intention-to-treat population of randomized clinical trials involving missing data.

PubMed

Liu, Wei; Ding, Jinhui

2018-04-01

The application of the principle of the intention-to-treat (ITT) to the analysis of clinical trials is challenged in the presence of missing outcome data. The consequences of stopping an assigned treatment in a withdrawn subject are unknown. It is difficult to make a single assumption about missing mechanisms for all clinical trials because there are complicated reactions in the human body to drugs due to the presence of complex biological networks, leading to data missing randomly or non-randomly. Currently there is no statistical method that can tell whether a difference between two treatments in the ITT population of a randomized clinical trial with missing data is significant at a pre-specified level. Making no assumptions about the missing mechanisms, we propose a generalized complete-case (GCC) analysis based on the data of completers. An evaluation of the impact of missing data on the ITT analysis reveals that a statistically significant GCC result implies a significant treatment effect in the ITT population at a pre-specified significance level unless, relative to the comparator, the test drug is poisonous to the non-completers as documented in their medical records. Applications of the GCC analysis are illustrated using literature data, and its properties and limits are discussed.

Null-space and statistical significance of first-arrival traveltime inversion

NASA Astrophysics Data System (ADS)

Morozov, Igor B.

2004-03-01

The strong uncertainty inherent in the traveltime inversion of first arrivals from surface sources is usually removed by using a priori constraints or regularization. This leads to the null-space (data-independent model variability) being inadequately sampled, and consequently, model uncertainties may be underestimated in traditional (such as checkerboard) resolution tests. To measure the full null-space model uncertainties, we use unconstrained Monte Carlo inversion and examine the statistics of the resulting model ensembles. In an application to 1-D first-arrival traveltime inversion, the τ-p method is used to build a set of models that are equivalent to the IASP91 model within small, ~0.02 per cent, time deviations. The resulting velocity variances are much larger, ~2-3 per cent within the regions above the mantle discontinuities, and are interpreted as being due to the null-space. Depth-variant depth averaging is required for constraining the velocities within meaningful bounds, and the averaging scalelength could also be used as a measure of depth resolution. Velocity variances show structure-dependent, negative correlation with the depth-averaging scalelength. Neither the smoothest (Herglotz-Wiechert) nor the mean velocity-depth functions reproduce the discontinuities in the IASP91 model; however, the discontinuities can be identified by the increased null-space velocity (co-)variances. Although derived for a 1-D case, the above conclusions also relate to higher dimensions.

Miami-Dade County Public Schools Statistical Abstract 2006-2007

ERIC Educational Resources Information Center

Research Services, Miami-Dade County Public Schools, 2007

2007-01-01

The purpose of this document is to present, in summary fashion, statistical information on the status of public education in Miami-Dade County. Information is provided in the areas of organization, educational programs and services, achievement, and other outcomes of schooling. Also included are multi-year statistics on student population,…

Miami-Dade County Public Schools Statistical Abstract 2005-2006

ERIC Educational Resources Information Center

Research Services, Miami-Dade County Public Schools, 2006

2006-01-01

The purpose of this document is to present, in summary fashion, statistical information on the status of public education in Miami-Dade County. Information is provided in the areas of organization, educational programs and services, achievement, and other outcomes of schooling. Also included are multi-year statistics on student population,…

Miami-Dade County Public Schools Statistical Abstract 2004-2005

ERIC Educational Resources Information Center

Research Services, Miami-Dade County Public Schools, 2005

2005-01-01

The purpose of this document is to present, in summary fashion, statistical information on the status of public education in Miami-Dade County. Information is provided in the areas of organization, educational programs and services, achievement, and other outcomes of schooling. Also included are multi-year statistics on student population,…

Miami-Dade County Public Schools Statistical Abstract 2007-2008

ERIC Educational Resources Information Center

Research Services, Miami-Dade County Public Schools, 2008

2008-01-01

The purpose of this document is to present, in summary fashion, statistical information on the status of public education in Miami-Dade County. Information is provided in the areas of organization, educational programs and services, achievement, and other outcomes of schooling. Also included are multi-year statistics on student population,…

Factors related to student performance in statistics courses in Lebanon

NASA Astrophysics Data System (ADS)

Naccache, Hiba Salim

The purpose of the present study was to identify factors that may contribute to business students in Lebanese universities having difficulty in introductory and advanced statistics courses. Two statistics courses are required for business majors at Lebanese universities. Students are not obliged to be enrolled in any math courses prior to taking statistics courses. Drawing on recent educational research, this dissertation attempted to identify the relationship between (1) students’ scores on Lebanese university math admissions tests; (2) students’ scores on a test of very basic mathematical concepts; (3) students’ scores on the survey of attitude toward statistics (SATS); (4) course performance as measured by students’ final scores in the course; and (5) their scores on the final exam. Data were collected from 561 students enrolled in multiple sections of two courses: 307 students in the introductory statistics course and 260 in the advanced statistics course in seven campuses across Lebanon over one semester. The multiple regressions results revealed four significant relationships at the introductory level: between students’ scores on the math quiz with their (1) final exam scores; (2) their final averages; (3) the Cognitive subscale of the SATS with their final exam scores; and (4) their final averages. These four significant relationships were also found at the advanced level. In addition, two more significant relationships were found between students’ final average and the two subscales of Effort (5) and Affect (6). No relationship was found between students’ scores on the admission math tests and both their final exam scores and their final averages in both the introductory and advanced level courses. On the other hand, there was no relationship between students’ scores on Lebanese admissions tests and their final achievement. Although these results were consistent across course formats and instructors, they may encourage Lebanese universities

Music and Achievement.

ERIC Educational Resources Information Center

Smith, Ben A.; Davidson, Charles W.

1991-01-01

Discusses a study of the effects of music listening upon student achievement. Reports that seventh grade students listened to music while independently studying the earth-sun relationship. Concludes that there were no significant achievement differences among students who learned while listening to rock, classical, easy listening, or no music. (SG)

Assessing attitudes towards statistics among medical students: psychometric properties of the Serbian version of the Survey of Attitudes Towards Statistics (SATS).

PubMed

Stanisavljevic, Dejana; Trajkovic, Goran; Marinkovic, Jelena; Bukumiric, Zoran; Cirkovic, Andja; Milic, Natasa

2014-01-01

Medical statistics has become important and relevant for future doctors, enabling them to practice evidence based medicine. Recent studies report that students' attitudes towards statistics play an important role in their statistics achievements. The aim of the study was to test the psychometric properties of the Serbian version of the Survey of Attitudes Towards Statistics (SATS) in order to acquire a valid instrument to measure attitudes inside the Serbian educational context. The validation study was performed on a cohort of 417 medical students who were enrolled in an obligatory introductory statistics course. The SATS adaptation was based on an internationally accepted methodology for translation and cultural adaptation. Psychometric properties of the Serbian version of the SATS were analyzed through the examination of factorial structure and internal consistency. Most medical students held positive attitudes towards statistics. The average total SATS score was above neutral (4.3±0.8), and varied from 1.9 to 6.2. Confirmatory factor analysis validated the six-factor structure of the questionnaire (Affect, Cognitive Competence, Value, Difficulty, Interest and Effort). Values for fit indices TLI (0.940) and CFI (0.961) were above the cut-off of ≥0.90. The RMSEA value of 0.064 (0.051-0.078) was below the suggested value of ≤0.08. Cronbach's alpha of the entire scale was 0.90, indicating scale reliability. In a multivariate regression model, self-rating of ability in mathematics and current grade point average were significantly associated with the total SATS score after adjusting for age and gender. Present study provided the evidence for the appropriate metric properties of the Serbian version of SATS. Confirmatory factor analysis validated the six-factor structure of the scale. The SATS might be reliable and a valid instrument for identifying medical students' attitudes towards statistics in the Serbian educational context.

Weighted statistical parameters for irregularly sampled time series

NASA Astrophysics Data System (ADS)

Rimoldini, Lorenzo

2014-01-01

Unevenly spaced time series are common in astronomy because of the day-night cycle, weather conditions, dependence on the source position in the sky, allocated telescope time and corrupt measurements, for example, or inherent to the scanning law of satellites like Hipparcos and the forthcoming Gaia. Irregular sampling often causes clumps of measurements and gaps with no data which can severely disrupt the values of estimators. This paper aims at improving the accuracy of common statistical parameters when linear interpolation (in time or phase) can be considered an acceptable approximation of a deterministic signal. A pragmatic solution is formulated in terms of a simple weighting scheme, adapting to the sampling density and noise level, applicable to large data volumes at minimal computational cost. Tests on time series from the Hipparcos periodic catalogue led to significant improvements in the overall accuracy and precision of the estimators with respect to the unweighted counterparts and those weighted by inverse-squared uncertainties. Automated classification procedures employing statistical parameters weighted by the suggested scheme confirmed the benefits of the improved input attributes. The classification of eclipsing binaries, Mira, RR Lyrae, Delta Cephei and Alpha2 Canum Venaticorum stars employing exclusively weighted descriptive statistics achieved an overall accuracy of 92 per cent, about 6 per cent higher than with unweighted estimators.

Significance of specificity of Tinetti B-POMA test and fall risk factor in third age of life.

PubMed

Avdić, Dijana; Pecar, Dzemal

2006-02-01

As for the third age, psychophysical abilities of humans gradually decrease, while the ability of adaptation to endogenous and exogenous burdens is going down. In 1987, "Harada" et al. (1) have found out that 9.5 million persons in USA have difficulties running daily activities, while 59% of them (which is 5.6 million) are older than 65 years in age. The study has encompassed 77 questioned persons of both sexes with their average age 71.73 +/- 5.63 (scope of 65-90 years in age), chosen by random sampling. Each patient has been questioned in his/her own home and familiar to great extent with the methodology and aims of the questionnaire. Percentage of questioned women was 64.94% (50 patients) while the percentage for men was 35.06% (27 patients). As for the value of risk factor score achieved conducting the questionnaire and B-POMA test, there are statistically significant differences between men and women, as well as between patients who fell and those who never did. As for the way of life (alone or in the community), there are no significant statistical differences. Average results gained through B-POMA test in this study are statistically significantly higher in men and patients who did not provide data about falling, while there was no statistically significant difference in the way of life. In relation to the percentage of maximum number of positive answers to particular questions, regarding gender, way of life and the data about falling, there were no statistically significant differences between the value of B-POMA test and the risk factor score (the questionnaire).

Relationship between the Wide Range Achievement Test 3 and the Wechsler Individual Achievement Test.

PubMed

Smith, T D; Smith, B L

1998-12-01

The present study examined the relationship between the Wide Range Achievement Test 3 and the Wechsler Individual Achievement Test for a sample of children with learning disabilities in two rural school districts. Data were collected for 87 school children who had been classified as learning disabled and placed in special education resource services. Pearson product-moment correlations between scores on the two measures were significant and moderate to high; however, mean scores were not significantly different on Reading, Spelling, and Arithmetic subtests of the Wide Range Achievement Test 3 compared to those for the basic Reading, Spelling, and Mathematics Reasoning subtests of the Wechsler Individual Achievement Test. Although there were significant mean differences between scores on Reading and Reading Comprehension and on Arithmetic and Numerical Operations, magnitudes were small. It appears that the two tests provide similar results when screening for reading, spelling, and arithmetic.

School Vouchers and Student Achievement: Recent Evidence and Remaining Questions

ERIC Educational Resources Information Center

Rouse, Cecilia Elena; Barrow, Lisa

2009-01-01

In this article, we review the empirical evidence on the impact of education vouchers on student achievement and briefly discuss the evidence from other forms of school choice. The best research to date finds relatively small achievement gains for students offered education vouchers, most of which are not statistically different from zero.…

Effects of metacognitive instruction on the academic achievement of students in the secondary sciences

NASA Astrophysics Data System (ADS)

Bianchi, Gregory A.

The purpose of this study was to investigate the effects of reflective assessment in the form of situated metacognitive prompts on student achievement in the secondary sciences. A second goal was to determine whether specific gender differences existed in terms of student responsiveness to the metacognitive interventions. Participants in the study consisted of a convenience sample from a population of ninth-grade honors biology students in a large suburban school district located near Seattle, Washington. Beyond answering the specific research questions raised in this study, an additional aim was to broaden the growing body of research pertaining to the effect of metacognition on student achievement. A quasi-experimental, non-equivalent control group design was employed in this study. Descriptive and inferential statistics were computed to address the specific research questions raised. Specifically, a three-way repeated-measures ANOVA was performed. For this purpose, a single within-subjects factor, termed Testing, was defined. Three levels were allocated to this factor, and quantitative data from the Pretest, Posttest, and Retention Test were assigned to the levels, respectively. Group and Gender were defined as between-subjects factors, and both were allocated two levels; the two Group levels were Reflective and Non-Reflective. The effects of Group and Gender on each of the three quantitative measures were examined singly and in interaction with each other. Tests of statistical significance were analyzed at the .05 level. There was a statistically significant effect for Group (Reflective, Non-Reflective) by Testing (Pretest, Posttest, Retention Test). A three-way repeated-measures ANOVA procedure revealed that students in the Reflective group outperformed students in the Non-Reflective group (F = 10.258, p = .002, Partial eta 2 = .088). According to the effect size estimate, almost 9% of variance in the Testing variable was attributable to the Group variable

Pethidine efficacy in achieving the ultrasound-guided oblique subcostal transversus abdominis plane block in laparoscopic cholecystectomy: A prospective study.

PubMed

Breazu, Caius Mihai; Ciobanu, Lidia; Bartos, Adrian; Bodea, Raluca; Mircea, Petru Adrian; Ionescu, Daniela

2017-02-21

Pethidine is a synthetic opioid with local anesthetic properties. Our goal was to evaluate the analgesic efficacy of pethidine for achieving the ultrasound-guided oblique subcostal transversus abdominis plane (OSTAP) block in laparoscopic cholecystectomy. This prospective, double-blind study included 79 patients of physical status I and II according to American Society of Anesthesiologists, scheduled for elective laparoscopic cholecystectomy. The patients were randomly allocated into three groups, depending on the drug used to achieve preoperative bilateral OSTAP block: 1) OSTAP-Placebo (treated with normal saline); 2) OSTAP-Bupivacaine (treated with 0.25% bupivacaine); and 3) OSTAP-Pethidine (treated with 1% pethidine). The efficacy of pethidine in achieving the OSTAP block was analyzed using visual analog scale (VAS), intraoperative opioid dose, opioid consumption in post anesthesia care unit, and opioid consumption in the first 24 postoperative hours. The pain scores assessed by VAS at 0, 2, 4, 6, 12, and 24 hours were significantly lower in OSTAP-Pethidine than in OSTAP-Placebo group (p < 0.001). The mean intraoperative opioid consumption was significantly lower in OSTAP-Pethidine compared to OSTAP-Placebo group (150 versus 400 mg, p < 0.001), as well as the mean opioid consumption in the first 24 hours (20.4 versus 78 mg, p < 0.001). Comparing VAS assessment between OSTAP-Bupivacaine and OSTAP-Pethidine groups, statistically significant differences were observed only for the immediate postoperative pain assessment (0 hours), where lower values were observed in OSTAP-Pethidine group (p = 0.004). There were no statistically significant differences in the incidence of postoperative nausea and vomiting (p = 0.131) between the groups. The use of 1% pethidine can be an alternative to 0.25% bupivacaine in achieving OSTAP block for laparoscopic cholecystectomy.

Analysis of variance to assess statistical significance of Laplacian estimation accuracy improvement due to novel variable inter-ring distances concentric ring electrodes.

PubMed

Makeyev, Oleksandr; Joe, Cody; Lee, Colin; Besio, Walter G

2017-07-01

Concentric ring electrodes have shown promise in non-invasive electrophysiological measurement demonstrating their superiority to conventional disc electrodes, in particular, in accuracy of Laplacian estimation. Recently, we have proposed novel variable inter-ring distances concentric ring electrodes. Analytic and finite element method modeling results for linearly increasing distances electrode configurations suggested they may decrease the truncation error resulting in more accurate Laplacian estimates compared to currently used constant inter-ring distances configurations. This study assesses statistical significance of Laplacian estimation accuracy improvement due to novel variable inter-ring distances concentric ring electrodes. Full factorial design of analysis of variance was used with one categorical and two numerical factors: the inter-ring distances, the electrode diameter, and the number of concentric rings in the electrode. The response variables were the Relative Error and the Maximum Error of Laplacian estimation computed using a finite element method model for each of the combinations of levels of three factors. Effects of the main factors and their interactions on Relative Error and Maximum Error were assessed and the obtained results suggest that all three factors have statistically significant effects in the model confirming the potential of using inter-ring distances as a means of improving accuracy of Laplacian estimation.

Defining the ecological hydrology of Taiwan Rivers using multivariate statistical methods

NASA Astrophysics Data System (ADS)

Chang, Fi-John; Wu, Tzu-Ching; Tsai, Wen-Ping; Herricks, Edwin E.

2009-09-01

SummaryThe identification and verification of ecohydrologic flow indicators has found new support as the importance of ecological flow regimes is recognized in modern water resources management, particularly in river restoration and reservoir management. An ecohydrologic indicator system reflecting the unique characteristics of Taiwan's water resources and hydrology has been developed, the Taiwan ecohydrological indicator system (TEIS). A major challenge for the water resources community is using the TEIS to provide environmental flow rules that improve existing water resources management. This paper examines data from the extensive network of flow monitoring stations in Taiwan using TEIS statistics to define and refine environmental flow options in Taiwan. Multivariate statistical methods were used to examine TEIS statistics for 102 stations representing the geographic and land use diversity of Taiwan. The Pearson correlation coefficient showed high multicollinearity between the TEIS statistics. Watersheds were separated into upper and lower-watershed locations. An analysis of variance indicated significant differences between upstream, more natural, and downstream, more developed, locations in the same basin with hydrologic indicator redundancy in flow change and magnitude statistics. Issues of multicollinearity were examined using a Principal Component Analysis (PCA) with the first three components related to general flow and high/low flow statistics, frequency and time statistics, and quantity statistics. These principle components would explain about 85% of the total variation. A major conclusion is that managers must be aware of differences among basins, as well as differences within basins that will require careful selection of management procedures to achieve needed flow regimes.

Evaluating statistical and clinical significance of intervention effects in single-case experimental designs: an SPSS method to analyze univariate data.

PubMed

Maric, Marija; de Haan, Else; Hogendoorn, Sanne M; Wolters, Lidewij H; Huizenga, Hilde M

2015-03-01

Single-case experimental designs are useful methods in clinical research practice to investigate individual client progress. Their proliferation might have been hampered by methodological challenges such as the difficulty applying existing statistical procedures. In this article, we describe a data-analytic method to analyze univariate (i.e., one symptom) single-case data using the common package SPSS. This method can help the clinical researcher to investigate whether an intervention works as compared with a baseline period or another intervention type, and to determine whether symptom improvement is clinically significant. First, we describe the statistical method in a conceptual way and show how it can be implemented in SPSS. Simulation studies were performed to determine the number of observation points required per intervention phase. Second, to illustrate this method and its implications, we present a case study of an adolescent with anxiety disorders treated with cognitive-behavioral therapy techniques in an outpatient psychotherapy clinic, whose symptoms were regularly assessed before each session. We provide a description of the data analyses and results of this case study. Finally, we discuss the advantages and shortcomings of the proposed method. Copyright © 2014. Published by Elsevier Ltd.

Performance studies of GooFit on GPUs vs RooFit on CPUs while estimating the statistical significance of a new physical signal

NASA Astrophysics Data System (ADS)

Di Florio, Adriano

2017-10-01

In order to test the computing capabilities of GPUs with respect to traditional CPU cores a high-statistics toy Monte Carlo technique has been implemented both in ROOT/RooFit and GooFit frameworks with the purpose to estimate the statistical significance of the structure observed by CMS close to the kinematical boundary of the J/ψϕ invariant mass in the three-body decay B + → J/ψϕK +. GooFit is a data analysis open tool under development that interfaces ROOT/RooFit to CUDA platform on nVidia GPU. The optimized GooFit application running on GPUs hosted by servers in the Bari Tier2 provides striking speed-up performances with respect to the RooFit application parallelised on multiple CPUs by means of PROOF-Lite tool. The considerable resulting speed-up, evident when comparing concurrent GooFit processes allowed by CUDA Multi Process Service and a RooFit/PROOF-Lite process with multiple CPU workers, is presented and discussed in detail. By means of GooFit it has also been possible to explore the behaviour of a likelihood ratio test statistic in different situations in which the Wilks Theorem may or may not apply because its regularity conditions are not satisfied.

How the Mastery Rubric for Statistical Literacy Can Generate Actionable Evidence about Statistical and Quantitative Learning Outcomes

ERIC Educational Resources Information Center

Tractenberg, Rochelle E.

2017-01-01

Statistical literacy is essential to an informed citizenry; and two emerging trends highlight a growing need for training that achieves this literacy. The first trend is towards "big" data: while automated analyses can exploit massive amounts of data, the interpretation--and possibly more importantly, the replication--of results are…

Intended and Achieved Torque of Implant Abutment's Screw using Manual Wrenches in Simulated Clinical Setting.

PubMed

Al-Otaibi, Hanan N

2016-11-01

To measure the difference between the intended torque and the achieved torque by the operator using the spring-style mechanical torque-limiting device (MTLD). Inexperienced and experienced clinicians used one spring-type MTLD to torque two abutment screws of each anterior and posterior implants, which were attached to two digital torque meters through a jaw model. The jaw model was part of a preclinical bench manikin attached to a dental chair. The intended torque value was 35 N cm (recommended by manufacturer) and the technique of torquing was observed for all the participants (instantaneous and repeated). The mean torque value was calculated for each subject for the anterior and posterior implants independently; t-test was used to compare between the intended and achieved torque values and to compare between the experienced and inexperienced clinicians (p ≤ 0.05). Thirty-seven clinicians participated, with an overall mean torque value of 34.30 N cm. The mean torque value of the achieved torque (34.30 ± 4.13 N cm) was statistically significantly less than the intended torque (p = 0.041). The male clinicians produced more statistically significantly accurate torque value (34.54 ± 3.78 N cm) than the female clinicians (p = 0.034), and the experienced clinicians produced more accurate torque values (34.9 ± 5.13 N cm) than the inexperienced clinicians (p = 0.048). Within the limitation of this study, the use of MTLDs did not always produce consistent torque values and the technique by which the operators use the MTLD might affect the torque value.

Determination of quality parameters from statistical analysis of routine TLD dosimetry data.

PubMed

German, U; Weinstein, M; Pelled, O

2006-01-01

Following the as low as reasonably achievable (ALARA) practice, there is a need to measure very low doses, of the same order of magnitude as the natural background, and the limits of detection of the dosimetry systems. The different contributions of the background signals to the total zero dose reading of thermoluminescence dosemeter (TLD) cards were analysed by using the common basic definitions of statistical indicators: the critical level (L(C)), the detection limit (L(D)) and the determination limit (L(Q)). These key statistical parameters for the system operated at NRC-Negev were quantified, based on the history of readings of the calibration cards in use. The electronic noise seems to play a minor role, but the reading of the Teflon coating (without the presence of a TLD crystal) gave a significant contribution.

A quasi-experimental study of maternal smoking during pregnancy and offspring academic achievement

PubMed Central

D'Onofrio, Brian M.; Singh, Amber L.; Iliadou, Anastasia; Lambe, Mats; Hultman, Christina M.; Neiderhiser, Jenae M.; Långström, Niklas; Lichtenstein, Paul

2013-01-01

Maternal smoking during pregnancy (SDP) is associated with lower academic achievement in offspring. The current study, which was based on all births in Sweden from 1983 through 1991, explored the possible causal processes underlying the association between SDP and offspring school grades and a standardized assessment of mathematic proficiency at age 15. The analyses compared relatives who varied in their exposure to SDP and who varied in their genetic relatedness. Although SDP was statistically associated with academic achievement when comparing unrelated individuals, the results suggest that SDP does not cause poorer academic performance, as full siblings differentially exposed to SDP did not differ in their academic scores. The pattern of results suggests that genetic factors shared by parents and their offspring explain significant variance in why offspring opposed to SDP have lower levels of academic achievement. Nevertheless, SDP impacts pregnancy-related outcomes. Reducing SDP, therefore, remains a major public health issue. PMID:20331655

Parents' Attitudes Towards Science and their Children's Science Achievement

NASA Astrophysics Data System (ADS)

Perera, Liyanage Devangi H.

2014-12-01

Although countries worldwide are emphasizing the importance of science education for technological development and global economic competition, comparative findings from standardized international student assessments reveal a huge gap in science scores between developed and developing countries. Certain developed economies too have made little progress in raising science achievement over the past decade. Despite school improvement being placed high on the policy agenda, the results of such actions have been poor. Therefore, there is a need to explore additional ways in which science achievement can be enhanced. This study focuses on the family and examines whether parents' attitudes towards science (how much they value science and the importance they place on it) can influence their children's science achievement. Individual- and school-level data are obtained from the Program for International Student Assessment 2006 survey for 15 Organisation for Economic Co-operation and Development (OECD) and non-OECD countries. Hierarchical linear modelling is employed to estimate the equations. The findings indicate that parents' attitudes towards science have a positive and statistically significant effect on science achievement, after controlling for other important student- and school-level variables. Moreover, students from poor backgrounds appear to benefit from more positive parental science attitudes as much as students from high socioeconomic status, such that equality of student achievement is not affected. This study recommends that schools and teachers encourage parents to play a more pro-active role in their children's science education, as well as educate parents about the importance of science and strategies that can be adopted to support their children's science learning.

The Ontology of Biological and Clinical Statistics (OBCS) for standardized and reproducible statistical analysis.

PubMed

Zheng, Jie; Harris, Marcelline R; Masci, Anna Maria; Lin, Yu; Hero, Alfred; Smith, Barry; He, Yongqun

2016-09-14

Statistics play a critical role in biological and clinical research. However, most reports of scientific results in the published literature make it difficult for the reader to reproduce the statistical analyses performed in achieving those results because they provide inadequate documentation of the statistical tests and algorithms applied. The Ontology of Biological and Clinical Statistics (OBCS) is put forward here as a step towards solving this problem. The terms in OBCS including 'data collection', 'data transformation in statistics', 'data visualization', 'statistical data analysis', and 'drawing a conclusion based on data', cover the major types of statistical processes used in basic biological research and clinical outcome studies. OBCS is aligned with the Basic Formal Ontology (BFO) and extends the Ontology of Biomedical Investigations (OBI), an OBO (Open Biological and Biomedical Ontologies) Foundry ontology supported by over 20 research communities. Currently, OBCS comprehends 878 terms, representing 20 BFO classes, 403 OBI classes, 229 OBCS specific classes, and 122 classes imported from ten other OBO ontologies. We discuss two examples illustrating how the ontology is being applied. In the first (biological) use case, we describe how OBCS was applied to represent the high throughput microarray data analysis of immunological transcriptional profiles in human subjects vaccinated with an influenza vaccine. In the second (clinical outcomes) use case, we applied OBCS to represent the processing of electronic health care data to determine the associations between hospital staffing levels and patient mortality. Our case studies were designed to show how OBCS can be used for the consistent representation of statistical analysis pipelines under two different research paradigms. Other ongoing projects using OBCS for statistical data processing are also discussed. The OBCS source code and documentation are available at: https://github.com/obcs/obcs . The Ontology

Nursing students' attitudes toward statistics: Effect of a biostatistics course and association with examination performance.

PubMed

Kiekkas, Panagiotis; Panagiotarou, Aliki; Malja, Alvaro; Tahirai, Daniela; Zykai, Rountina; Bakalis, Nick; Stefanopoulos, Nikolaos

2015-12-01

Although statistical knowledge and skills are necessary for promoting evidence-based practice, health sciences students have expressed anxiety about statistics courses, which may hinder their learning of statistical concepts. To evaluate the effects of a biostatistics course on nursing students' attitudes toward statistics and to explore the association between these attitudes and their performance in the course examination. One-group quasi-experimental pre-test/post-test design. Undergraduate nursing students of the fifth or higher semester of studies, who attended a biostatistics course. Participants were asked to complete the pre-test and post-test forms of The Survey of Attitudes Toward Statistics (SATS)-36 scale at the beginning and end of the course respectively. Pre-test and post-test scale scores were compared, while correlations between post-test scores and participants' examination performance were estimated. Among 156 participants, post-test scores of the overall SATS-36 scale and of the Affect, Cognitive Competence, Interest and Effort components were significantly higher than pre-test ones, indicating that the course was followed by more positive attitudes toward statistics. Among 104 students who participated in the examination, higher post-test scores of the overall SATS-36 scale and of the Affect, Difficulty, Interest and Effort components were significantly but weakly correlated with higher examination performance. Students' attitudes toward statistics can be improved through appropriate biostatistics courses, while positive attitudes contribute to higher course achievements and possibly to improved statistical skills in later professional life. Copyright © 2015 Elsevier Ltd. All rights reserved.

School Libraries and Science Achievement: A View from Michigan's Middle Schools

ERIC Educational Resources Information Center

Mardis, Marcia

2007-01-01

If strong school library media centers (SLMCs) positively impact middle school student reading achievement, as measured on standardized tests, are they also beneficial for middle school science achievement? To answer this question, the researcher built upon the statistical analyses used in previous school library impact studies with qualitative…

The effects of guided inquiry instruction on student achievement in high school biology

NASA Astrophysics Data System (ADS)

Vass, Laszlo

The purpose of this quantitative, quasi-experimental study was to measure the effect of a student-centered instructional method called guided inquiry on the achievement of students in a unit of study in high school biology. The study used a non-random sample of 109 students, the control group of 55 students enrolled in high school one, received teacher centered instruction while the experimental group of 54 students enrolled at high school two received student-centered, guided inquiry instruction. The pretest-posttest design of the study analyzed scores using an independent t-test, a dependent t-test (p = <.001), an ANCOVA (p = .007), mixed method ANOVA (p = .024) and hierarchical linear regression (p = <.001). The experimental group that received guided inquiry instruction had statistically significantly higher achievement than the control group.

Statistical Significance and Baseline Monitoring.

DTIC Science & Technology

1984-07-01

impacted at once........................... 24 6 Observed versus nominal a levels for multivariate tests of data sets (50 runs of 4 groups each...cumulative proportion of the observations found for each nominal level. The results of the comparisons of the observed versus nominal a levels for the...a values are always higher than nominal levels. Virtual- . .,ly all nominal a levels are below 0.20. In other words, the discriminant analysis models

Teaching Statistics in Biology: Using Inquiry-based Learning to Strengthen Understanding of Statistical Analysis in Biology Laboratory Courses

PubMed Central

2008-01-01

There is an increasing need for students in the biological sciences to build a strong foundation in quantitative approaches to data analyses. Although most science, engineering, and math field majors are required to take at least one statistics course, statistical analysis is poorly integrated into undergraduate biology course work, particularly at the lower-division level. Elements of statistics were incorporated into an introductory biology course, including a review of statistics concepts and opportunity for students to perform statistical analysis in a biological context. Learning gains were measured with an 11-item statistics learning survey instrument developed for the course. Students showed a statistically significant 25% (p < 0.005) increase in statistics knowledge after completing introductory biology. Students improved their scores on the survey after completing introductory biology, even if they had previously completed an introductory statistics course (9%, improvement p < 0.005). Students retested 1 yr after completing introductory biology showed no loss of their statistics knowledge as measured by this instrument, suggesting that the use of statistics in biology course work may aid long-term retention of statistics knowledge. No statistically significant differences in learning were detected between male and female students in the study. PMID:18765754

Teaching statistics in biology: using inquiry-based learning to strengthen understanding of statistical analysis in biology laboratory courses.

PubMed

Metz, Anneke M

2008-01-01

There is an increasing need for students in the biological sciences to build a strong foundation in quantitative approaches to data analyses. Although most science, engineering, and math field majors are required to take at least one statistics course, statistical analysis is poorly integrated into undergraduate biology course work, particularly at the lower-division level. Elements of statistics were incorporated into an introductory biology course, including a review of statistics concepts and opportunity for students to perform statistical analysis in a biological context. Learning gains were measured with an 11-item statistics learning survey instrument developed for the course. Students showed a statistically significant 25% (p < 0.005) increase in statistics knowledge after completing introductory biology. Students improved their scores on the survey after completing introductory biology, even if they had previously completed an introductory statistics course (9%, improvement p < 0.005). Students retested 1 yr after completing introductory biology showed no loss of their statistics knowledge as measured by this instrument, suggesting that the use of statistics in biology course work may aid long-term retention of statistics knowledge. No statistically significant differences in learning were detected between male and female students in the study.

Race, Socioeconomic Status, and Implicit Bias: Implications for Closing the Achievement Gap

NASA Astrophysics Data System (ADS)

Schlosser, Elizabeth Auretta Cox

This study accessed the relationship between race, socioeconomic status, age and the race implicit bias held by middle and high school science teachers in Mobile and Baldwin County Public School Systems. Seventy-nine participants were administered the race Implicit Association Test (race IAT), created by Greenwald, A. G., Nosek, B. A., & Banaji, M. R., (2003) and a demographic survey. Quantitative analysis using analysis of variances, ANOVA and t-tests were used in this study. An ANOVA was performed comparing the race IAT scores of African American science teachers and their Caucasian counterparts. A statically significant difference was found (F = .4.56, p = .01). An ANOVA was also performed using the race IAT scores comparing the age of the participants; the analysis yielded no statistical difference based on age. A t-test was performed comparing the race IAT scores of African American teachers who taught at either Title I or non-Title I schools; no statistical difference was found between groups (t = -17.985, p < .001). A t-test was also performed comparing the race IAT scores of Caucasian teachers who taught at either Title I or non-Title I schools; a statistically significant difference was found between groups ( t = 2.44, p > .001). This research examines the implications of the achievement gap among African American and Caucasian students in science.

Statistical Method to Overcome Overfitting Issue in Rational Function Models

NASA Astrophysics Data System (ADS)

Alizadeh Moghaddam, S. H.; Mokhtarzade, M.; Alizadeh Naeini, A.; Alizadeh Moghaddam, S. A.

2017-09-01

Rational function models (RFMs) are known as one of the most appealing models which are extensively applied in geometric correction of satellite images and map production. Overfitting is a common issue, in the case of terrain dependent RFMs, that degrades the accuracy of RFMs-derived geospatial products. This issue, resulting from the high number of RFMs' parameters, leads to ill-posedness of the RFMs. To tackle this problem, in this study, a fast and robust statistical approach is proposed and compared to Tikhonov regularization (TR) method, as a frequently-used solution to RFMs' overfitting. In the proposed method, a statistical test, namely, significance test is applied to search for the RFMs' parameters that are resistant against overfitting issue. The performance of the proposed method was evaluated for two real data sets of Cartosat-1 satellite images. The obtained results demonstrate the efficiency of the proposed method in term of the achievable level of accuracy. This technique, indeed, shows an improvement of 50-80% over the TR.

Comparison of student achievement among two science laboratory types: traditional and virtual

NASA Astrophysics Data System (ADS)

Reese, Mary Celeste

Technology has changed almost every aspect of our daily lives. It is not surprising then that technology has made its way into the classroom. More and more educators are utilizing technological resources in creative ways with the intent to enhance learning, including using virtual laboratories in the sciences in place of the "traditional" science laboratories. This has generated much discussion as to the influence on student achievement when online learning replaces the face-to-face contact between instructor and student. The purpose of this study was to discern differences in achievement of two laboratory instruction types: virtual laboratory and a traditional laboratory. Results of this study indicate statistical significant differences in student achievement defined by averages on quiz scores in virtual labs compared with traditional face-to-face laboratories and traditional laboratories result in greater student learning gains than virtual labs. Lecture exam averages were also greater for students enrolled in the traditional laboratories compared to students enrolled in the virtual laboratories. To account for possible differences in ability among students, a potential extraneous variable, GPA and ACT scores were used as covariates.

Optimized distributed systems achieve significant performance improvement on sorted merging of massive VCF files.

PubMed

Sun, Xiaobo; Gao, Jingjing; Jin, Peng; Eng, Celeste; Burchard, Esteban G; Beaty, Terri H; Ruczinski, Ingo; Mathias, Rasika A; Barnes, Kathleen; Wang, Fusheng; Qin, Zhaohui S

2018-06-01

Sorted merging of genomic data is a common data operation necessary in many sequencing-based studies. It involves sorting and merging genomic data from different subjects by their genomic locations. In particular, merging a large number of variant call format (VCF) files is frequently required in large-scale whole-genome sequencing or whole-exome sequencing projects. Traditional single-machine based methods become increasingly inefficient when processing large numbers of files due to the excessive computation time and Input/Output bottleneck. Distributed systems and more recent cloud-based systems offer an attractive solution. However, carefully designed and optimized workflow patterns and execution plans (schemas) are required to take full advantage of the increased computing power while overcoming bottlenecks to achieve high performance. In this study, we custom-design optimized schemas for three Apache big data platforms, Hadoop (MapReduce), HBase, and Spark, to perform sorted merging of a large number of VCF files. These schemas all adopt the divide-and-conquer strategy to split the merging job into sequential phases/stages consisting of subtasks that are conquered in an ordered, parallel, and bottleneck-free way. In two illustrating examples, we test the performance of our schemas on merging multiple VCF files into either a single TPED or a single VCF file, which are benchmarked with the traditional single/parallel multiway-merge methods, message passing interface (MPI)-based high-performance computing (HPC) implementation, and the popular VCFTools. Our experiments suggest all three schemas either deliver a significant improvement in efficiency or render much better strong and weak scalabilities over traditional methods. Our findings provide generalized scalable schemas for performing sorted merging on genetics and genomics data using these Apache distributed systems.

When is Chemical Similarity Significant? The Statistical Distribution of Chemical Similarity Scores and Its Extreme Values

PubMed Central

Baldi, Pierre

2010-01-01

As repositories of chemical molecules continue to expand and become more open, it becomes increasingly important to develop tools to search them efficiently and assess the statistical significance of chemical similarity scores. Here we develop a general framework for understanding, modeling, predicting, and approximating the distribution of chemical similarity scores and its extreme values in large databases. The framework can be applied to different chemical representations and similarity measures but is demonstrated here using the most common binary fingerprints with the Tanimoto similarity measure. After introducing several probabilistic models of fingerprints, including the Conditional Gaussian Uniform model, we show that the distribution of Tanimoto scores can be approximated by the distribution of the ratio of two correlated Normal random variables associated with the corresponding unions and intersections. This remains true also when the distribution of similarity scores is conditioned on the size of the query molecules in order to derive more fine-grained results and improve chemical retrieval. The corresponding extreme value distributions for the maximum scores are approximated by Weibull distributions. From these various distributions and their analytical forms, Z-scores, E-values, and p-values are derived to assess the significance of similarity scores. In addition, the framework allows one to predict also the value of standard chemical retrieval metrics, such as Sensitivity and Specificity at fixed thresholds, or ROC (Receiver Operating Characteristic) curves at multiple thresholds, and to detect outliers in the form of atypical molecules. Numerous and diverse experiments carried in part with large sets of molecules from the ChemDB show remarkable agreement between theory and empirical results. PMID:20540577

Measuring the Success of an Academic Development Programme: A Statistical Analysis

ERIC Educational Resources Information Center

Smith, L. C.

2009-01-01

This study uses statistical analysis to estimate the impact of first-year academic development courses in microeconomics, statistics, accountancy, and information systems, offered by the University of Cape Town's Commerce Academic Development Programme, on students' graduation performance relative to that achieved by mainstream students. The data…

Assessing Attitudes towards Statistics among Medical Students: Psychometric Properties of the Serbian Version of the Survey of Attitudes Towards Statistics (SATS)

PubMed Central

Stanisavljevic, Dejana; Trajkovic, Goran; Marinkovic, Jelena; Bukumiric, Zoran; Cirkovic, Andja; Milic, Natasa

2014-01-01

Background Medical statistics has become important and relevant for future doctors, enabling them to practice evidence based medicine. Recent studies report that students’ attitudes towards statistics play an important role in their statistics achievements. The aim of the study was to test the psychometric properties of the Serbian version of the Survey of Attitudes Towards Statistics (SATS) in order to acquire a valid instrument to measure attitudes inside the Serbian educational context. Methods The validation study was performed on a cohort of 417 medical students who were enrolled in an obligatory introductory statistics course. The SATS adaptation was based on an internationally accepted methodology for translation and cultural adaptation. Psychometric properties of the Serbian version of the SATS were analyzed through the examination of factorial structure and internal consistency. Results Most medical students held positive attitudes towards statistics. The average total SATS score was above neutral (4.3±0.8), and varied from 1.9 to 6.2. Confirmatory factor analysis validated the six-factor structure of the questionnaire (Affect, Cognitive Competence, Value, Difficulty, Interest and Effort). Values for fit indices TLI (0.940) and CFI (0.961) were above the cut-off of ≥0.90. The RMSEA value of 0.064 (0.051–0.078) was below the suggested value of ≤0.08. Cronbach’s alpha of the entire scale was 0.90, indicating scale reliability. In a multivariate regression model, self-rating of ability in mathematics and current grade point average were significantly associated with the total SATS score after adjusting for age and gender. Conclusion Present study provided the evidence for the appropriate metric properties of the Serbian version of SATS. Confirmatory factor analysis validated the six-factor structure of the scale. The SATS might be reliable and a valid instrument for identifying medical students’ attitudes towards statistics in the Serbian

Back to the basics: Identifying and addressing underlying challenges in achieving high quality and relevant health statistics for indigenous populations in Canada

PubMed Central

Smylie, Janet; Firestone, Michelle

2015-01-01

Canada is known internationally for excellence in both the quality and public policy relevance of its health and social statistics. There is a double standard however with respect to the relevance and quality of statistics for Indigenous populations in Canada. Indigenous specific health and social statistics gathering is informed by unique ethical, rights-based, policy and practice imperatives regarding the need for Indigenous participation and leadership in Indigenous data processes throughout the spectrum of indicator development, data collection, management, analysis and use. We demonstrate how current Indigenous data quality challenges including misclassification errors and non-response bias systematically contribute to a significant underestimate of inequities in health determinants, health status, and health care access between Indigenous and non-Indigenous people in Canada. The major quality challenge underlying these errors and biases is the lack of Indigenous specific identifiers that are consistent and relevant in major health and social data sources. The recent removal of an Indigenous identity question from the Canadian census has resulted in further deterioration of an already suboptimal system. A revision of core health data sources to include relevant, consistent, and inclusive Indigenous self-identification is urgently required. These changes need to be carried out in partnership with Indigenous peoples and their representative and governing organizations. PMID:26793283

A model for indexing medical documents combining statistical and symbolic knowledge.

PubMed

Avillach, Paul; Joubert, Michel; Fieschi, Marius

2007-10-11

To develop and evaluate an information processing method based on terminologies, in order to index medical documents in any given documentary context. We designed a model using both symbolic general knowledge extracted from the Unified Medical Language System (UMLS) and statistical knowledge extracted from a domain of application. Using statistical knowledge allowed us to contextualize the general knowledge for every particular situation. For each document studied, the extracted terms are ranked to highlight the most significant ones. The model was tested on a set of 17,079 French standardized discharge summaries (SDSs). The most important ICD-10 term of each SDS was ranked 1st or 2nd by the method in nearly 90% of the cases. The use of several terminologies leads to more precise indexing. The improvement achieved in the models implementation performances as a result of using semantic relationships is encouraging.

A Model for Indexing Medical Documents Combining Statistical and Symbolic Knowledge.

PubMed Central

Avillach, Paul; Joubert, Michel; Fieschi, Marius

2007-01-01

OBJECTIVES: To develop and evaluate an information processing method based on terminologies, in order to index medical documents in any given documentary context. METHODS: We designed a model using both symbolic general knowledge extracted from the Unified Medical Language System (UMLS) and statistical knowledge extracted from a domain of application. Using statistical knowledge allowed us to contextualize the general knowledge for every particular situation. For each document studied, the extracted terms are ranked to highlight the most significant ones. The model was tested on a set of 17,079 French standardized discharge summaries (SDSs). RESULTS: The most important ICD-10 term of each SDS was ranked 1st or 2nd by the method in nearly 90% of the cases. CONCLUSIONS: The use of several terminologies leads to more precise indexing. The improvement achieved in the model’s implementation performances as a result of using semantic relationships is encouraging. PMID:18693792

Meteor trail footprint statistics

NASA Astrophysics Data System (ADS)

Mui, S. Y.; Ellicott, R. C.

Footprint statistics derived from field-test data are presented. The statistics are the probability that two receivers will lie in the same footprint. The dependence of the footprint statistics on the transmitter range, link orientation, and antenna polarization are examined. Empirical expressions for the footprint statistics are presented. The need to distinguish the instantaneous footprint, which is the area illuminated at a particular instant, from the composite footprint, which is the total area illuminated during the lifetime of the meteor trail, is explained. The statistics for the instantaneous and composite footprints have been found to be similar. The only significant difference lies in the parameter that represents the probability of two colocated receivers being in the same footprint. The composite footprint statistics can be used to calculate the space diversity gain of a multiple-receiver system. The instantaneous footprint statistics are useful in the evaluation of the interference probability in a network of meteor burst communication nodes.

The Relationship between Family Functioning and Academic Achievement in Female High School Students of Isfahan, Iran, in 2013-2014.

PubMed

Rezaei-Dehaghani, Abdollah; Keshvari, Mahrokh; Paki, Somayeh

2018-01-01

Nowadays, the most important problem of the educational system is the vast spread of school failure. Therefore, detection of the factors leading to or preventing students' academic achievement is of utmost importance. Family function is considered to be a critical component of academic success. This study aimed to investigate the relationship between family functioning and academic achievement in high school female students in Isfahan. This descriptive correlational study was conducted through random sampling among 237 female high school students in Isfahan during school year 2013-2014. Data were collected by participants' personal characteristics and Bloom family function questionnaires. To analyze the data, descriptive statistics (mean and standard deviation) and inferential statistics (Pearson correlation and linear regression analysis) were adopted and computed using SPSS software. The results showed a significant correlation between family function (except lack of independence) and students' academic achievement ( p < 0.05). Further, among family function dimensions, expressiveness ( β = 0.235, p < 0.001), family socialization ( β = 0.219, p = 0.001), and cohesion ( β = 0.211, p = 0.001) were more reliable predictors of academic achievement. The results of this study showed that students' academic achievement is highly correlated with the performance of their families. Therefore, to improve students' educational status in cultural and educational programs, which are specified for them, family function centered plans should be at the heart of attention.

Academic Achievement in Physics-Chemistry: The Predictive Effect of Attitudes and Reasoning Abilities.

PubMed

Vilia, Paulo N; Candeias, Adelinda A; Neto, António S; Franco, Maria Da Glória S; Melo, Madalena

2017-01-01

Science education plays a critical role as political priority due to its fundamental importance in engaging students to pursue technological careers considered essential in modern societies, in order to face scientific development challenges. High-level achievement on science education and positive attitudes toward science constitutes a crucial challenge for formal education. Several studies indicate close relationships between students' attitudes, cognitive abilities, and academic achievement. The main purpose of this study is to analyze the impact of student's attitudes toward the school discipline of Physics and Chemistry and their reasoning abilities on academic achievement on that school subject, among Portuguese 9th grade students using the data collected during the Project Academic Performance and Development: a longitudinal study on the effects of school transitions in Portuguese students (PTDC/CPE-CED/104884/2008). The participants were 470 students (267 girls - 56.8% and 203 boys - 43.2%), aged 14-16 years old (μ = 14.3 ± 0.58). The attitude data were collected using the Attitude toward Physics-Chemistry Questionnaire (ATPCQ) and, the Reasoning Test Battery (RTB) was used to assess the students reasoning abilities. Achievement was measured using the students' quarterly (9-week) grades in the physics and chemistry subject. The relationships between the attitude dimensions toward Physics-chemistry and the reasoning dimensions and achievement in each of the three school terms were assessed by multiple regression stepwise analyses and standardized regression coefficients (β), calculated with IBM SPSS Statistics 21 software. Both variables studied proved to be significant predictor variables of school achievement. The models obtained from the use of both variables were always stronger accounting for higher proportions of student's grade variations. The results show that ATPCQ and RTB had a significantly positive relationship with student's achievement in

A Comparison of Students in Single-Sex Classes and Coeducational Classes in High Poverty Public Elementary Schools in Mathematics and Reading Achievement

ERIC Educational Resources Information Center

Aldridge, Ashley Elizabeth

2009-01-01

The purpose of this study was to investigate whether any statistically significant differences in mathematics and reading academic achievement and academic gains of male and female students taught in single-sex classes existed when compared to male and female students taught in coeducational classes. This study reported findings from mathematics…

A Modified Moore Approach to Teaching Mathematical Statistics: An Inquiry Based Learning Technique to Teaching Mathematical Statistics

ERIC Educational Resources Information Center

McLoughlin, M. Padraig M. M.

2008-01-01

The author of this paper submits the thesis that learning requires doing; only through inquiry is learning achieved, and hence this paper proposes a programme of use of a modified Moore method in a Probability and Mathematical Statistics (PAMS) course sequence to teach students PAMS. Furthermore, the author of this paper opines that set theory…

Superordinate Shape Classification Using Natural Shape Statistics

ERIC Educational Resources Information Center

Wilder, John; Feldman, Jacob; Singh, Manish

2011-01-01

This paper investigates the classification of shapes into broad natural categories such as "animal" or "leaf". We asked whether such coarse classifications can be achieved by a simple statistical classification of the shape skeleton. We surveyed databases of natural shapes, extracting shape skeletons and tabulating their…

Statistical lamb wave localization based on extreme value theory

NASA Astrophysics Data System (ADS)

Harley, Joel B.

2018-04-01

Guided wave localization methods based on delay-and-sum imaging, matched field processing, and other techniques have been designed and researched to create images that locate and describe structural damage. The maximum value of these images typically represent an estimated damage location. Yet, it is often unclear if this maximum value, or any other value in the image, is a statistically significant indicator of damage. Furthermore, there are currently few, if any, approaches to assess the statistical significance of guided wave localization images. As a result, we present statistical delay-and-sum and statistical matched field processing localization methods to create statistically significant images of damage. Our framework uses constant rate of false alarm statistics and extreme value theory to detect damage with little prior information. We demonstrate our methods with in situ guided wave data from an aluminum plate to detect two 0.75 cm diameter holes. Our results show an expected improvement in statistical significance as the number of sensors increase. With seventeen sensors, both methods successfully detect damage with statistical significance.

Perceived School and Neighborhood Safety, Neighborhood Violence and Academic Achievement in Urban School Children

PubMed Central

AJ, Milam; CDM, Furr-Holden; PJ, Leaf

2010-01-01

Community and school violence continue to be a major public health problem, especially among urban children and adolescents. Little research has focused on the effect of school safety and neighborhood violence on academic performance. This study examines the effect of the school and neighborhood climate on academic achievement among a population of 3rd-5th grade students in an urban public school system. Community and school safety were assessed using the School Climate Survey, an annual city-wide assessment of student’s perception of school and community safety. Community violence was measured using the Neighborhood Inventory for Environmental Typology, an objective observational assessment of neighborhood characteristics. Academic achievement was measured using the Maryland State Assessment (MSA), a standardized exam given to all Maryland 3rd-8th graders. School Climate Data and MSA data were aggregated by school and grade. Objective assessments of neighborhood environment and students’ self-reported school and neighborhood safety were both strongly associated with academic performance. Increasing neighborhood violence was associated with statistically significant decreases from 4.2%-8.7% in math and reading achievement; increasing perceived safety was associated with significant increases in achievement from 16%-22%. These preliminary findings highlight the adverse impact of perceived safety and community violence exposure on primary school children’s academic performance. PMID:21197388

A Quasi-Experimental Study on Using Short Stories: Statistical and Inferential Analyses on the Non-English Major University Students' Speaking and Writing Achievements

ERIC Educational Resources Information Center

Iman, Jaya Nur

2017-01-01

This research was conducted to find out whether or not using short stories significantly improve the speaking and writing achievements. A quasi-experimental study of non-equivalent pretest-posttest control group design or comparison group design was used in this research. The population of this research was the all first semester undergraduate…

Use of response surface methodology in a fed-batch process for optimization of tricarboxylic acid cycle intermediates to achieve high levels of canthaxanthin from Dietzia natronolimnaea HS-1.

PubMed

Nasri Nasrabadi, Mohammad Reza; Razavi, Seyed Hadi

2010-04-01

In this work, we applied statistical experimental design to a fed-batch process for optimization of tricarboxylic acid cycle (TCA) intermediates in order to achieve high-level production of canthaxanthin from Dietzia natronolimnaea HS-1 cultured in beet molasses. A fractional factorial design (screening test) was first conducted on five TCA cycle intermediates. Out of the five TCA cycle intermediates investigated via screening tests, alfaketoglutarate, oxaloacetate and succinate were selected based on their statistically significant (P<0.05) and positive effects on canthaxanthin production. These significant factors were optimized by means of response surface methodology (RSM) in order to achieve high-level production of canthaxanthin. The experimental results of the RSM were fitted with a second-order polynomial equation by means of a multiple regression technique to identify the relationship between canthaxanthin production and the three TCA cycle intermediates. By means of this statistical design under a fed-batch process, the optimum conditions required to achieve the highest level of canthaxanthin (13172 + or - 25 microg l(-1)) were determined as follows: alfaketoglutarate, 9.69 mM; oxaloacetate, 8.68 mM; succinate, 8.51 mM. Copyright 2009 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Perceptions of Relatedness with Classroom Peers Promote Adolescents’ Behavioral Engagement and Achievement in Secondary School

PubMed Central

Mikami, Amori Yee; Ruzek, Erik A.; Hafen, Christopher A.; Gregory, Anne; Allen, Joseph P.

2017-01-01

Secondary school is a vulnerable time where stagnation or declines in classroom behavioral engagement occur for many students, and peer relationships take on a heightened significance. We examined the implications of adolescents’ perceptions of relatedness with classroom peers for their academic learning. Participants were 1084 adolescents (53% female) in 65 middle and high school classrooms. Multilevel cross-lagged path analyses found that adolescents’ perceived relatedness with classroom peers subsequently predicted their increased self-reported behavioral engagement in that classroom from fall to winter and again from winter to spring. Higher engagement in spring predicted higher end of year objective achievement test scores after statistical control of prior year test scores. Implications are discussed for increasing classroom peer relatedness to enhance adolescents’ achievement. PMID:28755252

Marital Adjustment and Children's Academic Achievement.

ERIC Educational Resources Information Center

Westerman, Michael A.; La Luz, Edgar J.

1995-01-01

Investigated the relationship between marital adjustment and children's functioning at school and home. Marital adjustment was significantly related to two achievement measures (grades and teacher reports of school performance) and a trend was found for a third (achievement test scores). Significant associations also were found for other measures…

The impact of teacher preparation on student achievement in rural secondary schools

NASA Astrophysics Data System (ADS)

Barnes, Shontier Prescott

The primary purpose of this study was to examine significant differences, if any, in student achievement in the area of math and science of students taught by traditionally certified teachers and alternatively certified teachers. This study examined alternatively certified teachers, as identified from through the Georgia TAPP (Teacher Alternative Preparation Program), and traditionally certified teachers in rural high schools in the Central Savannah River Area of Georgia. Student achievement was measured by student scores on the Algebra I and Physical Science End-Of-Course Test, a criterion-referenced test aligned with state adopted curriculum standards. The study utilized frequency distributions, correlations, descriptive statistics, and univariate analysis of variance (ANOVA) to examine the data. Univariate tests were done to find individual differences for each dependent variable. The ANOVA was used for the single dependent (student achievement) and formed comparisons and tracked the effect of the independent variable (teacher preparation), each of which (traditional and alternative) may have a number of levels and may interact to affect the dependent variable. The covariates, the independent variables not manipulated, but still affecting the response, are students' ethnicity, gender, and school socioeconomic status were also analyzed to predict student achievement. KEY WORDS. Teacher Preparation, Student Achievement, Math, Science, Traditionally certified teachers, Alternatively certified teachers, Georgia TAPP (Teacher Alternative Preparation Program), End-Of-Course Test (EOCT), Performance standard.

Aberrant Learning Achievement Detection Based on Person-Fit Statistics in Personalized e-Learning Systems

ERIC Educational Resources Information Center

Liu, Ming-Tsung; Yu, Pao-Ta

2011-01-01

A personalized e-learning service provides learning content to fit learners' individual differences. Learning achievements are influenced by cognitive as well as non-cognitive factors such as mood, motivation, interest, and personal styles. This paper proposes the Learning Caution Indexes (LCI) to detect aberrant learning patterns. The philosophy…

Optimized distributed systems achieve significant performance improvement on sorted merging of massive VCF files

PubMed Central

Gao, Jingjing; Jin, Peng; Eng, Celeste; Burchard, Esteban G; Beaty, Terri H; Ruczinski, Ingo; Mathias, Rasika A; Barnes, Kathleen; Wang, Fusheng

2018-01-01

Abstract Background Sorted merging of genomic data is a common data operation necessary in many sequencing-based studies. It involves sorting and merging genomic data from different subjects by their genomic locations. In particular, merging a large number of variant call format (VCF) files is frequently required in large-scale whole-genome sequencing or whole-exome sequencing projects. Traditional single-machine based methods become increasingly inefficient when processing large numbers of files due to the excessive computation time and Input/Output bottleneck. Distributed systems and more recent cloud-based systems offer an attractive solution. However, carefully designed and optimized workflow patterns and execution plans (schemas) are required to take full advantage of the increased computing power while overcoming bottlenecks to achieve high performance. Findings In this study, we custom-design optimized schemas for three Apache big data platforms, Hadoop (MapReduce), HBase, and Spark, to perform sorted merging of a large number of VCF files. These schemas all adopt the divide-and-conquer strategy to split the merging job into sequential phases/stages consisting of subtasks that are conquered in an ordered, parallel, and bottleneck-free way. In two illustrating examples, we test the performance of our schemas on merging multiple VCF files into either a single TPED or a single VCF file, which are benchmarked with the traditional single/parallel multiway-merge methods, message passing interface (MPI)–based high-performance computing (HPC) implementation, and the popular VCFTools. Conclusions Our experiments suggest all three schemas either deliver a significant improvement in efficiency or render much better strong and weak scalabilities over traditional methods. Our findings provide generalized scalable schemas for performing sorted merging on genetics and genomics data using these Apache distributed systems. PMID:29762754

Achievement and Underachievement: The Experiences of African Caribbeans

ERIC Educational Resources Information Center

Rhamie, Jasmine

2012-01-01

The disproportionate representation of African Caribbeans in all the negative educational statistics has been well documented. Despite this, there are African Caribbeans who achieve academically but relatively few studies have explored this area. This study aimed to investigate the factors that contribute to African Caribbean academic success,…

Connecting Principal Leadership, Teacher Collaboration, and Student Achievement

ERIC Educational Resources Information Center

Goddard, Yvonne L.; Miller, Robert; Larsen, Ross; Goddard, Roger; Madsen, Jean; Schroeder, Patricia

2010-01-01

The purpose of this paper was to test the relationship between principal leadership and teacher collaboration around instructional improvement to determine whether these measures were statistically related and whether, together, they were associated with academic achievement in elementary schools. Data were obtained from 1,600 teachers in 96…

Cognitive ability, academic achievement and academic self-concept: extending the internal/external frame of reference model.

PubMed

Chen, Ssu-Kuang; Hwang, Fang-Ming; Yeh, Yu-Chen; Lin, Sunny S J

2012-06-01

Marsh's internal/external (I/E) frame of reference model depicts the relationship between achievement and self-concept in specific academic domains. Few efforts have been made to examine concurrent relationships among cognitive ability, achievement, and academic self-concept (ASC) within an I/E model framework. To simultaneously examine the influences of domain-specific cognitive ability and grades on domain self-concept in an extended I/E model, including the indirect effect of domain-specific cognitive ability on domain self-concept via grades. Tenth grade respondents (628 male, 452 female) to a national adolescent survey conducted in Taiwan. Respondents completed surveys designed to measure maths and verbal aptitudes. Data on Maths and Chinese class grades and self-concepts were also collected. Statistically significant and positive path coefficients were found between cognitive ability and self-concept in the same domain (direct effect) and between these two constructs via grades (indirect effect). The cross-domain effects of either ability or grades on ASC were negatively significant. Taiwanese 10th graders tend to evaluate their ASCs based on a mix of ability and achievement, with achievement as a mediator exceeding ability as a predictor. In addition, the cross-domain effects suggest that Taiwanese students are likely to view Maths and verbal abilities and achievements as distinctly different. ©2011 The British Psychological Society.

The Computer Student Worksheet Based Mathematical Literacy for Statistics

NASA Astrophysics Data System (ADS)

Manoy, J. T.; Indarasati, N. A.

2018-01-01

The student worksheet is one of media teaching which is able to improve teaching an activity in the classroom. Indicators in mathematical literacy were included in a student worksheet is able to help the students for applying the concept in daily life. Then, the use of computers in learning can create learning with environment-friendly. This research used developmental research which was Thiagarajan (Four-D) development design. There are 4 stages in the Four-D, define, design, develop, and disseminate. However, this research was finish until the third stage, develop stage. The computer student worksheet based mathematical literacy for statistics executed good quality. This student worksheet is achieving the criteria if able to achieve three aspects, validity, practicality, and effectiveness. The subject in this research was the students at The 1st State Senior High School of Driyorejo, Gresik, grade eleven of The 5th Mathematics and Natural Sciences. The computer student worksheet products based mathematical literacy for statistics executed good quality, while it achieved the aspects for validity, practical, and effectiveness. This student worksheet achieved the validity aspects with an average of 3.79 (94.72%), and practical aspects with an average of 2.85 (71.43%). Besides, it achieved the effectiveness aspects with a percentage of the classical complete students of 94.74% and a percentage of the student positive response of 75%.

Correlations among Six Learner Variables and the Performance of a Sample of Jamaican Eleventh-Graders on an Achievement Test on Respiration

ERIC Educational Resources Information Center

Soyibo, Kola; Pinnock, Jacqueline

2005-01-01

This study aimed at establishing if the level of performance of 500 Jamaican Grade 11 students on an achievement test on the concept of respiration was satisfactory (mean = 28 or 70% and above) or not (less than 70%); if there were statistically significant differences in their performance on the concept linked to their gender, cognitive abilities…

A Technology-Based Statistical Reasoning Assessment Tool in Descriptive Statistics for Secondary School Students

ERIC Educational Resources Information Center

Chan, Shiau Wei; Ismail, Zaleha

2014-01-01

The focus of assessment in statistics has gradually shifted from traditional assessment towards alternative assessment where more attention has been paid to the core statistical concepts such as center, variability, and distribution. In spite of this, there are comparatively few assessments that combine the significant three types of statistical…

How to read a paper. Statistics for the non-statistician. II: "Significant" relations and their pitfalls.

PubMed

Greenhalgh, T

1997-08-16

It is possible to be seriously misled by taking the statistical competence (and/or the intellectual honesty) of authors for granted. Some common errors committed (deliberately or inadvertently) by the authors of papers are given in the final box.

Fostering Self-Concept and Interest for Statistics through Specific Learning Environments

ERIC Educational Resources Information Center

Sproesser, Ute; Engel, Joachim; Kuntze, Sebastian

2016-01-01

Supporting motivational variables such as self-concept or interest is an important goal of schooling as they relate to learning and achievement. In this study, we investigated whether specific interest and self-concept related to the domains of statistics and mathematics can be fostered through a four-lesson intervention focusing on statistics.…

The effect of an integrated high school science curriculum on student achievement, knowledge retention, and science attitudes

NASA Astrophysics Data System (ADS)

Smith, Kimberly A.

The research study investigates the effectiveness of an integrated high school science curriculum on student achievement, knowledge retention and science attitudes using quantitative and qualitative research. Data was collected from tenth grade students, in a small urban high school in Kansas City, Missouri, who were enrolled in a traditional Biology course or an integrated Environmental Science course. Quantitative data was collected in Phase 1 of the study. Data collected for academic achievement included pretest and posttest scores on the CTBS MATN exam. Data collected for knowledge retention included post-posttest scores on the CTBS MATN exam. Data collected for science attitudes were scores on a pretest and posttest using the TOSRA. SPSS was used to analyze the data using independent samples t-tests, one-way ANCOVA's and paired samples statistics. Qualitative data was collected in Phase 2 of the study. Data included responses to open-ended interview questions using three focus groups. Data was analyzed for common themes. Data analysis revealed the integrated Environmental Science course had a statistically significant impact on academic achievement, knowledge retention and positive science attitudes. Gender and socioeconomic status did not influence results. The study also determined that the CTBS MATN exam was not an accurate predictor of scores on state testing as was previously thought.

Experimental assessment of oral hygiene achieved by children wearing rapid palatal expanders, comparing manual and electric toothbrushes.

PubMed

Mazzoleni, S; Bonaldo, G; Pontarolo, E; Zuccon, A; De Francesco, M; Stellini, E

2014-08-01

The aim was to compare the efficacy of the electric versus the manual toothbrush in terms of the oral hygiene achieved by patients wearing rapid palatal expanders (RPEs). Forty patients were randomly divided into two groups; one equipped with a manual toothbrush (Group A), the other with an electric toothbrush (Group B). Each child's plaque index (PI) and gingival index (GI) were calculated at banded molar level at times T0 (before banding), T1 (a month later), T2 (3 months later) and T3 (when the expander was removed). At each appointment, the PI and GI were recorded and the patient was remotivated. The level of oral hygiene achieved by the group using an electric toothbrush produced a greater improvement in the two indexes than in the group using the manual toothbrush that showed no statistically significant improvement (PI T0-T3: P = 0.309; GI T0-T3: P = 0.141). Both indexes dropped considerably in both groups from T0 to T2, but more so in the group B. From T2 to T3, although the electric toothbrush continued to be substantially more effective, Group B showed a statistically significant deterioration in the oral hygiene (PI +20%; GI +33%). Other assessments conducted on particular areas of the tooth showed improvements in the PI (-33%) for the vestibular region, and for the GI (-57%) in the palatal region among the patients in Group B, while there were no significant changes in these indexes in Group A. Our findings show that the electric toothbrush is statistically more efficient in performing an adequate level of oral hygiene in children wearing RPE. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

How to read a paper. Statistics for the non-statistician. II: "Significant" relations and their pitfalls.

PubMed Central

Greenhalgh, T.

1997-01-01

It is possible to be seriously misled by taking the statistical competence (and/or the intellectual honesty) of authors for granted. Some common errors committed (deliberately or inadvertently) by the authors of papers are given in the final box. PMID:9277611

Statistical atlas based extrapolation of CT data

NASA Astrophysics Data System (ADS)

Chintalapani, Gouthami; Murphy, Ryan; Armiger, Robert S.; Lepisto, Jyri; Otake, Yoshito; Sugano, Nobuhiko; Taylor, Russell H.; Armand, Mehran

2010-02-01

We present a framework to estimate the missing anatomical details from a partial CT scan with the help of statistical shape models. The motivating application is periacetabular osteotomy (PAO), a technique for treating developmental hip dysplasia, an abnormal condition of the hip socket that, if untreated, may lead to osteoarthritis. The common goals of PAO are to reduce pain, joint subluxation and improve contact pressure distribution by increasing the coverage of the femoral head by the hip socket. While current diagnosis and planning is based on radiological measurements, because of significant structural variations in dysplastic hips, a computer-assisted geometrical and biomechanical planning based on CT data is desirable to help the surgeon achieve optimal joint realignments. Most of the patients undergoing PAO are young females, hence it is usually desirable to minimize the radiation dose by scanning only the joint portion of the hip anatomy. These partial scans, however, do not provide enough information for biomechanical analysis due to missing iliac region. A statistical shape model of full pelvis anatomy is constructed from a database of CT scans. The partial volume is first aligned with the statistical atlas using an iterative affine registration, followed by a deformable registration step and the missing information is inferred from the atlas. The atlas inferences are further enhanced by the use of X-ray images of the patient, which are very common in an osteotomy procedure. The proposed method is validated with a leave-one-out analysis method. Osteotomy cuts are simulated and the effect of atlas predicted models on the actual procedure is evaluated.

Parenting Style and Parental Involvement: Relations with Adolescent Achievement.

ERIC Educational Resources Information Center

Paulson, Sharon E.

1994-01-01

Eighty ninth-grade students completed questionnaires regarding their parents' demandingness, responsiveness, school involvement, and commitment to achievement. Boys' reports of both maternal and paternal parenting significantly predicted their achievement, with parental values toward achievement significantly predicting achievement in boys above…

Statistical iterative reconstruction to improve image quality for digital breast tomosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Shiyu, E-mail: shiyu.xu@gmail.com; Chen, Ying, E-mail: adachen@siu.edu; Lu, Jianping

2015-09-15

Purpose: Digital breast tomosynthesis (DBT) is a novel modality with the potential to improve early detection of breast cancer by providing three-dimensional (3D) imaging with a low radiation dose. 3D image reconstruction presents some challenges: cone-beam and flat-panel geometry, and highly incomplete sampling. A promising means to overcome these challenges is statistical iterative reconstruction (IR), since it provides the flexibility of accurate physics modeling and a general description of system geometry. The authors’ goal was to develop techniques for applying statistical IR to tomosynthesis imaging data. Methods: These techniques include the following: a physics model with a local voxel-pair basedmore » prior with flexible parameters to fine-tune image quality; a precomputed parameter λ in the prior, to remove data dependence and to achieve a uniform resolution property; an effective ray-driven technique to compute the forward and backprojection; and an oversampled, ray-driven method to perform high resolution reconstruction with a practical region-of-interest technique. To assess the performance of these techniques, the authors acquired phantom data on the stationary DBT prototype system. To solve the estimation problem, the authors proposed an optimization-transfer based algorithm framework that potentially allows fewer iterations to achieve an acceptably converged reconstruction. Results: IR improved the detectability of low-contrast and small microcalcifications, reduced cross-plane artifacts, improved spatial resolution, and lowered noise in reconstructed images. Conclusions: Although the computational load remains a significant challenge for practical development, the superior image quality provided by statistical IR, combined with advancing computational techniques, may bring benefits to screening, diagnostics, and intraoperative imaging in clinical applications.« less

First Generation College Students: Motivation, Integration, and Academic Achievement

ERIC Educational Resources Information Center

Prospero, Moises; Vohra-Gupta, Shetal

2007-01-01

The study reported in this article investigated motivation and integration dimensions that influence college academic achievement of first-generation students compared to nonfirst-generation students. Participants consisted of 277 ethnically diverse students who were attending a community college. Bivariate and multivariate statistical analyses…

Do Algorithms Homogenize Students' Achievements in Secondary School Better than Teachers' Tracking Decisions?

ERIC Educational Resources Information Center

Klapproth, Florian

2015-01-01

Two objectives guided this research. First, this study examined how well teachers' tracking decisions contribute to the homogenization of their students' achievements. Second, the study explored whether teachers' tracking decisions would be outperformed in homogenizing the students' achievements by statistical models of tracking decisions. These…

School Vouchers and Student Achievement: Recent Evidence, Remaining Questions. WP 2008-08

ERIC Educational Resources Information Center

Rouse, Cecilia Elena; Barrow, Lisa

2008-01-01

In this article, we review the empirical evidence on the impact of education vouchers on student achievement, and briefly discuss the evidence from other forms of school choice. The best research to date finds relatively small achievement gains for students offered education vouchers, most of which are not statistically different from zero.…

Academic achievement and primary care specialty selection of volunteers at a student-run free clinic.

PubMed

Vaikunth, Sumeet S; Cesari, Whitney A; Norwood, Kimberlee V; Satterfield, Suzanne; Shreve, Robert G; Ryan, J Patrick; Lewis, James B

2014-01-01

Previous studies have reached conflicting conclusions about the associations between service and academic achievement and service and primary care specialty choice. This study examines the associations between service at a student-run clinic and academic achievement and primary care specialty choice. Retrospective review of medical student service and statistical analysis of grade point average (GPA), Step 1 and Step 2 Clinical Knowledge (CK) scores, and specialty choice were conducted, as approved by our Institutional Review Board. Volunteers, compared to nonvolunteers, had higher GPA (3.59 ± 0.33 vs. 3.40 ± 0.39, p < .001), Step 1 (229 ± 19 vs. 220 ± 21, p < .001), and Step 2 CK (240 ± 18 vs. 230 ± 21, p < .001) scores, but did not pursue primary care specialties at a significantly higher percentage (52% vs. 51%, χ² = .051, p = .82). Further exploration of the associations between service and academic achievement and primary care specialty choice is warranted.

Measuring the Effects of Peer Learning on Students' Academic Achievement in First-Year Business Statistics

ERIC Educational Resources Information Center

Dancer, Diane; Morrison, Kellie; Tarr, Garth

2015-01-01

Peer-assisted study session (PASS) programs have been shown to positively affect students' grades in a majority of studies. This study extends that analysis in two ways: controlling for ability and other factors, with focus on international students, and by presenting results for PASS in business statistics. Ordinary least squares, random effects…

Matching medical student achievement to learning objectives and outcomes: a paradigm shift for an implemented teaching module.

PubMed

Atta, Ihab Shafek; AlQahtani, Fahd Nasser

2018-01-01

Low student achievement in a basic imaging module was the impetus for an assessment of the module. A valid, reliable, and structured Likert scale was designed to measure the degree of student satisfaction with the domains of the module, including learning objectives (LO), teaching strategy and tools (TT), assessment tools (AT), and allotted credit hours (CH). Further analysis was conducted of student dissatisfaction to determine the subdomain in which module improvement was to be implemented. Statistical analysis of data among Likert scale domains was conducted. Likert scale data showed the TT domain to be the major reason for low student achievement. Statistical studies revealed 57/117 students (48.6%) were dissatisfied with TT, compared with LO 16/117 (13.6%), AT 54/117 (46.1%), and CH 12/117 (10.2%). Significant P -values were obtained for LO vs TT ( P <0.0001), LO vs AT ( P <0.0001), LO vs CH ( P <0.03), TT vs CH ( P <0.0001), and AT vs CH ( P <0.0001). No significant difference was observed between TT and AT ( P <0.29). Regarding TT, 41/117 (34.9%) students were dissatisfied with lectures (L) compared to hospital-based teaching (HPT) 24/117 (20%), problem-based learning (PBL) 8/117 (6.8%), self-directed learning (SDL) 3/117 (2.5%), and seminars (S) 4/117 (3.4%). Significant P -values were obtained for L vs HPT ( P <0.0001), L vs PBL ( P <0.0001), L vs SDL ( P <0.0001), L vs S ( P <0.0001), HPT vs PBL ( P <0.002), HPT vs SDL ( P <0.0001), and HPT vs S ( P <0.0001). Regarding lecture modifications, student satisfaction was 78.3% compared to 52% before modification. A significant P -value ( P <0.0001) was obtained between Likert scale domains before and after modification. Lecture modification resulted in a good student response and satisfaction. The major reason for low student achievement was the teaching tools, particularly the lectures. Major modifications to lectures improved student achievement. The students and most of the teaching staff were highly

HYPE: a WFD tool for the identification of significant and sustained upward trends in groundwater time series

NASA Astrophysics Data System (ADS)

Lopez, Benjamin; Croiset, Nolwenn; Laurence, Gourcy

2014-05-01

The Water Framework Directive 2006/11/CE (WFD) on the protection of groundwater against pollution and deterioration asks Member States to identify significant and sustained upward trends in all bodies or groups of bodies of groundwater that are characterised as being at risk in accordance with Annex II to Directive 2000/60/EC. The Directive indicates that the procedure for the identification of significant and sustained upward trends must be based on a statistical method. Moreover, for significant increases of concentrations of pollutants, trend reversals are identified as being necessary. This means to be able to identify significant trend reversals. A specific tool, named HYPE, has been developed in order to help stakeholders working on groundwater trend assessment. The R encoded tool HYPE provides statistical analysis of groundwater time series. It follows several studies on the relevancy of the use of statistical tests on groundwater data series (Lopez et al., 2011) and other case studies on the thematic (Bourgine et al., 2012). It integrates the most powerful and robust statistical tests for hydrogeological applications. HYPE is linked to the French national database on groundwater data (ADES). So monitoring data gathered by the Water Agencies can be directly processed. HYPE has two main modules: - a characterisation module, which allows to visualize time series. HYPE calculates the main statistical characteristics and provides graphical representations; - a trend module, which identifies significant breaks, trends and trend reversals in time series, providing result table and graphical representation (cf figure). Additional modules are also implemented to identify regional and seasonal trends and to sample time series in a relevant way. HYPE has been used successfully in 2012 by the French Water Agencies to satisfy requirements of the WFD, concerning characterization of groundwater bodies' qualitative status and evaluation of the risk of non-achievement of

Student achievement in science and mathematics on campuses that have implemented the CSCOPE curriculum model

NASA Astrophysics Data System (ADS)

Wilson, Emily R.

The purpose of this study was to determine whether differences in student achievement exist between school campuses which followed a specific standards-based curriculum model (CSCOPE) and school campuses which followed a non-CSCOPE or traditional curriculum model. One-hundred and sixty CSCOPE curriculum campuses and 160 non-CSCOPE curriculum campuses were used in the study. Achievement data were collected on students in the fifth, eighth, and eleventh grades using the campuses percentage passing on the Texas Assessment of Knowledge and Skills (TAKS) for both science and mathematics. The TAKS is the state-mandated assessment system used to comply with federal testing guidelines. Data for the 2007-2008 school year were used for the elementary level while data from 2006-2007 and 2007-2008 were used for junior high (middle school) and high school levels. Data were analyzed by overall class as well as aggregated by ethnic classifications. Descriptive statistics were used to summarize achievement results and t-tests were utilized to analyze achievement differences between the two curriculum models. Overall fifth grade students in CSCOPE schools outperformed (p < .05) non-CSCOPE counterparts in science and mathematics. Also, fifth grade Hispanic students using CSCOPE curriculum scored higher (p < .05) than those in traditional curricula. Eighth grade students in CSCOPE schools performed better (p < .05) in science than students in non-CSCOPE schools. Finally, eighth grade Hispanic and White subgroups using CSCOPE curriculum outperformed ( p < .05) their ethnic counterparts using traditional curriculum models. The only statistically significant finding at the eleventh grade level was the African-American subgroup in science, but this subgroup had too small of a sample to infer the findings to the population. Thus, the results would tend to support use of the standardized curriculum model (CSCOPE) at lower levels whereas achievement in high school may not be differentially

Why are hyperactivity and academic achievement related?

PubMed

Saudino, Kimberly J; Plomin, Robert

2007-01-01

Although a negative association between hyperactivity and academic achievement is well documented, little is known about the genetic and/or environmental mechanisms responsible for the association. The present study explored links between parent and teacher ratings of hyperactive behavior problems and teacher-assessed achievement in a sample of 1,876 twin pairs (mean age 7.04 years). The results did not differ across rater, nor were there significant differences between males or females or for twins in the same or different classrooms. Hyperactivity was significantly correlated with achievement. Multivariate model-fitting analyses revealed significant genetic and nonshared environmental covariance between the two phenotypes. In addition, bivariate heritabilities were substantial, indicating that the phenotypic correlations between hyperactivity and achievement were largely mediated by genetic influences.

Non-rigid image registration using a statistical spline deformation model.

PubMed

Loeckx, Dirk; Maes, Frederik; Vandermeulen, Dirk; Suetens, Paul

2003-07-01

We propose a statistical spline deformation model (SSDM) as a method to solve non-rigid image registration. Within this model, the deformation is expressed using a statistically trained B-spline deformation mesh. The model is trained by principal component analysis of a training set. This approach allows to reduce the number of degrees of freedom needed for non-rigid registration by only retaining the most significant modes of variation observed in the training set. User-defined transformation components, like affine modes, are merged with the principal components into a unified framework. Optimization proceeds along the transformation components rather then along the individual spline coefficients. The concept of SSDM's is applied to the temporal registration of thorax CR-images using pattern intensity as the registration measure. Our results show that, using 30 training pairs, a reduction of 33% is possible in the number of degrees of freedom without deterioration of the result. The same accuracy as without SSDM's is still achieved after a reduction up to 66% of the degrees of freedom.

Statistics Anxiety among Postgraduate Students

ERIC Educational Resources Information Center

Koh, Denise; Zawi, Mohd Khairi

2014-01-01

Most postgraduate programmes, that have research components, require students to take at least one course of research statistics. Not all postgraduate programmes are science based, there are a significant number of postgraduate students who are from the social sciences that will be taking statistics courses, as they try to complete their…

Statistics Using Just One Formula

ERIC Educational Resources Information Center

Rosenthal, Jeffrey S.

2018-01-01

This article advocates that introductory statistics be taught by basing all calculations on a single simple margin-of-error formula and deriving all of the standard introductory statistical concepts (confidence intervals, significance tests, comparisons of means and proportions, etc) from that one formula. It is argued that this approach will…

Do health and education agencies in the United States share responsibility for academic achievement and health? A review of 25 years of evidence about the relationship of adolescents' academic achievement and health behaviors.

PubMed

Bradley, Beverly J; Greene, Amy C

2013-05-01

The United States Centers for Disease Control and Prevention monitors health-risk behaviors of adolescents in United States, which include (1) violence; (2) tobacco use; (3) alcohol and other drug use; (4) sexual behaviors contributing to unintended pregnancy and sexually transmitted diseases; (5) inadequate physical activity; and (6) unhealthy dietary behaviors. We reviewed original research published in peer-reviewed journals between 1985 and 2010 to synthesize evidence about the association of adolescent health-risk behaviors and academic achievement. Using predetermined selection criteria, 122 articles were included that used at least one variable for health-risk behaviors and also for academic achievement. For all six health-risk behaviors, 96.6% of the studies reported statistically significant inverse relationships between health-risk behaviors and academic achievement. With this persuasive evidence about the interrelationship of health-risk behaviors and academic achievement, it is imperative that leaders in education and health act together to make wise investments in our nation's school-age youth that will benefit the entire population. A unified system that addresses both health behavior and academic achievement would have reciprocal and synergistic effects on the health and academic achievement not only of children and adolescents, but also of adults in the United States. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Addressing economic development goals through innovative teaching of university statistics: a case study of statistical modelling in Nigeria

NASA Astrophysics Data System (ADS)

Oseloka Ezepue, Patrick; Ojo, Adegbola

2012-12-01

A challenging problem in some developing countries such as Nigeria is inadequate training of students in effective problem solving using the core concepts of their disciplines. Related to this is a disconnection between their learning and socio-economic development agenda of a country. These problems are more vivid in statistical education which is dominated by textbook examples and unbalanced assessment 'for' and 'of' learning within traditional curricula. The problems impede the achievement of socio-economic development objectives such as those stated in the Nigerian Vision 2020 blueprint and United Nations Millennium Development Goals. They also impoverish the ability of (statistics) graduates to creatively use their knowledge in relevant business and industry sectors, thereby exacerbating mass graduate unemployment in Nigeria and similar developing countries. This article uses a case study in statistical modelling to discuss the nature of innovations in statistics education vital to producing new kinds of graduates who can link their learning to national economic development goals, create wealth and alleviate poverty through (self) employment. Wider implications of the innovations for repositioning mathematical sciences education globally are explored in this article.

Statistical power analysis in wildlife research

USGS Publications Warehouse

Steidl, R.J.; Hayes, J.P.

1997-01-01

Statistical power analysis can be used to increase the efficiency of research efforts and to clarify research results. Power analysis is most valuable in the design or planning phases of research efforts. Such prospective (a priori) power analyses can be used to guide research design and to estimate the number of samples necessary to achieve a high probability of detecting biologically significant effects. Retrospective (a posteriori) power analysis has been advocated as a method to increase information about hypothesis tests that were not rejected. However, estimating power for tests of null hypotheses that were not rejected with the effect size observed in the study is incorrect; these power estimates will always be a??0.50 when bias adjusted and have no relation to true power. Therefore, retrospective power estimates based on the observed effect size for hypothesis tests that were not rejected are misleading; retrospective power estimates are only meaningful when based on effect sizes other than the observed effect size, such as those effect sizes hypothesized to be biologically significant. Retrospective power analysis can be used effectively to estimate the number of samples or effect size that would have been necessary for a completed study to have rejected a specific null hypothesis. Simply presenting confidence intervals can provide additional information about null hypotheses that were not rejected, including information about the size of the true effect and whether or not there is adequate evidence to 'accept' a null hypothesis as true. We suggest that (1) statistical power analyses be routinely incorporated into research planning efforts to increase their efficiency, (2) confidence intervals be used in lieu of retrospective power analyses for null hypotheses that were not rejected to assess the likely size of the true effect, (3) minimum biologically significant effect sizes be used for all power analyses, and (4) if retrospective power estimates are to

The Effectiveness of Contextual Learning on Physics Achievement in Career Technical Education

NASA Astrophysics Data System (ADS)

Arcand, Scott Andrew

The purpose of this casual-comparative study was to determine if students being taught the Minnesota Science Physics Standards via contextual learning methods in Project Lead the Way (PLTW) Principles of Engineering or the PLTW Aerospace Engineering courses, taught by a Career Technical Education (CTE) teacher, achieve at the same rate as students in a physics course taught by a science teacher. The PLTW courses only cover the standards taught in the first trimester of physics. The PLTW courses are two periods long for one trimester. Students who successfully pass the PLTW Principles of Engineering course or the PLTW Engineering Aerospace course earn one-half credit in physics and one-half elective credit. The instrument used to measure student achievement was the district common summative assessment for physics. The Common Summative Assessment scores were pulled from the data warehouse from the first trimester of the 2013-2014 school year. Implications of the research address concepts of contextual learning especially in the Career Technical Education space. The mean score for Physics students (30.916) and PLTW Principles of Engineering students (32.333) was not statistically significantly different. Students in PLTW Principles of Engineering achieved at the same rate as students in physics. Due to the low rate of students participating in the Common Summative Assessment in PTLW Aerospace (four out of seven students), there is not enough data to determine if there is a significant difference in the Physics A scores and PLTW Aerospace Engineering scores.

Sex Differences in Attribution of Achievement and Actual Achievement.

ERIC Educational Resources Information Center

Erkut, Sumru

One-hundred-seventy-six male and 116 female college freshmen took part in a questionnaire study of sex differences in attribution of achievemnt. Achievement was operationalized as grade point index, a performance measure of significance to the subjects, where success-failure feedback is contingent on one's own performance. The best predictor of…

Using hierarchical linear growth models to evaluate protective mechanisms that mediate science achievement

NASA Astrophysics Data System (ADS)

von Secker, Clare Elaine

The study of students at risk is a major topic of science education policy and discussion. Much research has focused on describing conditions and problems associated with the statistical risk of low science achievement among individuals who are members of groups characterized by problems such as poverty and social disadvantage. But outcomes attributed to these factors do not explain the nature and extent of mechanisms that account for differences in performance among individuals at risk. There is ample theoretical and empirical evidence that demographic differences should be conceptualized as social contexts, or collections of variables, that alter the psychological significance and social demands of life events, and affect subsequent relationships between risk and resilience. The hierarchical linear growth models used in this dissertation provide greater specification of the role of social context and the protective effects of attitude, expectations, parenting practices, peer influences, and learning opportunities on science achievement. While the individual influences of these protective factors on science achievement were small, their cumulative effect was substantial. Meta-analysis conducted on the effects associated with psychological and environmental processes that mediate risk mechanisms in sixteen social contexts revealed twenty-two significant differences between groups of students. Positive attitudes, high expectations, and more intense science course-taking had positive effects on achievement of all students, although these factors were not equally protective in all social contexts. In general, effects associated with authoritative parenting and peer influences were negative, regardless of social context. An evaluation comparing the performance and stability of hierarchical linear growth models with traditional repeated measures models is included as well.

Correlation Between University Students' Kinematic Achievement and Learning Styles

NASA Astrophysics Data System (ADS)

Çirkinoǧlu, A. G.; Dem&ircidot, N.

2007-04-01

In the literature, some researches on kinematics revealed that students have many difficulties in connecting graphs and physics. Also some researches showed that the method used in classroom affects students' further learning. In this study the correlation between university students' kinematics achieve and learning style are investigated. In this purpose Kinematics Achievement Test and Learning Style Inventory were applied to 573 students enrolled in general physics 1 courses at Balikesir University in the fall semester of 2005-2006. Kinematics Test, consists of 12 multiple choose and 6 open ended questions, was developed by researchers to assess students' understanding, interpreting, and drawing graphs. Learning Style Inventory, a 24 items test including visual, auditory, and kinesthetic learning styles, was developed and used by Barsch. The data obtained from in this study were analyzed necessary statistical calculations (T-test, correlation, ANOVA, etc.) by using SPSS statistical program. Based on the research findings, the tentative recommendations are made.

The achievement impact of the inclusion model on the standardized test scores of general education students

NASA Astrophysics Data System (ADS)

Garrett-Rainey, Syrena

The purpose of this study was to compare the achievement of general education students within regular education classes to the achievement of general education students in inclusion/co-teach classes to determine whether there was a significant difference in the achievement between the two groups. The school district's inclusion/co-teach model included ongoing professional development support for teachers and administrators. General education teachers, special education teachers, and teacher assistants collaborated to develop instructional strategies to provide additional remediation to help students to acquire the skills needed to master course content. This quantitative study reviewed the end-of course test (EoCT) scores of Grade 10 physical science and math students within an urban school district. It is not known whether general education students in an inclusive/co-teach science or math course will demonstrate a higher achievement on the EoCT in math or science than students not in an inclusive/co-teach classroom setting. In addition, this study sought to determine if students classified as low socioeconomic status benefited from participating in co-teaching classrooms as evidenced by standardized tests. Inferential statistics were used to determine whether there was a significant difference between the achievements of the treatment group (inclusion/co-teach) and the control group (non-inclusion/co-teach). The findings can be used to provide school districts with optional instructional strategies to implement in the diverse classroom setting in the modern classroom to increase academic performance on state standardized tests.

Statistically accurate low-order models for uncertainty quantification in turbulent dynamical systems.

PubMed

Sapsis, Themistoklis P; Majda, Andrew J

2013-08-20

A framework for low-order predictive statistical modeling and uncertainty quantification in turbulent dynamical systems is developed here. These reduced-order, modified quasilinear Gaussian (ROMQG) algorithms apply to turbulent dynamical systems in which there is significant linear instability or linear nonnormal dynamics in the unperturbed system and energy-conserving nonlinear interactions that transfer energy from the unstable modes to the stable modes where dissipation occurs, resulting in a statistical steady state; such turbulent dynamical systems are ubiquitous in geophysical and engineering turbulence. The ROMQG method involves constructing a low-order, nonlinear, dynamical system for the mean and covariance statistics in the reduced subspace that has the unperturbed statistics as a stable fixed point and optimally incorporates the indirect effect of non-Gaussian third-order statistics for the unperturbed system in a systematic calibration stage. This calibration procedure is achieved through information involving only the mean and covariance statistics for the unperturbed equilibrium. The performance of the ROMQG algorithm is assessed on two stringent test cases: the 40-mode Lorenz 96 model mimicking midlatitude atmospheric turbulence and two-layer baroclinic models for high-latitude ocean turbulence with over 125,000 degrees of freedom. In the Lorenz 96 model, the ROMQG algorithm with just a single mode captures the transient response to random or deterministic forcing. For the baroclinic ocean turbulence models, the inexpensive ROMQG algorithm with 252 modes, less than 0.2% of the total, captures the nonlinear response of the energy, the heat flux, and even the one-dimensional energy and heat flux spectra.

Statistical Transmutation in Floquet Driven Optical Lattices.

PubMed

Sedrakyan, Tigran A; Galitski, Victor M; Kamenev, Alex

2015-11-06

We show that interacting bosons in a periodically driven two dimensional (2D) optical lattice may effectively exhibit fermionic statistics. The phenomenon is similar to the celebrated Tonks-Girardeau regime in 1D. The Floquet band of a driven lattice develops the moat shape, i.e., a minimum along a closed contour in the Brillouin zone. Such degeneracy of the kinetic energy favors fermionic quasiparticles. The statistical transmutation is achieved by the Chern-Simons flux attachment similar to the fractional quantum Hall case. We show that the velocity distribution of the released bosons is a sensitive probe of the fermionic nature of their stationary Floquet state.

Multiple intelligences and alternative teaching strategies: The effects on student academic achievement, conceptual understanding, and attitude

NASA Astrophysics Data System (ADS)

Baragona, Michelle

The purpose of this study was to investigate the interactions between multiple intelligence strengths and alternative teaching methods on student academic achievement, conceptual understanding and attitudes. The design was a quasi-experimental study, in which students enrolled in Principles of Anatomy and Physiology, a developmental biology course, received lecture only, problem-based learning with lecture, or peer teaching with lecture. These students completed the Multiple Intelligence Inventory to determine their intelligence strengths, the Students' Motivation Toward Science Learning questionnaire to determine student attitudes towards learning in science, multiple choice tests to determine academic achievement, and open-ended questions to determine conceptual understanding. Effects of intelligence types and teaching methods on academic achievement and conceptual understanding were determined statistically by repeated measures ANOVAs. No significance occurred in academic achievement scores due to lab group or due to teaching method used; however, significant interactions between group and teaching method did occur in students with strengths in logical-mathematical, interpersonal, kinesthetic, and intrapersonal intelligences. Post-hoc analysis using Tukey HSD tests revealed students with strengths in logical-mathematical intelligence and enrolled in Group Three scored significantly higher when taught by problem-based learning (PBL) as compared to peer teaching (PT). No significance occurred in conceptual understanding scores due to lab group or due to teaching method used; however, significant interactions between group and teaching method did occur in students with strengths in musical, kinesthetic, intrapersonal, and spatial intelligences. Post-hoc analysis using Tukey HSD tests revealed students with strengths in logical-mathematical intelligence and enrolled in Group Three scored significantly higher when taught by lecture as compared to PBL. Students with

Basic Statistical Concepts and Methods for Earth Scientists

USGS Publications Warehouse

Olea, Ricardo A.

2008-01-01

INTRODUCTION Statistics is the science of collecting, analyzing, interpreting, modeling, and displaying masses of numerical data primarily for the characterization and understanding of incompletely known systems. Over the years, these objectives have lead to a fair amount of analytical work to achieve, substantiate, and guide descriptions and inferences.

Can Community and School-Based Supports Improve the Achievement of First-Generation Immigrant Children Attending High-Poverty Schools?

PubMed

Dearing, Eric; Walsh, Mary E; Sibley, Erin; Lee-St John, Terry; Foley, Claire; Raczek, Anastacia E

2016-05-01

Using a quasi-experimental design, the effects of a student support intervention were estimated for the math and reading achievement of first-generation immigrant children (n = 667, M = 11.05 years of age) attending high-poverty, urban elementary schools. The intervention was designed to help schools identify developmental strengths and barriers to learning and, in turn, connect children to community and school supports aligned with their strengths and needs. By exploiting within-school changes in the implementation of the intervention, the present study revealed statistically and practically significant treatment effects indicating improvements in math and reading achievement at the end of elementary school. In addition, the intervention appears to considerably narrow achievement gaps between English language learners and immigrant children proficient in English. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Effect size and statistical power in the rodent fear conditioning literature - A systematic review.

PubMed

Carneiro, Clarissa F D; Moulin, Thiago C; Macleod, Malcolm R; Amaral, Olavo B

2018-01-01

Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science.

Academic Achievement in Physics-Chemistry: The Predictive Effect of Attitudes and Reasoning Abilities

PubMed Central

Vilia, Paulo N.; Candeias, Adelinda A.; Neto, António S.; Franco, Maria Da Glória S.; Melo, Madalena

2017-01-01

Science education plays a critical role as political priority due to its fundamental importance in engaging students to pursue technological careers considered essential in modern societies, in order to face scientific development challenges. High-level achievement on science education and positive attitudes toward science constitutes a crucial challenge for formal education. Several studies indicate close relationships between students’ attitudes, cognitive abilities, and academic achievement. The main purpose of this study is to analyze the impact of student’s attitudes toward the school discipline of Physics and Chemistry and their reasoning abilities on academic achievement on that school subject, among Portuguese 9th grade students using the data collected during the Project Academic Performance and Development: a longitudinal study on the effects of school transitions in Portuguese students (PTDC/CPE-CED/104884/2008). The participants were 470 students (267 girls – 56.8% and 203 boys – 43.2%), aged 14–16 years old (μ = 14.3 ± 0.58). The attitude data were collected using the Attitude toward Physics-Chemistry Questionnaire (ATPCQ) and, the Reasoning Test Battery (RTB) was used to assess the students reasoning abilities. Achievement was measured using the students’ quarterly (9-week) grades in the physics and chemistry subject. The relationships between the attitude dimensions toward Physics-chemistry and the reasoning dimensions and achievement in each of the three school terms were assessed by multiple regression stepwise analyses and standardized regression coefficients (β), calculated with IBM SPSS Statistics 21 software. Both variables studied proved to be significant predictor variables of school achievement. The models obtained from the use of both variables were always stronger accounting for higher proportions of student’s grade variations. The results show that ATPCQ and RTB had a significantly positive relationship with student�

Academic Achievement of Girls in Rural Schools in Kenya

ERIC Educational Resources Information Center

Mungai, A. M.

2012-01-01

This study examined the effect of two family factors (financial, social capital) and school factors on students' achievement. One hundred eighty two, seventh-grade female students from nine schools in Muranga district, Kenya, were studied. The statistical procedures included logit regression, cross-tabulations, frequency counting and chi-square…

Statistical Reporting Errors and Collaboration on Statistical Analyses in Psychological Science.

PubMed

Veldkamp, Coosje L S; Nuijten, Michèle B; Dominguez-Alvarez, Linda; van Assen, Marcel A L M; Wicherts, Jelte M

2014-01-01

Statistical analysis is error prone. A best practice for researchers using statistics would therefore be to share data among co-authors, allowing double-checking of executed tasks just as co-pilots do in aviation. To document the extent to which this 'co-piloting' currently occurs in psychology, we surveyed the authors of 697 articles published in six top psychology journals and asked them whether they had collaborated on four aspects of analyzing data and reporting results, and whether the described data had been shared between the authors. We acquired responses for 49.6% of the articles and found that co-piloting on statistical analysis and reporting results is quite uncommon among psychologists, while data sharing among co-authors seems reasonably but not completely standard. We then used an automated procedure to study the prevalence of statistical reporting errors in the articles in our sample and examined the relationship between reporting errors and co-piloting. Overall, 63% of the articles contained at least one p-value that was inconsistent with the reported test statistic and the accompanying degrees of freedom, and 20% of the articles contained at least one p-value that was inconsistent to such a degree that it may have affected decisions about statistical significance. Overall, the probability that a given p-value was inconsistent was over 10%. Co-piloting was not found to be associated with reporting errors.

Statistical Exposé of a Multiple-Compartment Anaerobic Reactor Treating Domestic Wastewater.

PubMed

Pfluger, Andrew R; Hahn, Martha J; Hering, Amanda S; Munakata-Marr, Junko; Figueroa, Linda

2018-06-01

  Mainstream anaerobic treatment of domestic wastewater is a promising energy-generating treatment strategy; however, such reactors operated in colder regions are not well characterized. Performance data from a pilot-scale, multiple-compartment anaerobic reactor taken over 786 days were subjected to comprehensive statistical analyses. Results suggest that chemical oxygen demand (COD) was a poor proxy for organics in anaerobic systems as oxygen demand from dissolved inorganic material, dissolved methane, and colloidal material influence dissolved and particulate COD measurements. Additionally, univariate and functional boxplots were useful in visualizing variability in contaminant concentrations and identifying statistical outliers. Further, significantly different dissolved organic removal and methane production was observed between operational years, suggesting that anaerobic reactor systems may not achieve steady-state performance within one year. Last, modeling multiple-compartment reactor systems will require data collected over at least two years to capture seasonal variations of the major anaerobic microbial functions occurring within each reactor compartment.

Statistical theory of dynamo

NASA Astrophysics Data System (ADS)

Kim, E.; Newton, A. P.

2012-04-01

One major problem in dynamo theory is the multi-scale nature of the MHD turbulence, which requires statistical theory in terms of probability distribution functions. In this contribution, we present the statistical theory of magnetic fields in a simplified mean field α-Ω dynamo model by varying the statistical property of alpha, including marginal stability and intermittency, and then utilize observational data of solar activity to fine-tune the mean field dynamo model. Specifically, we first present a comprehensive investigation into the effect of the stochastic parameters in a simplified α-Ω dynamo model. Through considering the manifold of marginal stability (the region of parameter space where the mean growth rate is zero), we show that stochastic fluctuations are conductive to dynamo. Furthermore, by considering the cases of fluctuating alpha that are periodic and Gaussian coloured random noise with identical characteristic time-scales and fluctuating amplitudes, we show that the transition to dynamo is significantly facilitated for stochastic alpha with random noise. Furthermore, we show that probability density functions (PDFs) of the growth-rate, magnetic field and magnetic energy can provide a wealth of useful information regarding the dynamo behaviour/intermittency. Finally, the precise statistical property of the dynamo such as temporal correlation and fluctuating amplitude is found to be dependent on the distribution the fluctuations of stochastic parameters. We then use observations of solar activity to constrain parameters relating to the effect in stochastic α-Ω nonlinear dynamo models. This is achieved through performing a comprehensive statistical comparison by computing PDFs of solar activity from observations and from our simulation of mean field dynamo model. The observational data that are used are the time history of solar activity inferred for C14 data in the past 11000 years on a long time scale and direct observations of the sun spot

Spatial Statistics for Tumor Cell Counting and Classification

NASA Astrophysics Data System (ADS)

Wirjadi, Oliver; Kim, Yoo-Jin; Breuel, Thomas

To count and classify cells in histological sections is a standard task in histology. One example is the grading of meningiomas, benign tumors of the meninges, which requires to assess the fraction of proliferating cells in an image. As this process is very time consuming when performed manually, automation is required. To address such problems, we propose a novel application of Markov point process methods in computer vision, leading to algorithms for computing the locations of circular objects in images. In contrast to previous algorithms using such spatial statistics methods in image analysis, the present one is fully trainable. This is achieved by combining point process methods with statistical classifiers. Using simulated data, the method proposed in this paper will be shown to be more accurate and more robust to noise than standard image processing methods. On the publicly available SIMCEP benchmark for cell image analysis algorithms, the cell count performance of the present paper is significantly more accurate than results published elsewhere, especially when cells form dense clusters. Furthermore, the proposed system performs as well as a state-of-the-art algorithm for the computer-aided histological grading of meningiomas when combined with a simple k-nearest neighbor classifier for identifying proliferating cells.

Predicting Acquisition of Learning Outcomes: A Comparison of Traditional and Activity-Based Instruction in an Introductory Statistics Course.

ERIC Educational Resources Information Center

Geske, Jenenne A.; Mickelson, William T.; Bandalos, Deborah L.; Jonson, Jessica; Smith, Russell W.

The bulk of experimental research related to reforms in the teaching of statistics concentrates on the effects of alternative teaching methods on statistics achievement. This study expands on that research by including an examination of the effects of instructor and the interaction between instructor and method on achievement as well as attitudes,…

Statistics 101 for Radiologists.

PubMed

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. © RSNA, 2015.

A meta-analysis of self-reported achievement goals and nonself-report performance across three achievement domains (work, sports, and education).

PubMed

Van Yperen, Nico W; Blaga, Monica; Postmes, Tom

2014-01-01

During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that - overall - approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of performance

A Meta-Analysis of Self-Reported Achievement Goals and Nonself-Report Performance across Three Achievement Domains (Work, Sports, and Education)

PubMed Central

Van Yperen, Nico W.; Blaga, Monica; Postmes, Tom

2014-01-01

During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual’s drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that – overall – approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of

Statistical shear lag model - unraveling the size effect in hierarchical composites.

PubMed

Wei, Xiaoding; Filleter, Tobin; Espinosa, Horacio D

2015-05-01

Numerous experimental and computational studies have established that the hierarchical structures encountered in natural materials, such as the brick-and-mortar structure observed in sea shells, are essential for achieving defect tolerance. Due to this hierarchy, the mechanical properties of natural materials have a different size dependence compared to that of typical engineered materials. This study aimed to explore size effects on the strength of bio-inspired staggered hierarchical composites and to define the influence of the geometry of constituents in their outstanding defect tolerance capability. A statistical shear lag model is derived by extending the classical shear lag model to account for the statistics of the constituents' strength. A general solution emerges from rigorous mathematical derivations, unifying the various empirical formulations for the fundamental link length used in previous statistical models. The model shows that the staggered arrangement of constituents grants composites a unique size effect on mechanical strength in contrast to homogenous continuous materials. The model is applied to hierarchical yarns consisting of double-walled carbon nanotube bundles to assess its predictive capabilities for novel synthetic materials. Interestingly, the model predicts that yarn gauge length does not significantly influence the yarn strength, in close agreement with experimental observations. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Forest statistics of western Kentucky

Treesearch

The Forest Survey Organization Central States Forest Experiment Station

1950-01-01

This Survey Release presents the more significant preliminary statistics on the forest area and timber volume for the western region of Kentucky. Similar reports for the remainder of the state will be published as soon as statistical tabulations are completed. Later, an analytical report for the state will be published which will interpret forest area, timber volume,...

Forest statistics of southern Indiana

Treesearch

The Forest Survey Organization Central States Forest Experiment Station

1951-01-01

This Survey Release presents the more significant preliminary statistics on the forest area and timber volume for each of the three regions of southern Indiana. A similar report will be published for the two northern Indiana regions. Later, an analytical report for the state will be published which will interpret statistics on forest area, timber- volume, growth, and...

Incentivizing with Bonus in a College Statistics Course

ERIC Educational Resources Information Center

Ingalls, Victoria

2018-01-01

Many studies have argued the negative effects of external rewards on internal motivation while others assert that external motivation does not necessarily undermine intrinsic motivation. At a private university, students were given the option to earn bonus points for achieving mastery in the online homework systems associated with Statistics and…

On Statistical Analysis of Neuroimages with Imperfect Registration

PubMed Central

Kim, Won Hwa; Ravi, Sathya N.; Johnson, Sterling C.; Okonkwo, Ozioma C.; Singh, Vikas

2016-01-01

A variety of studies in neuroscience/neuroimaging seek to perform statistical inference on the acquired brain image scans for diagnosis as well as understanding the pathological manifestation of diseases. To do so, an important first step is to register (or co-register) all of the image data into a common coordinate system. This permits meaningful comparison of the intensities at each voxel across groups (e.g., diseased versus healthy) to evaluate the effects of the disease and/or use machine learning algorithms in a subsequent step. But errors in the underlying registration make this problematic, they either decrease the statistical power or make the follow-up inference tasks less effective/accurate. In this paper, we derive a novel algorithm which offers immunity to local errors in the underlying deformation field obtained from registration procedures. By deriving a deformation invariant representation of the image, the downstream analysis can be made more robust as if one had access to a (hypothetical) far superior registration procedure. Our algorithm is based on recent work on scattering transform. Using this as a starting point, we show how results from harmonic analysis (especially, non-Euclidean wavelets) yields strategies for designing deformation and additive noise invariant representations of large 3-D brain image volumes. We present a set of results on synthetic and real brain images where we achieve robust statistical analysis even in the presence of substantial deformation errors; here, standard analysis procedures significantly under-perform and fail to identify the true signal. PMID:27042168

The Relationship of School Absenteeism with Body Mass Index, Academic Achievement, and Socioeconomic Status among Fourth-Grade Children

PubMed Central

Royer, Julie A.; Hardin, James W.; Guinn, Caroline H.; Devlin, Christina M.

2014-01-01

Background Data from a school-based study concerning fourth-grade children’s dietary recall accuracy were linked with data from the South Carolina Department of Education (SCDE) through the South Carolina Budget and Control Board Office of Research and Statistics (ORS) to investigate the relationships of children’s school absenteeism with body mass index (BMI), academic achievement, and socioeconomic status (SES). Methods Data for all variables were available for 920 fourth-grade children during two school years (2005–2006, 2006–2007). Number of school days absent for each child and eligibility for free/reduced-price school meals (SES measure) were provided to ORS by SCDE. Children’s weight and height were measured by research staff; age/sex specific BMI percentile was calculated and grouped into categories. For academic achievement, Palmetto Achievement Challenge Tests scores were provided by the school district. The associations of absenteeism with BMI, academic achievement, SES, and school year were investigated with logistic binomial models using the modified sandwich variance estimator to adjust for multiple outcomes within schools. Results The relationships between absenteeism and each of BMI percentile category and SES were not significant (all coefficient p values > 0.118). The relationship between absenteeism and academic achievement was inversely significant (p value < 0.0001; coefficient = −0.087). Conclusions These results support the inverse relationship between absenteeism and academic achievement that was expected and has been found by other researchers. The lack of significant results concerning the relationships between absenteeism and both BMI and SES disagrees with earlier, limited research. More research to investigate these relationships is needed. PMID:21668882

Perspectives on the Use of Null Hypothesis Statistical Testing. Part III: the Various Nuts and Bolts of Statistical and Hypothesis Testing

ERIC Educational Resources Information Center

Marmolejo-Ramos, Fernando; Cousineau, Denis

2017-01-01

The number of articles showing dissatisfaction with the null hypothesis statistical testing (NHST) framework has been progressively increasing over the years. Alternatives to NHST have been proposed and the Bayesian approach seems to have achieved the highest amount of visibility. In this last part of the special issue, a few alternative…

Teacher learning in technology professional development and its impact on student achievement in science

NASA Astrophysics Data System (ADS)

Lee, Hyunju; Longhurst, Max; Campbell, Todd

2017-07-01

This research investigated teacher learning and teacher beliefs in a two-year technology professional development (TPD) for teachers and its impact on their student achievement in science in the western part of the United States. Middle-school science teachers participated in TPD focused on information communication technologies (ICTs) and their applications in science inquiry pedagogy. Three self-reporting teacher instruments were used alongside their student achievement scores on the end-of-year state-science-test. The teacher self-reporting measures investigated technological literacy, ICT capabilities, and pedagogical beliefs about science inquiry pedagogy. Data were collected every year, and descriptive statistics, t-tests, and Pearson's correlations were used for analysis. We found teachers' technological skills and ICT capabilities increasing over time with significant gains each year. Additionally, teachers' pedagogical beliefs changed to become more science inquiry oriented over time; however, the gains were not significant until after the second year of TPD. Comparisons of teacher learning and belief measures with student achievement revealed that the students' performance was correlated to teachers' pedagogical beliefs about science inquiry, but not to their technological skills nor to their ICT capabilities. This research suggests that pedagogical considerations should be foregrounded in TPD and that this may require more longitudinal TPD to ensure that technology integration in science instruction is consequential to student learning.

The applications of statistical quantification techniques in nanomechanics and nanoelectronics.

PubMed

Mai, Wenjie; Deng, Xinwei

2010-10-08

Although nanoscience and nanotechnology have been developing for approximately two decades and have achieved numerous breakthroughs, the experimental results from nanomaterials with a higher noise level and poorer repeatability than those from bulk materials still remain as a practical issue, and challenge many techniques of quantification of nanomaterials. This work proposes a physical-statistical modeling approach and a global fitting statistical method to use all the available discrete data or quasi-continuous curves to quantify a few targeted physical parameters, which can provide more accurate, efficient and reliable parameter estimates, and give reasonable physical explanations. In the resonance method for measuring the elastic modulus of ZnO nanowires (Zhou et al 2006 Solid State Commun. 139 222-6), our statistical technique gives E = 128.33 GPa instead of the original E = 108 GPa, and unveils a negative bias adjustment f(0). The causes are suggested by the systematic bias in measuring the length of the nanowires. In the electronic measurement of the resistivity of a Mo nanowire (Zach et al 2000 Science 290 2120-3), the proposed new method automatically identified the importance of accounting for the Ohmic contact resistance in the model of the Ohmic behavior in nanoelectronics experiments. The 95% confidence interval of resistivity in the proposed one-step procedure is determined to be 3.57 +/- 0.0274 x 10( - 5) ohm cm, which should be a more reliable and precise estimate. The statistical quantification technique should find wide applications in obtaining better estimations from various systematic errors and biased effects that become more significant at the nanoscale.

BETTER STATISTICS FOR BETTER DECISIONS: REJECTING NULL HYPOTHESES STATISTICAL TESTS IN FAVOR OF REPLICATION STATISTICS

PubMed Central

SANABRIA, FEDERICO; KILLEEN, PETER R.

2008-01-01

Despite being under challenge for the past 50 years, null hypothesis significance testing (NHST) remains dominant in the scientific field for want of viable alternatives. NHST, along with its significance level p, is inadequate for most of the uses to which it is put, a flaw that is of particular interest to educational practitioners who too often must use it to sanctify their research. In this article, we review the failure of NHST and propose prep, the probability of replicating an effect, as a more useful statistic for evaluating research and aiding practical decision making. PMID:19122766

Achievable Strength-Based Signal Detection in Quantity-Constrained PAM OOK Concentration-Encoded Molecular Communication.

PubMed

Mahfuz, Mohammad Upal

2016-10-01

In this paper, the expressions of achievable strength-based detection probabilities of concentration-encoded molecular communication (CEMC) system have been derived based on finite pulsewidth (FP) pulse-amplitude modulated (PAM) on-off keying (OOK) modulation scheme and strength threshold. An FP-PAM system is characterized by its duty cycle α that indicates the fraction of the entire symbol duration the transmitter remains on and transmits the signal. Results show that the detection performance of an FP-PAM OOK CEMC system significantly depends on the statistical distribution parameters of diffusion-based propagation noise and intersymbol interference (ISI). Analytical detection performance of an FP-PAM OOK CEMC system under ISI scenario has been explained and compared based on receiver operating characteristics (ROC) for impulse (i.e., spike)-modulated (IM) and FP-PAM CEMC schemes. It is shown that the effects of diffusion noise and ISI on ROC can be explained separately based on their communication range-dependent statistics. With full duty cycle, an FP-PAM scheme provides significantly worse performance than an IM scheme. The paper also analyzes the performance of the system when duty cycle, transmission data rate, and quantity of molecules vary.

Mathematical background and attitudes toward statistics in a sample of Spanish college students.

PubMed

Carmona, José; Martínez, Rafael J; Sánchez, Manuel

2005-08-01

To examine the relation of mathematical background and initial attitudes toward statistics of Spanish college students in social sciences the Survey of Attitudes Toward Statistics was given to 827 students. Multivariate analyses tested the effects of two indicators of mathematical background (amount of exposure and achievement in previous courses) on the four subscales. Analysis suggested grades in previous courses are more related to initial attitudes toward statistics than the number of mathematics courses taken. Mathematical background was related with students' affective responses to statistics but not with their valuing of statistics. Implications of possible research are discussed.

Family, school, and community factors and relationships to racial-ethnic attitudes and academic achievement.

PubMed

Smith, Emilie Phillips; Atkins, Jacqueline; Connell, Christian M

2003-09-01

This study examined family, school, and community factors and the relationships to racial-ethnic attitudes and academic achievement among 98 African American fourth-grade children. It has been posited that young people who feel better about their racial-ethnic background have better behavioral and academic outcomes, yet there is a need for more empirical tests of this premise. Psychometric information is reported on measures of parent, teacher, and child racial-ethnic attitudes. Path analysis was used to investigate ecological variables potentially related to children's racial-ethnic attitudes and achievement. Parental education and level of racial-ethnic pride were correlated and both were related to children's achievement though in the final path model, only the path from parental education level was statistically significant. Children whose teachers exhibited higher levels of racial-ethnic trust and perceived fewer barriers due to race and ethnicity evidenced more trust and optimism as well. Children living in communities with higher proportions of college-educated residents also exhibited more positive racial-ethnic attitudes. For children, higher racial-ethnic pride was related to higher achievement measured by grades and standardized test scores, while racial distrust and perception of barriers due to race were related to reduced performance. This study suggests that family, school, and community are all important factors related to children's racial-ethnic attitudes and also to their academic achievement.

The Effect of Problem-Solving Instruction on the Programming Self-efficacy and Achievement of Introductory Computer Science Students

NASA Astrophysics Data System (ADS)

Maddrey, Elizabeth

Research in academia and industry continues to identify a decline in enrollment in computer science. One major component of this decline in enrollment is a shortage of female students. The primary reasons for the gender gap presented in the research include lack of computer experience prior to their first year in college, misconceptions about the field, negative cultural stereotypes, lack of female mentors and role models, subtle discriminations in the classroom, and lack of self-confidence (Pollock, McCoy, Carberry, Hundigopal, & You, 2004). Male students are also leaving the field due to misconceptions about the field, negative cultural stereotypes, and a lack of self-confidence. Analysis of first year attrition revealed that one of the major challenges faced by students of both genders is a lack of problem-solving skills (Beaubouef, Lucas & Howatt, 2001; Olsen, 2005; Paxton & Mumey, 2001). The purpose of this study was to investigate whether specific, non-mathematical problem-solving instruction as part of introductory programming courses significantly increased computer programming self-efficacy and achievement of students. The results of this study showed that students in the experimental group had significantly higher achievement than students in the control group. While this shows statistical significance, due to the effect size and disordinal nature of the data between groups, care has to be taken in its interpretation. The study did not show significantly higher programming self-efficacy among the experimental students. There was not enough data collected to statistically analyze the effect of the treatment on self-efficacy and achievement by gender. However, differences in means were observed between the gender groups, with females in the experimental group demonstrating a higher than average degree of self-efficacy when compared with males in the experimental group and both genders in the control group. These results suggest that the treatment from this

Differential Effects of Goal Setting and Value Reappraisal on College Women's Motivation and Achievement in Statistics

ERIC Educational Resources Information Center

Acee, Taylor Wayne

2009-01-01

The purpose of this dissertation was to investigate the differential effects of goal setting and value reappraisal on female students' self-efficacy beliefs, value perceptions, exam performance and continued interest in statistics. It was hypothesized that the Enhanced Goal Setting Intervention (GS-E) would positively impact students'…

Lessons from Inferentialism for Statistics Education

ERIC Educational Resources Information Center

Bakker, Arthur; Derry, Jan

2011-01-01

This theoretical paper relates recent interest in informal statistical inference (ISI) to the semantic theory termed inferentialism, a significant development in contemporary philosophy, which places inference at the heart of human knowing. This theory assists epistemological reflection on challenges in statistics education encountered when…

Achievement Goal Orientations and Adolescents’ Subjective Well-Being in School: The Mediating Roles of Academic Social Comparison Directions

PubMed Central

Tian, Lili; Yu, Tingting; Huebner, E. Scott

2017-01-01

The purpose of this study was to examine the multiple mediational roles of academic social comparison directions (upward academic social comparison and downward academic social comparison) on the relationships between achievement goal orientations (i.e., mastery goals, performance-approach goals, and performance-avoidance goals) and subjective well-being (SWB) in school (school satisfaction, school affect) in adolescent students in China. A total of 883 Chinese adolescent students (430 males; Mean age = 12.99) completed a multi-measure questionnaire. Structural equation modeling was used to examine the hypotheses. Results indicated that (1) mastery goal orientations and performance-approach goal orientations both showed a statistically significant, positive correlation with SWB in school whereas performance-avoidance goal orientations showed a statistically significant, negative correlation with SWB in school among adolescents; (2) upward academic social comparisons mediated the relation between the three types of achievement goal orientations (i.e., mastery goals, performance-approach goals, and performance-avoidance goals) and SWB in school; (3) downward academic social comparisons mediated the relation between mastery goal orientations and SWB in school as well as the relation between performance-avoidance goal orientations and SWB in school. The findings suggest possible important cultural differences in the antecedents of SWB in school in adolescent students in China compared to adolescent students in Western nations. PMID:28197109

Statistical Reporting Errors and Collaboration on Statistical Analyses in Psychological Science

PubMed Central

Veldkamp, Coosje L. S.; Nuijten, Michèle B.; Dominguez-Alvarez, Linda; van Assen, Marcel A. L. M.; Wicherts, Jelte M.

2014-01-01

Statistical analysis is error prone. A best practice for researchers using statistics would therefore be to share data among co-authors, allowing double-checking of executed tasks just as co-pilots do in aviation. To document the extent to which this ‘co-piloting’ currently occurs in psychology, we surveyed the authors of 697 articles published in six top psychology journals and asked them whether they had collaborated on four aspects of analyzing data and reporting results, and whether the described data had been shared between the authors. We acquired responses for 49.6% of the articles and found that co-piloting on statistical analysis and reporting results is quite uncommon among psychologists, while data sharing among co-authors seems reasonably but not completely standard. We then used an automated procedure to study the prevalence of statistical reporting errors in the articles in our sample and examined the relationship between reporting errors and co-piloting. Overall, 63% of the articles contained at least one p-value that was inconsistent with the reported test statistic and the accompanying degrees of freedom, and 20% of the articles contained at least one p-value that was inconsistent to such a degree that it may have affected decisions about statistical significance. Overall, the probability that a given p-value was inconsistent was over 10%. Co-piloting was not found to be associated with reporting errors. PMID:25493918

Initial phantom study comparing image quality in computed tomography using adaptive statistical iterative reconstruction and new adaptive statistical iterative reconstruction v.

PubMed

Lim, Kyungjae; Kwon, Heejin; Cho, Jinhan; Oh, Jongyoung; Yoon, Seongkuk; Kang, Myungjin; Ha, Dongho; Lee, Jinhwa; Kang, Eunju

2015-01-01

The purpose of this study was to assess the image quality of a novel advanced iterative reconstruction (IR) method called as "adaptive statistical IR V" (ASIR-V) by comparing the image noise, contrast-to-noise ratio (CNR), and spatial resolution from those of filtered back projection (FBP) and adaptive statistical IR (ASIR) on computed tomography (CT) phantom image. We performed CT scans at 5 different tube currents (50, 70, 100, 150, and 200 mA) using 3 types of CT phantoms. Scanned images were subsequently reconstructed in 7 different scan settings, such as FBP, and 3 levels of ASIR and ASIR-V (30%, 50%, and 70%). The image noise was measured in the first study using body phantom. The CNR was measured in the second study using contrast phantom and the spatial resolutions were measured in the third study using a high-resolution phantom. We compared the image noise, CNR, and spatial resolution among the 7 reconstructed image scan settings to determine whether noise reduction, high CNR, and high spatial resolution could be achieved at ASIR-V. At quantitative analysis of the first and second studies, it showed that the images reconstructed using ASIR-V had reduced image noise and improved CNR compared with those of FBP and ASIR (P < 0.001). At qualitative analysis of the third study, it also showed that the images reconstructed using ASIR-V had significantly improved spatial resolution than those of FBP and ASIR (P < 0.001). Our phantom studies showed that ASIR-V provides a significant reduction in image noise and a significant improvement in CNR as well as spatial resolution. Therefore, this technique has the potential to reduce the radiation dose further without compromising image quality.

The application of statistically designed experiments to resistance spot welding

NASA Technical Reports Server (NTRS)

Hafley, Robert A.; Hales, Stephen J.

1991-01-01

State-of-the-art Resistance Spot Welding (RSW) equipment has the potential to permit realtime monitoring of operations through advances in computerized process control. In order to realize adaptive feedback capabilities, it is necessary to establish correlations among process variables, welder outputs, and weldment properties. The initial step toward achieving this goal must involve assessment of the effect of specific process inputs and the interactions among these variables on spot weld characteristics. This investigation evaluated these effects through the application of a statistically designed experiment to the RSW process. A half-factorial, Taguchi L sub 16 design was used to understand and refine a RSW schedule developed for welding dissimilar aluminum-lithium alloys of different thickness. The baseline schedule had been established previously by traditional trial and error methods based on engineering judgment and one-factor-at-a-time studies. A hierarchy of inputs with respect to each other was established, and the significance of these inputs with respect to experimental noise was determined. Useful insight was gained into the effect of interactions among process variables, particularly with respect to weldment defects. The effects of equipment related changes associated with disassembly and recalibration were also identified. In spite of an apparent decrease in equipment performance, a significant improvement in the maximum strength for defect-free welds compared to the baseline schedule was achieved.

MIDAS: Regionally linear multivariate discriminative statistical mapping.

PubMed

Varol, Erdem; Sotiras, Aristeidis; Davatzikos, Christos

2018-07-01

statistical significance of the derived statistic by analytically approximating its null distribution without the need for computationally expensive permutation tests. The proposed framework was extensively validated using simulated atrophy in structural magnetic resonance imaging (MRI) and further tested using data from a task-based functional MRI study as well as a structural MRI study of cognitive performance. The performance of the proposed framework was evaluated against standard voxel-wise general linear models and other information mapping methods. The experimental results showed that MIDAS achieves relatively higher sensitivity and specificity in detecting group differences. Together, our results demonstrate the potential of the proposed approach to efficiently map effects of interest in both structural and functional data. Copyright © 2018. Published by Elsevier Inc.

Pisces did not have increased heart failure: data-driven comparisons of binary proportions between levels of a categorical variable can result in incorrect statistical significance levels.

PubMed

Austin, Peter C; Goldwasser, Meredith A

2008-03-01

We examined the impact on statistical inference when a chi(2) test is used to compare the proportion of successes in the level of a categorical variable that has the highest observed proportion of successes with the proportion of successes in all other levels of the categorical variable combined. Monte Carlo simulations and a case study examining the association between astrological sign and hospitalization for heart failure. A standard chi(2) test results in an inflation of the type I error rate, with the type I error rate increasing as the number of levels of the categorical variable increases. Using a standard chi(2) test, the hospitalization rate for Pisces was statistically significantly different from that of the other 11 astrological signs combined (P=0.026). After accounting for the fact that the selection of Pisces was based on it having the highest observed proportion of heart failure hospitalizations, subjects born under the sign of Pisces no longer had a significantly higher rate of heart failure hospitalization compared to the other residents of Ontario (P=0.152). Post hoc comparisons of the proportions of successes across different levels of a categorical variable can result in incorrect inferences.

White Working Class Achievement: An Ethnographic Study of Barriers to Learning in Schools

ERIC Educational Resources Information Center

Demie, Feyisa; Lewis, Kirstin

2011-01-01

This study aims to examine the key barriers to learning to raise achievement of White British pupils with low-income backgrounds. The main findings suggest that the worryingly low-achievement levels of many White working class pupils have been masked by the middle class success in the English school system and government statistics that fail to…

Professional training in the workplace: the role of achievement motivation and locus of control.

PubMed

Suárez-Álvarez, Javier; Campillo-Álvarez, Angela; Fonseca-Pedrero, Eduardo; García-Cueto, Eduardo; Muñiz, José

2013-01-01

The core objective of the present work is to explore the reasons why workers from different employment sectors join training courses to improve their job. To this end we assessed achievement motivation, locus of control and professional qualifications according to the participants' employment sector. The final sample consisted of 1460 active Spanish workers from four different employment sectors: services, catering, metal construction, and others. Of the sample, 40.1% were male and 59.9% female, with a mean age of 33.3 years (SD = 9.7). The results show that the new scale developed to assess achievement motivation, locus of control and workers' qualifications presents adequate psychometric characteristics. Statistically significant differences were found in relation to employment sector. The areas studied showed satisfactory levels of workers' effort and achievement motivation to perform their jobs, though their attitudes toward the training courses as a basis for improving their employability are varied. Workers in the catering sector had higher levels of external attribution and the lowest interest in training. Those in the service sector had higher levels of achievement motivation and effort at work. Future research should develop a joint program covering the public and private sectors for the modification of these beliefs, attitudes and attributions.

Writing for understanding: The effect of using informational writing on student science achievement

NASA Astrophysics Data System (ADS)

Parson, Atiya

The purpose of this quantitative study was to investigate whether or not informational writing in the science curriculum would impact fifth grade students' science achievement and conceptual understanding. The population of this study came from a metropolitan school district in the state of Georgia for school year 2012-2013. The quantitative data included students' pretest, posttest, and writing assessment scores. Examination approaches for this study included (a) examining theories and research on learning views for children, (b) determining how writing across the curriculum has worked, and (c) developing a research design for the present study that was based on findings from previous studies. The study was designed to find (a) whether there is a significant differences in science achievement between fifth-grade students who use informational writing weekly during science instruction and ones that do not, and (b) whether there is a significant differences in conceptual understanding of fifth-grade science content for students who use informational writing weekly and fifth-grade students who do not. To answer these questions, students pretest and posttest results were compared to determine if a statistical significance existed after informational writing was implemented in the experimental group for 10 weeks. The results indicate that there was no significant difference in test scores between students receiving the informational writing intervention and students without this intervention. However, this study found that students receiving informational writing intervention had better performance scores on conceptual writing assessment than the students without the intervention.

The Statistical Power of Planned Comparisons.

ERIC Educational Resources Information Center

Benton, Roberta L.

Basic principles underlying statistical power are examined; and issues pertaining to effect size, sample size, error variance, and significance level are highlighted via the use of specific hypothetical examples. Analysis of variance (ANOVA) and related methods remain popular, although other procedures sometimes have more statistical power against…

Improving comparability of international migration statistics: contributions by the Conference of European Statisticians from 1971 to date.

PubMed

Kelly, J J

1987-01-01

This article summarizes the 3 main types of interrelated activities which the Conference of European Statisticians has worked on to improve the measurement and international comparability of international migration flows. The work has encompassed collaborating with the UN Statistical Commission on the preparation and implementation of the revised international recommendations on statistics of international migration, organizing a regular exchange of data on immigration and emigration flows among the UN Economic Commission for Europe countries and selected countries in other regions, and conducting bilateral studies on international migration within the framework of the Conference's program of work in this field of statistics. The bulk of the work which has been carried out to date by the conference has been conducted rather anonymously and even unobtrusively by the staff of national statistical offices in Economic Commission for Europe countries; they have achieved a modest but important amount of progress during the past 15 years. There is reason to expect that further progress will be made over the next decade, particularly if national statistical offices in the region continue to undertake bilateral studies and endeavor to improve their migration statistics. However, more substantial progress could be achieved if additional countries and organizations established projects aimed at achieving these ends (author's modified).

Effect size and statistical power in the rodent fear conditioning literature – A systematic review

PubMed Central

Macleod, Malcolm R.

2018-01-01

Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science. PMID:29698451

Understanding Statistics - Cancer Statistics

Cancer.gov

Annual reports of U.S. cancer statistics including new cases, deaths, trends, survival, prevalence, lifetime risk, and progress toward Healthy People targets, plus statistical summaries for a number of common cancer types.

P-Value Club: Teaching Significance Level on the Dance Floor

ERIC Educational Resources Information Center

Gray, Jennifer

2010-01-01

Courses: Beginning research methods and statistics courses, as well as advanced communication courses that require reading research articles and completing research projects involving statistics. Objective: Students will understand the difference between significant and nonsignificant statistical results based on p-value.

Substance Use as a Strong Predictor of Poor Academic Achievement among University Students

PubMed Central

Fekadu, Wubalem; Mekonnen, Tefera Chane; Workie, Shimelash Bitew

2017-01-01

Background Substance use is a growing concern globally and its association with students' academic performance is not well studied. Objective This study was aimed to assess the prevalence of substance use (alcohol, tobacco, and khat) and its association with academic performance among university students. Methods Cross-sectional study was conducted among Wolaita Sodo University students. A total of 747 students were selected by using cluster sampling technique. Data were collected by pretested self-administered questionnaire and examined using descriptive statistics and linear regression with 95% confidence intervals. Variables with p value of less than 0.05 were considered as statistically significant. Result Prevalence of substance use (alcohol, tobacco, and khat) was 28.6%. Substance use (current smoking, chewing khat at least weekly, drinking alcohol on a daily basis, and having intimate friend who uses substance) was significantly and negatively associated with students' academic performance. Conclusion Substance use among Wolaita Sodo University students was as common as other studies in Sub-Saharan countries and negatively associated with students' academic achievement. The common practice of substance use and its association with poor academic performance demand the universities to have a good control of substance and to implement youth friendly activities. PMID:28680879

Improved Statistics for Genome-Wide Interaction Analysis

PubMed Central

Ueki, Masao; Cordell, Heather J.

2012-01-01

Recently, Wu and colleagues [1] proposed two novel statistics for genome-wide interaction analysis using case/control or case-only data. In computer simulations, their proposed case/control statistic outperformed competing approaches, including the fast-epistasis option in PLINK and logistic regression analysis under the correct model; however, reasons for its superior performance were not fully explored. Here we investigate the theoretical properties and performance of Wu et al.'s proposed statistics and explain why, in some circumstances, they outperform competing approaches. Unfortunately, we find minor errors in the formulae for their statistics, resulting in tests that have higher than nominal type 1 error. We also find minor errors in PLINK's fast-epistasis and case-only statistics, although theory and simulations suggest that these errors have only negligible effect on type 1 error. We propose adjusted versions of all four statistics that, both theoretically and in computer simulations, maintain correct type 1 error rates under the null hypothesis. We also investigate statistics based on correlation coefficients that maintain similar control of type 1 error. Although designed to test specifically for interaction, we show that some of these previously-proposed statistics can, in fact, be sensitive to main effects at one or both loci, particularly in the presence of linkage disequilibrium. We propose two new “joint effects” statistics that, provided the disease is rare, are sensitive only to genuine interaction effects. In computer simulations we find, in most situations considered, that highest power is achieved by analysis under the correct genetic model. Such an analysis is unachievable in practice, as we do not know this model. However, generally high power over a wide range of scenarios is exhibited by our joint effects and adjusted Wu statistics. We recommend use of these alternative or adjusted statistics and urge caution when using Wu et al

Receptor arrays optimized for natural odor statistics.

PubMed

Zwicker, David; Murugan, Arvind; Brenner, Michael P

2016-05-17

Natural odors typically consist of many molecules at different concentrations. It is unclear how the numerous odorant molecules and their possible mixtures are discriminated by relatively few olfactory receptors. Using an information theoretic model, we show that a receptor array is optimal for this task if it achieves two possibly conflicting goals: (i) Each receptor should respond to half of all odors and (ii) the response of different receptors should be uncorrelated when averaged over odors presented with natural statistics. We use these design principles to predict statistics of the affinities between receptors and odorant molecules for a broad class of odor statistics. We also show that optimal receptor arrays can be tuned to either resolve concentrations well or distinguish mixtures reliably. Finally, we use our results to predict properties of experimentally measured receptor arrays. Our work can thus be used to better understand natural olfaction, and it also suggests ways to improve artificial sensor arrays.

Selection of the Maximum Spatial Cluster Size of the Spatial Scan Statistic by Using the Maximum Clustering Set-Proportion Statistic.

PubMed

Ma, Yue; Yin, Fei; Zhang, Tao; Zhou, Xiaohua Andrew; Li, Xiaosong

2016-01-01

Spatial scan statistics are widely used in various fields. The performance of these statistics is influenced by parameters, such as maximum spatial cluster size, and can be improved by parameter selection using performance measures. Current performance measures are based on the presence of clusters and are thus inapplicable to data sets without known clusters. In this work, we propose a novel overall performance measure called maximum clustering set-proportion (MCS-P), which is based on the likelihood of the union of detected clusters and the applied dataset. MCS-P was compared with existing performance measures in a simulation study to select the maximum spatial cluster size. Results of other performance measures, such as sensitivity and misclassification, suggest that the spatial scan statistic achieves accurate results in most scenarios with the maximum spatial cluster sizes selected using MCS-P. Given that previously known clusters are not required in the proposed strategy, selection of the optimal maximum cluster size with MCS-P can improve the performance of the scan statistic in applications without identified clusters.

Selection of the Maximum Spatial Cluster Size of the Spatial Scan Statistic by Using the Maximum Clustering Set-Proportion Statistic

PubMed Central

Ma, Yue; Yin, Fei; Zhang, Tao; Zhou, Xiaohua Andrew; Li, Xiaosong

2016-01-01

Spatial scan statistics are widely used in various fields. The performance of these statistics is influenced by parameters, such as maximum spatial cluster size, and can be improved by parameter selection using performance measures. Current performance measures are based on the presence of clusters and are thus inapplicable to data sets without known clusters. In this work, we propose a novel overall performance measure called maximum clustering set–proportion (MCS-P), which is based on the likelihood of the union of detected clusters and the applied dataset. MCS-P was compared with existing performance measures in a simulation study to select the maximum spatial cluster size. Results of other performance measures, such as sensitivity and misclassification, suggest that the spatial scan statistic achieves accurate results in most scenarios with the maximum spatial cluster sizes selected using MCS-P. Given that previously known clusters are not required in the proposed strategy, selection of the optimal maximum cluster size with MCS-P can improve the performance of the scan statistic in applications without identified clusters. PMID:26820646

Confounding and Statistical Significance of Indirect Effects: Childhood Adversity, Education, Smoking, and Anxious and Depressive Symptomatology.

PubMed

Sheikh, Mashhood Ahmed

2017-01-01

association between childhood adversity and ADS in adulthood. However, when education was excluded as a mediator-response confounding variable, the indirect effect of childhood adversity on ADS in adulthood was statistically significant ( p < 0.05). This study shows that a careful inclusion of potential confounding variables is important when assessing mediation.

Confounding and Statistical Significance of Indirect Effects: Childhood Adversity, Education, Smoking, and Anxious and Depressive Symptomatology

PubMed Central

Sheikh, Mashhood Ahmed

2017-01-01

association between childhood adversity and ADS in adulthood. However, when education was excluded as a mediator-response confounding variable, the indirect effect of childhood adversity on ADS in adulthood was statistically significant (p < 0.05). This study shows that a careful inclusion of potential confounding variables is important when assessing mediation. PMID:28824498

Mathematics Anxiety and Statistics Anxiety. Shared but Also Unshared Components and Antagonistic Contributions to Performance in Statistics

PubMed Central

Paechter, Manuela; Macher, Daniel; Martskvishvili, Khatuna; Wimmer, Sigrid; Papousek, Ilona

2017-01-01

In many social science majors, e.g., psychology, students report high levels of statistics anxiety. However, these majors are often chosen by students who are less prone to mathematics and who might have experienced difficulties and unpleasant feelings in their mathematics courses at school. The present study investigates whether statistics anxiety is a genuine form of anxiety that impairs students' achievements or whether learners mainly transfer previous experiences in mathematics and their anxiety in mathematics to statistics. The relationship between mathematics anxiety and statistics anxiety, their relationship to learning behaviors and to performance in a statistics examination were investigated in a sample of 225 undergraduate psychology students (164 women, 61 men). Data were recorded at three points in time: At the beginning of term students' mathematics anxiety, general proneness to anxiety, school grades, and demographic data were assessed; 2 weeks before the end of term, they completed questionnaires on statistics anxiety and their learning behaviors. At the end of term, examination scores were recorded. Mathematics anxiety and statistics anxiety correlated highly but the comparison of different structural equation models showed that they had genuine and even antagonistic contributions to learning behaviors and performance in the examination. Surprisingly, mathematics anxiety was positively related to performance. It might be that students realized over the course of their first term that knowledge and skills in higher secondary education mathematics are not sufficient to be successful in statistics. Part of mathematics anxiety may then have strengthened positive extrinsic effort motivation by the intention to avoid failure and may have led to higher effort for the exam preparation. However, via statistics anxiety mathematics anxiety also had a negative contribution to performance. Statistics anxiety led to higher procrastination in the structural

Mathematics Anxiety and Statistics Anxiety. Shared but Also Unshared Components and Antagonistic Contributions to Performance in Statistics.

PubMed

Paechter, Manuela; Macher, Daniel; Martskvishvili, Khatuna; Wimmer, Sigrid; Papousek, Ilona

2017-01-01

In many social science majors, e.g., psychology, students report high levels of statistics anxiety. However, these majors are often chosen by students who are less prone to mathematics and who might have experienced difficulties and unpleasant feelings in their mathematics courses at school. The present study investigates whether statistics anxiety is a genuine form of anxiety that impairs students' achievements or whether learners mainly transfer previous experiences in mathematics and their anxiety in mathematics to statistics. The relationship between mathematics anxiety and statistics anxiety, their relationship to learning behaviors and to performance in a statistics examination were investigated in a sample of 225 undergraduate psychology students (164 women, 61 men). Data were recorded at three points in time: At the beginning of term students' mathematics anxiety, general proneness to anxiety, school grades, and demographic data were assessed; 2 weeks before the end of term, they completed questionnaires on statistics anxiety and their learning behaviors. At the end of term, examination scores were recorded. Mathematics anxiety and statistics anxiety correlated highly but the comparison of different structural equation models showed that they had genuine and even antagonistic contributions to learning behaviors and performance in the examination. Surprisingly, mathematics anxiety was positively related to performance. It might be that students realized over the course of their first term that knowledge and skills in higher secondary education mathematics are not sufficient to be successful in statistics. Part of mathematics anxiety may then have strengthened positive extrinsic effort motivation by the intention to avoid failure and may have led to higher effort for the exam preparation. However, via statistics anxiety mathematics anxiety also had a negative contribution to performance. Statistics anxiety led to higher procrastination in the structural

DYNAMIC STABILITY OF THE SOLAR SYSTEM: STATISTICALLY INCONCLUSIVE RESULTS FROM ENSEMBLE INTEGRATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeebe, Richard E., E-mail: zeebe@soest.hawaii.edu

Due to the chaotic nature of the solar system, the question of its long-term stability can only be answered in a statistical sense, for instance, based on numerical ensemble integrations of nearby orbits. Destabilization of the inner planets, leading to close encounters and/or collisions can be initiated through a large increase in Mercury's eccentricity, with a currently assumed likelihood of ∼1%. However, little is known at present about the robustness of this number. Here I report ensemble integrations of the full equations of motion of the eight planets and Pluto over 5 Gyr, including contributions from general relativity. The resultsmore » show that different numerical algorithms lead to statistically different results for the evolution of Mercury's eccentricity (e{sub M}). For instance, starting at present initial conditions (e{sub M}≃0.21), Mercury's maximum eccentricity achieved over 5 Gyr is, on average, significantly higher in symplectic ensemble integrations using heliocentric rather than Jacobi coordinates and stricter error control. In contrast, starting at a possible future configuration (e{sub M}≃0.53), Mercury's maximum eccentricity achieved over the subsequent 500 Myr is, on average, significantly lower using heliocentric rather than Jacobi coordinates. For example, the probability for e{sub M} to increase beyond 0.53 over 500 Myr is >90% (Jacobi) versus only 40%-55% (heliocentric). This poses a dilemma because the physical evolution of the real system—and its probabilistic behavior—cannot depend on the coordinate system or the numerical algorithm chosen to describe it. Some tests of the numerical algorithms suggest that symplectic integrators using heliocentric coordinates underestimate the odds for destabilization of Mercury's orbit at high initial e{sub M}.« less

Instructional Leadership: A Pathway to Teacher Collaboration and Student Achievement

ERIC Educational Resources Information Center

Miller, Robert J.; Goddard, Yvonne L.; Goddard, Roger; Larsen, Ross; Jacob, Robin

2010-01-01

The purpose of this paper was to test the relationship between principals' instructional leadership and teacher collaboration around instruction to determine whether these measures were statistically related and whether, together, they were associated with academic achievement in elementary schools. Data were obtained from 1605 teachers in 96…

[Big data in official statistics].

PubMed

Zwick, Markus

2015-08-01

The concept of "big data" stands to change the face of official statistics over the coming years, having an impact on almost all aspects of data production. The tasks of future statisticians will not necessarily be to produce new data, but rather to identify and make use of existing data to adequately describe social and economic phenomena. Until big data can be used correctly in official statistics, a lot of questions need to be answered and problems solved: the quality of data, data protection, privacy, and the sustainable availability are some of the more pressing issues to be addressed. The essential skills of official statisticians will undoubtedly change, and this implies a number of challenges to be faced by statistical education systems, in universities, and inside the statistical offices. The national statistical offices of the European Union have concluded a concrete strategy for exploring the possibilities of big data for official statistics, by means of the Big Data Roadmap and Action Plan 1.0. This is an important first step and will have a significant influence on implementing the concept of big data inside the statistical offices of Germany.

Simple Statistics: - Summarized!

ERIC Educational Resources Information Center

Blai, Boris, Jr.

Statistics are an essential tool for making proper judgement decisions. It is concerned with probability distribution models, testing of hypotheses, significance tests and other means of determining the correctness of deductions and the most likely outcome of decisions. Measures of central tendency include the mean, median and mode. A second…

The Importance of Medical Students' Attitudes Regarding Cognitive Competence for Teaching Applied Statistics: Multi-Site Study and Meta-Analysis

PubMed Central

Milic, Natasa M.; Masic, Srdjan; Milin-Lazovic, Jelena; Trajkovic, Goran; Bukumiric, Zoran; Savic, Marko; Milic, Nikola V.; Cirkovic, Andja; Gajic, Milan; Kostic, Mirjana; Ilic, Aleksandra; Stanisavljevic, Dejana

2016-01-01

Background The scientific community increasingly is recognizing the need to bolster standards of data analysis given the widespread concern that basic mistakes in data analysis are contributing to the irreproducibility of many published research findings. The aim of this study was to investigate students’ attitudes towards statistics within a multi-site medical educational context, monitor their changes and impact on student achievement. In addition, we performed a systematic review to better support our future pedagogical decisions in teaching applied statistics to medical students. Methods A validated Serbian Survey of Attitudes Towards Statistics (SATS-36) questionnaire was administered to medical students attending obligatory introductory courses in biostatistics from three medical universities in the Western Balkans. A systematic review of peer-reviewed publications was performed through searches of Scopus, Web of Science, Science Direct, Medline, and APA databases through 1994. A meta-analysis was performed for the correlation coefficients between SATS component scores and statistics achievement. Pooled estimates were calculated using random effects models. Results SATS-36 was completed by 461 medical students. Most of the students held positive attitudes towards statistics. Ability in mathematics and grade point average were associated in a multivariate regression model with the Cognitive Competence score, after adjusting for age, gender and computer ability. The results of 90 paired data showed that Affect, Cognitive Competence, and Effort scores demonstrated significant positive changes. The Cognitive Competence score showed the largest increase (M = 0.48, SD = 0.95). The positive correlation found between the Cognitive Competence score and students’ achievement (r = 0.41; p<0.001), was also shown in the meta-analysis (r = 0.37; 95% CI 0.32–0.41). Conclusion Students' subjective attitudes regarding Cognitive Competence at the beginning of the

The Importance of Medical Students' Attitudes Regarding Cognitive Competence for Teaching Applied Statistics: Multi-Site Study and Meta-Analysis.

PubMed

Milic, Natasa M; Masic, Srdjan; Milin-Lazovic, Jelena; Trajkovic, Goran; Bukumiric, Zoran; Savic, Marko; Milic, Nikola V; Cirkovic, Andja; Gajic, Milan; Kostic, Mirjana; Ilic, Aleksandra; Stanisavljevic, Dejana

2016-01-01

The scientific community increasingly is recognizing the need to bolster standards of data analysis given the widespread concern that basic mistakes in data analysis are contributing to the irreproducibility of many published research findings. The aim of this study was to investigate students' attitudes towards statistics within a multi-site medical educational context, monitor their changes and impact on student achievement. In addition, we performed a systematic review to better support our future pedagogical decisions in teaching applied statistics to medical students. A validated Serbian Survey of Attitudes Towards Statistics (SATS-36) questionnaire was administered to medical students attending obligatory introductory courses in biostatistics from three medical universities in the Western Balkans. A systematic review of peer-reviewed publications was performed through searches of Scopus, Web of Science, Science Direct, Medline, and APA databases through 1994. A meta-analysis was performed for the correlation coefficients between SATS component scores and statistics achievement. Pooled estimates were calculated using random effects models. SATS-36 was completed by 461 medical students. Most of the students held positive attitudes towards statistics. Ability in mathematics and grade point average were associated in a multivariate regression model with the Cognitive Competence score, after adjusting for age, gender and computer ability. The results of 90 paired data showed that Affect, Cognitive Competence, and Effort scores demonstrated significant positive changes. The Cognitive Competence score showed the largest increase (M = 0.48, SD = 0.95). The positive correlation found between the Cognitive Competence score and students' achievement (r = 0.41; p<0.001), was also shown in the meta-analysis (r = 0.37; 95% CI 0.32-0.41). Students' subjective attitudes regarding Cognitive Competence at the beginning of the biostatistics course, which were directly linked to

Transmit Designs for the MIMO Broadcast Channel With Statistical CSI

NASA Astrophysics Data System (ADS)

Wu, Yongpeng; Jin, Shi; Gao, Xiqi; McKay, Matthew R.; Xiao, Chengshan

2014-09-01

We investigate the multiple-input multiple-output broadcast channel with statistical channel state information available at the transmitter. The so-called linear assignment operation is employed, and necessary conditions are derived for the optimal transmit design under general fading conditions. Based on this, we introduce an iterative algorithm to maximize the linear assignment weighted sum-rate by applying a gradient descent method. To reduce complexity, we derive an upper bound of the linear assignment achievable rate of each receiver, from which a simplified closed-form expression for a near-optimal linear assignment matrix is derived. This reveals an interesting construction analogous to that of dirty-paper coding. In light of this, a low complexity transmission scheme is provided. Numerical examples illustrate the significant performance of the proposed low complexity scheme.

Societal Statistics by virtue of the Statistical Drake Equation

NASA Astrophysics Data System (ADS)

Maccone, Claudio

2012-09-01

number of Habitable Planets follows the lognormal distribution as well. But the Dole equation is described by the first FOUR factors of the Drake equation. Thus, we may "divide" the 7-factor Drake equation by the 4-factor Dole equation getting the probability distribution of the last-3-factor Drake equation, i.e. the probability distribution of the SOCIETAL TERMS ONLY. These we study in detail in this paper, achieving new statistical results about the SOCIETAL ASPECTS OF SETI.

Relationships Among Teacher Preparedness and Instructional Approaches to Secondary Student Achievement in STEM: A Secondary Analysis of TIMSS Data

NASA Astrophysics Data System (ADS)

Miller-Ricks, Karen A.

Educational reform efforts in Science, Technology, Engineering, Math (STEM) place emphasis on teachers as conduits for student achievement. The purpose of this study was to use TIMSS 2011 data to examine relationships between Science-Technology-Society (STS) instructional practices (student-centered instruction established to promote learning through real-world applications) teacher preparedness, and student achievement and identify variations of achievement between and among eighth-grade science and math classes. The research was framed by both Harper's Anti-Deficit Achievement Theory and Bronfenbrenner's Ecological Systems Theory (BEST). 501 U.S. schools contributed to the TIMSS 2011 data from both the teacher questionnaires and student booklets. Chi-Square, Spearman Correlation, and 2-level hierarchical linear modeling (HLM) were used to analyze data about teachers' preparedness to teach science and math, frequency of using STS instructional practices, and student achievement. The chi-square null hypothesis for math teachers was rejected, providing the assumption that there was an association between the frequency of using STS instruction in math and teacher preparedness. However, the chi-square null hypothesis for science teachers failed to be rejected, providing the assumption that there was no significant association between the frequency of using STS instruction in science and science teacher preparedness. The Spearman Correlation revealed statistically positively significant differences between STS instruction and science achievement, as well as between teacher preparedness and science achievement. The HLM results suggested that 33% of the variance of mathematics achievement was at the individual level and 66% was at the group level. The results for science teachers suggested that 54% of the variance of science achievement was at the individual level and 46% of the variance was at the group level. The data findings support the conclusion that secondary STEM

Walking through the statistical black boxes of plant breeding.

PubMed

Xavier, Alencar; Muir, William M; Craig, Bruce; Rainey, Katy Martin

2016-10-01

The main statistical procedures in plant breeding are based on Gaussian process and can be computed through mixed linear models. Intelligent decision making relies on our ability to extract useful information from data to help us achieve our goals more efficiently. Many plant breeders and geneticists perform statistical analyses without understanding the underlying assumptions of the methods or their strengths and pitfalls. In other words, they treat these statistical methods (software and programs) like black boxes. Black boxes represent complex pieces of machinery with contents that are not fully understood by the user. The user sees the inputs and outputs without knowing how the outputs are generated. By providing a general background on statistical methodologies, this review aims (1) to introduce basic concepts of machine learning and its applications to plant breeding; (2) to link classical selection theory to current statistical approaches; (3) to show how to solve mixed models and extend their application to pedigree-based and genomic-based prediction; and (4) to clarify how the algorithms of genome-wide association studies work, including their assumptions and limitations.

A statistical approach to selecting and confirming validation targets in -omics experiments

PubMed Central

2012-01-01

Background Genomic technologies are, by their very nature, designed for hypothesis generation. In some cases, the hypotheses that are generated require that genome scientists confirm findings about specific genes or proteins. But one major advantage of high-throughput technology is that global genetic, genomic, transcriptomic, and proteomic behaviors can be observed. Manual confirmation of every statistically significant genomic result is prohibitively expensive. This has led researchers in genomics to adopt the strategy of confirming only a handful of the most statistically significant results, a small subset chosen for biological interest, or a small random subset. But there is no standard approach for selecting and quantitatively evaluating validation targets. Results Here we present a new statistical method and approach for statistically validating lists of significant results based on confirming only a small random sample. We apply our statistical method to show that the usual practice of confirming only the most statistically significant results does not statistically validate result lists. We analyze an extensively validated RNA-sequencing experiment to show that confirming a random subset can statistically validate entire lists of significant results. Finally, we analyze multiple publicly available microarray experiments to show that statistically validating random samples can both (i) provide evidence to confirm long gene lists and (ii) save thousands of dollars and hundreds of hours of labor over manual validation of each significant result. Conclusions For high-throughput -omics studies, statistical validation is a cost-effective and statistically valid approach to confirming lists of significant results. PMID:22738145

Predicting Success in Psychological Statistics Courses.

PubMed

Lester, David

2016-06-01

Many students perform poorly in courses on psychological statistics, and it is useful to be able to predict which students will have difficulties. In a study of 93 undergraduates enrolled in Statistical Methods (18 men, 75 women; M age = 22.0 years, SD = 5.1), performance was significantly associated with sex (female students performed better) and proficiency in algebra in a linear regression analysis. Anxiety about statistics was not associated with course performance, indicating that basic mathematical skills are the best correlate for performance in statistics courses and can usefully be used to stream students into classes by ability. © The Author(s) 2016.

Understanding the Change Styles of Teachers to Improve Student Achievement

ERIC Educational Resources Information Center

Bigby, Arlene May Green

2009-01-01

The topic of this dissertation is the understanding of teacher change styles to improve student achievement. Teachers from public schools in a state located in the northern plains were surveyed regarding their Change Styles (preferred approaches to change) and flexibility scores. The results were statistically analyzed to determine if there were…

Exploring the relationship between time management skills and the academic achievement of African engineering students - a case study

NASA Astrophysics Data System (ADS)

Swart, Arthur James; Lombard, Kobus; de Jager, Henk

2010-03-01

Poor academic success by African engineering students is currently experienced in many higher educational institutions, contributing to lower financial subsidies by local governments. One of the contributing factors to this low academic success may be the poor time management skills of these students. This article endeavours to explore this relationship by means of a theoretical literature review and an empirical study. Numerous studies have been conducted in this regard, but with mixed results. The case study of this article involves a design module termed Design Projects III, where the empirical study incorporated an ex post facto study involving a pre-experimental/exploratory design using descriptive statistics. The results of this study were applied to various tests, which indicated no statistically significant relationship between time management skills and the academic achievement of African engineering students.

Methane mitigation shows significant benefits towards achieving the 1.5 degree target.

NASA Astrophysics Data System (ADS)

Collins, W.; Webber, C.; Cox, P. M.; Huntingford, C.; Lowe, J. A.; Sitch, S.

2017-12-01

Most analyses of allowable carbon emissions to achieve the 1.5 degree target implicitly assume that the ratio of CO2 to non-CO2 greenhouse gases remains near constant, and that all radiative forcing factors have similar impacts on land and ocean carbon storage. Here we determine how plausible reductions in methane emissions will make the carbon targets more feasible. We account for the latest estimates of the methane radiative effect as well as the indirect effects of methane on ozone. We particularly address the differing effects of methane and CO2 mitigation on the land carbon storage including via reduced concentrations of surface ozone. The methodology uses an intermediate complexity climate model (IMOGEN) coupled to a land surface model (JULES) which represents the details of the terrestrial carbon cycle. The carbon emissions inputs to IMOGEN are varied to find allowable pathways consistent with the Paris 1.5 K or 2.0 K targets. The IMOGEN physical parameters are altered to represent the climate characteristics of 38 CMIP5 models (such as climate sensitivity) to provide bounds on the range of allowable CO2 emissions. We examine the effects of three different methane mitigation options that are broadly consistent with the ranges in the SSP scenarios: little mitigation, cost-optimal mitigation, and maximal mitigation. The land and ocean carbon storage increases with methane mitigation, allowing more flexibility in CO2 emission reduction. This is mostly since CO2 fertilisation is reduced less with high methane mitigation, with a small contribution from reduced plant damage with lower surface ozone levels.

A Statistics Curriculum for the Undergraduate Chemistry Major

ERIC Educational Resources Information Center

Schlotter, Nicholas E.

2013-01-01

Our ability to statistically analyze data has grown significantly with the maturing of computer hardware and software. However, the evolution of our statistics capabilities has taken place without a corresponding evolution in the curriculum for the undergraduate chemistry major. Most faculty understands the need for a statistical educational…

Storytelling, statistics and hereditary thought: the narrative support of early statistics.

PubMed

López-Beltrán, Carlos

2006-03-01

This paper's main contention is that some basically methodological developments in science which are apparently distant and unrelated can be seen as part of a sequential story. Focusing on general inferential and epistemological matters, the paper links occurrences separated by both in time and space, by formal and representational issues rather than social or disciplinary links. It focuses on a few limited aspects of several cognitive practices in medical and biological contexts separated by geography, disciplines and decades, but connected by long term transdisciplinary representational and inferential structures and constraints. The paper intends to show a given set of knowledge claims based on organizing statistically empirical data can be seen to have been underpinned by a previous, more familiar, and probably more natural, narrative handling of similar evidence. To achieve that this paper moves from medicine in France in the late eighteenth and early nineteenth century to the second half of the nineteenth century in England among gentleman naturalists, following its subject: the shift from narrative depiction of hereditary transmission of physical peculiarities to posterior statistical articulations of the same phenomena. Some early defenders of heredity as an important (if not the most important) causal presence in the understanding of life adopted singular narratives, in the form of case stories from medical and natural history traditions, to flesh out a special kind of causality peculiar to heredity. This work tries to reconstruct historically the rationale that drove the use of such narratives. It then shows that when this rationale was methodologically challenged, its basic narrative and probabilistic underpinings were transferred to the statistical quantificational tools that took their place.

Statistical characterization of the standard map

NASA Astrophysics Data System (ADS)

Ruiz, Guiomar; Tirnakli, Ugur; Borges, Ernesto P.; Tsallis, Constantino

2017-06-01

The standard map, paradigmatic conservative system in the (x, p) phase space, has been recently shown (Tirnakli and Borges (2016 Sci. Rep. 6 23644)) to exhibit interesting statistical behaviors directly related to the value of the standard map external parameter K. A comprehensive statistical numerical description is achieved in the present paper. More precisely, for large values of K (e.g. K  =  10) where the Lyapunov exponents are neatly positive over virtually the entire phase space consistently with Boltzmann-Gibbs (BG) statistics, we verify that the q-generalized indices related to the entropy production q{ent} , the sensitivity to initial conditions q{sen} , the distribution of a time-averaged (over successive iterations) phase-space coordinate q{stat} , and the relaxation to the equilibrium final state q{rel} , collapse onto a fixed point, i.e. q{ent}=q{sen}=q{stat}=q{rel}=1 . In remarkable contrast, for small values of K (e.g. K  =  0.2) where the Lyapunov exponents are virtually zero over the entire phase space, we verify q{ent}=q{sen}=0 , q{stat} ≃ 1.935 , and q{rel} ≃1.4 . The situation corresponding to intermediate values of K, where both stable orbits and a chaotic sea are present, is discussed as well. The present results transparently illustrate when BG behavior and/or q-statistical behavior are observed.

A Tablet-PC Software Application for Statistics Classes

ERIC Educational Resources Information Center

Probst, Alexandre C.

2014-01-01

A significant deficiency in the area of introductory statistics education exists: Student performance on standardized assessments after a full semester statistics course is poor and students report a very low desire to learn statistics. Research on the current generation of students indicates an affinity for technology and for multitasking.…

Achievable flatness in a large microwave power transmitting antenna

NASA Technical Reports Server (NTRS)

Ried, R. C.

1980-01-01

A dual reference SPS system with pseudoisotropic graphite composite as a representative dimensionally stable composite was studied. The loads, accelerations, thermal environments, temperatures and distortions were calculated for a variety of operational SPS conditions along with statistical considerations of material properties, manufacturing tolerances, measurement accuracy and the resulting loss of sight (LOS) and local slope distributions. A LOS error and a subarray rms slope error of two arc minutes can be achieved with a passive system. Results show that existing materials measurement, manufacturing, assembly and alignment techniques can be used to build the microwave power transmission system antenna structure. Manufacturing tolerance can be critical to rms slope error. The slope error budget can be met with a passive system. Structural joints without free play are essential in the assembly of the large truss structure. Variations in material properties, particularly for coefficient of thermal expansion from part to part, is more significant than actual value.

Breaking the Tradition of Summer Vacation to Raise Academic Achievement

ERIC Educational Resources Information Center

Ramos, Barbara Kay

2011-01-01

This study found that students in settings with a year-round calendar statistically outperformed students with traditional calendars in a school-within-a-school setting in mathematics. The study included reading and math achievement of fifth graders in three school-within-a-school year-round elementary schools. Overall, the study made 16…

Children's School Achievement and Parental Work: An Analysis for Sweden

ERIC Educational Resources Information Center

Norberg-Schonfeldt, Magdalena

2008-01-01

Data from Statistics Sweden on 70 000 students entering upper secondary school in 1994 are used along with socioeconomic characteristics from the 1990 census to explore the relationship between market work by parents in Sweden and their children's educational achievement, measured as the Grade Point Average. The results show that there is a…

Fast, Statistical Model of Surface Roughness for Ion-Solid Interaction Simulations and Efficient Code Coupling

NASA Astrophysics Data System (ADS)

Drobny, Jon; Curreli, Davide; Ruzic, David; Lasa, Ane; Green, David; Canik, John; Younkin, Tim; Blondel, Sophie; Wirth, Brian

2017-10-01

Surface roughness greatly impacts material erosion, and thus plays an important role in Plasma-Surface Interactions. Developing strategies for efficiently introducing rough surfaces into ion-solid interaction codes will be an important step towards whole-device modeling of plasma devices and future fusion reactors such as ITER. Fractal TRIDYN (F-TRIDYN) is an upgraded version of the Monte Carlo, BCA program TRIDYN developed for this purpose that includes an explicit fractal model of surface roughness and extended input and output options for file-based code coupling. Code coupling with both plasma and material codes has been achieved and allows for multi-scale, whole-device modeling of plasma experiments. These code coupling results will be presented. F-TRIDYN has been further upgraded with an alternative, statistical model of surface roughness. The statistical model is significantly faster than and compares favorably to the fractal model. Additionally, the statistical model compares well to alternative computational surface roughness models and experiments. Theoretical links between the fractal and statistical models are made, and further connections to experimental measurements of surface roughness are explored. This work was supported by the PSI-SciDAC Project funded by the U.S. Department of Energy through contract DOE-DE-SC0008658.

Health-Related Behaviors and Academic Achievement Among High School Students - United States, 2015.

PubMed

Rasberry, Catherine N; Tiu, Georgianne F; Kann, Laura; McManus, Tim; Michael, Shannon L; Merlo, Caitlin L; Lee, Sarah M; Bohm, Michele K; Annor, Francis; Ethier, Kathleen A

2017-09-08

Studies have shown links between educational outcomes such as letter grades, test scores, or other measures of academic achievement, and health-related behaviors (1-4). However, as reported in a 2013 systematic review, many of these studies have used samples that are not nationally representative, and quite a few studies are now at least 2 decades old (1). To update the relevant data, CDC analyzed results from the 2015 national Youth Risk Behavior Survey (YRBS), a biennial, cross-sectional, school-based survey measuring health-related behaviors among U.S. students in grades 9-12. Analyses assessed relationships between academic achievement (i.e., self-reported letter grades in school) and 30 health-related behaviors (categorized as dietary behaviors, physical activity, sedentary behaviors, substance use, sexual risk behaviors, violence-related behaviors, and suicide-related behaviors) that contribute to leading causes of morbidity and mortality among adolescents in the United States (5). Logistic regression models controlling for sex, race/ethnicity, and grade in school found that students who earned mostly A's, mostly B's, or mostly C's had statistically significantly higher prevalence estimates for most protective health-related behaviors and significantly lower prevalence estimates for most health-related risk behaviors than did students with mostly D's/F's. These findings highlight the link between health-related behaviors and education outcomes, suggesting that education and public health professionals can find their respective education and health improvement goals to be mutually beneficial. Education and public health professionals might benefit from collaborating to achieve both improved education and health outcomes for youths.

Pitfalls in statistical landslide susceptibility modelling

NASA Astrophysics Data System (ADS)

Schröder, Boris; Vorpahl, Peter; Märker, Michael; Elsenbeer, Helmut

2010-05-01

The use of statistical methods is a well-established approach to predict landslide occurrence probabilities and to assess landslide susceptibility. This is achieved by applying statistical methods relating historical landslide inventories to topographic indices as predictor variables. In our contribution, we compare several new and powerful methods developed in machine learning and well-established in landscape ecology and macroecology for predicting the distribution of shallow landslides in tropical mountain rainforests in southern Ecuador (among others: boosted regression trees, multivariate adaptive regression splines, maximum entropy). Although these methods are powerful, we think it is necessary to follow a basic set of guidelines to avoid some pitfalls regarding data sampling, predictor selection, and model quality assessment, especially if a comparison of different models is contemplated. We therefore suggest to apply a novel toolbox to evaluate approaches to the statistical modelling of landslide susceptibility. Additionally, we propose some methods to open the "black box" as an inherent part of machine learning methods in order to achieve further explanatory insights into preparatory factors that control landslides. Sampling of training data should be guided by hypotheses regarding processes that lead to slope failure taking into account their respective spatial scales. This approach leads to the selection of a set of candidate predictor variables considered on adequate spatial scales. This set should be checked for multicollinearity in order to facilitate model response curve interpretation. Model quality assesses how well a model is able to reproduce independent observations of its response variable. This includes criteria to evaluate different aspects of model performance, i.e. model discrimination, model calibration, and model refinement. In order to assess a possible violation of the assumption of independency in the training samples or a possible

Statistical process management: An essential element of quality improvement

NASA Astrophysics Data System (ADS)

Buckner, M. R.

Successful quality improvement requires a balanced program involving the three elements that control quality: organization, people and technology. The focus of the SPC/SPM User's Group is to advance the technology component of Total Quality by networking within the Group and by providing an outreach within Westinghouse to foster the appropriate use of statistic techniques to achieve Total Quality. SPM encompasses the disciplines by which a process is measured against its intrinsic design capability, in the face of measurement noise and other obscuring variability. SPM tools facilitate decisions about the process that generated the data. SPM deals typically with manufacturing processes, but with some flexibility of definition and technique it accommodates many administrative processes as well. The techniques of SPM are those of Statistical Process Control, Statistical Quality Control, Measurement Control, and Experimental Design. In addition, techniques such as job and task analysis, and concurrent engineering are important elements of systematic planning and analysis that are needed early in the design process to ensure success. The SPC/SPM User's Group is endeavoring to achieve its objectives by sharing successes that have occurred within the member's own Westinghouse department as well as within other US and foreign industry. In addition, failures are reviewed to establish lessons learned in order to improve future applications. In broader terms, the Group is interested in making SPM the accepted way of doing business within Westinghouse.

Optimized Clustering Estimators for BAO Measurements Accounting for Significant Redshift Uncertainty

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ross, Ashley J.; Banik, Nilanjan; Avila, Santiago

2017-05-15

We determine an optimized clustering statistic to be used for galaxy samples with significant redshift uncertainty, such as those that rely on photometric redshifts. To do so, we study the BAO information content as a function of the orientation of galaxy clustering modes with respect to their angle to the line-of-sight (LOS). The clustering along the LOS, as observed in a redshift-space with significant redshift uncertainty, has contributions from clustering modes with a range of orientations with respect to the true LOS. For redshift uncertaintymore » $$\\sigma_z \\geq 0.02(1+z)$$ we find that while the BAO information is confined to transverse clustering modes in the true space, it is spread nearly evenly in the observed space. Thus, measuring clustering in terms of the projected separation (regardless of the LOS) is an efficient and nearly lossless compression of the signal for $$\\sigma_z \\geq 0.02(1+z)$$. For reduced redshift uncertainty, a more careful consideration is required. We then use more than 1700 realizations of galaxy simulations mimicking the Dark Energy Survey Year 1 sample to validate our analytic results and optimized analysis procedure. We find that using the correlation function binned in projected separation, we can achieve uncertainties that are within 10 per cent of of those predicted by Fisher matrix forecasts. We predict that DES Y1 should achieve a 5 per cent distance measurement using our optimized methods. We expect the results presented here to be important for any future BAO measurements made using photometric redshift data.« less

An operational definition of a statistically meaningful trend.

PubMed

Bryhn, Andreas C; Dimberg, Peter H

2011-04-28

Linear trend analysis of time series is standard procedure in many scientific disciplines. If the number of data is large, a trend may be statistically significant even if data are scattered far from the trend line. This study introduces and tests a quality criterion for time trends referred to as statistical meaningfulness, which is a stricter quality criterion for trends than high statistical significance. The time series is divided into intervals and interval mean values are calculated. Thereafter, r(2) and p values are calculated from regressions concerning time and interval mean values. If r(2) ≥ 0.65 at p ≤ 0.05 in any of these regressions, then the trend is regarded as statistically meaningful. Out of ten investigated time series from different scientific disciplines, five displayed statistically meaningful trends. A Microsoft Excel application (add-in) was developed which can perform statistical meaningfulness tests and which may increase the operationality of the test. The presented method for distinguishing statistically meaningful trends should be reasonably uncomplicated for researchers with basic statistics skills and may thus be useful for determining which trends are worth analysing further, for instance with respect to causal factors. The method can also be used for determining which segments of a time trend may be particularly worthwhile to focus on.

Statistical algorithms improve accuracy of gene fusion detection

PubMed Central

Hsieh, Gillian; Bierman, Rob; Szabo, Linda; Lee, Alex Gia; Freeman, Donald E.; Watson, Nathaniel; Sweet-Cordero, E. Alejandro

2017-01-01

Abstract Gene fusions are known to play critical roles in tumor pathogenesis. Yet, sensitive and specific algorithms to detect gene fusions in cancer do not currently exist. In this paper, we present a new statistical algorithm, MACHETE (Mismatched Alignment CHimEra Tracking Engine), which achieves highly sensitive and specific detection of gene fusions from RNA-Seq data, including the highest Positive Predictive Value (PPV) compared to the current state-of-the-art, as assessed in simulated data. We show that the best performing published algorithms either find large numbers of fusions in negative control data or suffer from low sensitivity detecting known driving fusions in gold standard settings, such as EWSR1-FLI1. As proof of principle that MACHETE discovers novel gene fusions with high accuracy in vivo, we mined public data to discover and subsequently PCR validate novel gene fusions missed by other algorithms in the ovarian cancer cell line OVCAR3. These results highlight the gains in accuracy achieved by introducing statistical models into fusion detection, and pave the way for unbiased discovery of potentially driving and druggable gene fusions in primary tumors. PMID:28541529

Juvenile Psychopathic Personality Traits are Associated with Poor Reading Achievement

PubMed Central

DeLisi, Matt; Beaver, Kevin M.; Wexler, Jade; Barth, Amy; Fletcher, Jack

2011-01-01

The current study sought to further the understanding of the linkage between maladaptive behavior and cognitive problems by examining the relations between psychopathic personality traits and reading comprehension performance. Data were derived from a study of 432 predominately African-American and Hispanic middle-school students. Dependent variables consisted of three measures of reading comprehension. Psychopathy measures included the Inventory of Callous-Unemotional traits (ICU—teacher rated) and the self-reported Youth Psychopathic traits Inventory (YPI). Findings from regression models indicated that self-report and teacher ratings of psychopathy were statistically significant inverse predictors of reading performance. Specifically, affective facets of psychopathy were potent predictors of reading comprehension over and above ADHD, IQ, and an impulsivity component of psychopathy. Study results extend the utility of psychopathy construct generally and affective traits specifically to reading achievement, which has broad implications. Findings are discussed with respect to future research and prevention. PMID:20957434

Effects of individualized assignments on biology achievement

NASA Astrophysics Data System (ADS)

Kremer, Philip L.

A pretest-posttest, randomized, two groups, experimental, factorial design compared effects of detailed and nondetailed assignments on biology achievement over seven and a half months. Detailed assignments (favoring field independence and induction) employed block diagrams and stepwise directions. Nondetailed assignments (favoring field dependence and deduction) virtually lacked these. The accessible population was 101 tenth grade preparatory school male students. The 95 students enrolled in first year biology constituted the sample. Two by three ANOVA was done on residualized posttest score means of the students. Totally, the detailed students achieved significantly higher than the nondetailed students. This significantly higher achievement was only true of detailed students in the middle thirds of the deviation intelligence quotient (DIQ) range and of the grade point average (G.P.A.) range after the breakdown into upper, middle, and lower thirds of intellectual capability (ability and achievement). The upper third detailed DIQ grouping indirectly achieved higher than its peers, whereas the lower detailed DIQ third achieved lower than its peers. Thus, high capability students apparently benefit from flow and block diagrams, inductions, field independence, and high structure, whereas low capability students may be hindered by these.

Mutual interference between statistical summary perception and statistical learning.

PubMed

Zhao, Jiaying; Ngo, Nhi; McKendrick, Ryan; Turk-Browne, Nicholas B

2011-09-01

The visual system is an efficient statistician, extracting statistical summaries over sets of objects (statistical summary perception) and statistical regularities among individual objects (statistical learning). Although these two kinds of statistical processing have been studied extensively in isolation, their relationship is not yet understood. We first examined how statistical summary perception influences statistical learning by manipulating the task that participants performed over sets of objects containing statistical regularities (Experiment 1). Participants who performed a summary task showed no statistical learning of the regularities, whereas those who performed control tasks showed robust learning. We then examined how statistical learning influences statistical summary perception by manipulating whether the sets being summarized contained regularities (Experiment 2) and whether such regularities had already been learned (Experiment 3). The accuracy of summary judgments improved when regularities were removed and when learning had occurred in advance. In sum, calculating summary statistics impeded statistical learning, and extracting statistical regularities impeded statistical summary perception. This mutual interference suggests that statistical summary perception and statistical learning are fundamentally related.

Data-Mining Techniques in Detecting Factors Linked to Academic Achievement

ERIC Educational Resources Information Center

Martínez Abad, Fernando; Chaparro Caso López, Alicia A.

2017-01-01

In light of the emergence of statistical analysis techniques based on data mining in education sciences, and the potential they offer to detect non-trivial information in large databases, this paper presents a procedure used to detect factors linked to academic achievement in large-scale assessments. The study is based on a non-experimental,…

Fostering Dental Students' Academic Achievements and Reflection Skills Through Clinical Peer Assessment and Feedback.

PubMed

Tricio, Jorge A; Woolford, Mark J; Escudier, Michael P

2016-08-01

Peer assessment is increasingly being encouraged to enhance dental students' learning. The aim of this study was to evaluate the educational impact in terms of academic achievements and reflective thinking of a formative prospective peer assessment and feedback protocol. Volunteer final-year dental students at King's College London Dental Institute, UK, received training on peer assessment, peer feedback, and self-reflection. At the beginning (baseline) and end (resultant) of the 2012-13 academic year, 86 students (55% of the year group) completed a reflection questionnaire (RQ). Sixty-eight of those students used a modified Direct Observation of Procedural Skills (DOPS) as a framework for peer assessment and peer feedback during a complete academic year. End-of-year, high-stakes examination grades and RQ scores from the participants and nonparticipants were statistically compared. The participants completed 576 peer DOPS. Those 22 students who peer assessed each other ≥10 times exhibited highly statistically significant differences and powerful positive effect sizes in their high-stakes exam grades (p=0.0001, d=0.74) and critical reflection skills (p=0.005, d=1.41) when compared to those who did not assess one another. Furthermore, only the same 22 students showed a statistically significant increase and positive effect size in their critical reflection skills from baseline to resultant (p=0.003, d=1.04). The results of this study suggest that the protocol used has the potential to impact dental students' academic and reflection skills, provided it is practiced in ten or more peer encounters and ensuring peer feedback is provided followed by self-reflection.

Spectral and cross-spectral analysis of uneven time series with the smoothed Lomb-Scargle periodogram and Monte Carlo evaluation of statistical significance

NASA Astrophysics Data System (ADS)

Pardo-Igúzquiza, Eulogio; Rodríguez-Tovar, Francisco J.

2012-12-01

Many spectral analysis techniques have been designed assuming sequences taken with a constant sampling interval. However, there are empirical time series in the geosciences (sediment cores, fossil abundance data, isotope analysis, …) that do not follow regular sampling because of missing data, gapped data, random sampling or incomplete sequences, among other reasons. In general, interpolating an uneven series in order to obtain a succession with a constant sampling interval alters the spectral content of the series. In such cases it is preferable to follow an approach that works with the uneven data directly, avoiding the need for an explicit interpolation step. The Lomb-Scargle periodogram is a popular choice in such circumstances, as there are programs available in the public domain for its computation. One new computer program for spectral analysis improves the standard Lomb-Scargle periodogram approach in two ways: (1) It explicitly adjusts the statistical significance to any bias introduced by variance reduction smoothing, and (2) it uses a permutation test to evaluate confidence levels, which is better suited than parametric methods when neighbouring frequencies are highly correlated. Another novel program for cross-spectral analysis offers the advantage of estimating the Lomb-Scargle cross-periodogram of two uneven time series defined on the same interval, and it evaluates the confidence levels of the estimated cross-spectra by a non-parametric computer intensive permutation test. Thus, the cross-spectrum, the squared coherence spectrum, the phase spectrum, and the Monte Carlo statistical significance of the cross-spectrum and the squared-coherence spectrum can be obtained. Both of the programs are written in ANSI Fortran 77, in view of its simplicity and compatibility. The program code is of public domain, provided on the website of the journal (http://www.iamg.org/index.php/publisher/articleview/frmArticleID/112/). Different examples (with simulated and

The effect of normalization of Partial Directed Coherence on the statistical assessment of connectivity patterns: a simulation study.

PubMed

Toppi, J; Petti, M; Vecchiato, G; Cincotti, F; Salinari, S; Mattia, D; Babiloni, F; Astolfi, L

2013-01-01

Partial Directed Coherence (PDC) is a spectral multivariate estimator for effective connectivity, relying on the concept of Granger causality. Even if its original definition derived directly from information theory, two modifies were introduced in order to provide better physiological interpretations of the estimated networks: i) normalization of the estimator according to rows, ii) squared transformation. In the present paper we investigated the effect of PDC normalization on the performances achieved by applying the statistical validation process on investigated connectivity patterns under different conditions of Signal to Noise ratio (SNR) and amount of data available for the analysis. Results of the statistical analysis revealed an effect of PDC normalization only on the percentages of type I and type II errors occurred by using Shuffling procedure for the assessment of connectivity patterns. No effects of the PDC formulation resulted on the performances achieved during the validation process executed instead by means of Asymptotic Statistic approach. Moreover, the percentages of both false positives and false negatives committed by Asymptotic Statistic are always lower than those achieved by Shuffling procedure for each type of normalization.

Mindmapping: Its effects on student achievement in high school biology

NASA Astrophysics Data System (ADS)

Cunningham, Glennis Edge

The primary goal of schools is to promote the highest degree of learning possible. Yet teachers spend the majority of their time engaged in lecturing while students spend the majority of their time passively present (Cawelti, 1997, Grinder, 1991; Jackson & Davis, 2000; Jenkins, 1996). Helping students develop proficiency in learning, which translates into using that expertise to construct knowledge in subject domains, is a crucial goal of education. Students need exposure to teaching and learning practices that prepare them for both the classroom and their places in the future workforce (Ettinger, 1998; Longley, Goodchild, Maguire, & Rhind, 2001; NRC, 1996; Texley & Wild, 1996). The purpose of this study was to determine if achievement in high school science courses could be enhanced utilizing mindmapping. The subjects were primarily 9th and 10th graders (n = 147) at a suburban South Texas high school. A pretest-posttest control group design was selected to determine the effects of mindmapping on student achievement as measured by a teacher-developed, panel-validated instrument. Follow-up interviews were conducted with the teacher and a purposive sample of students (n = 7) to determine their perceptions of mindmapping and its effects on teaching and learning. Mindmapping is a strategy for visually displaying large amounts of conceptual, hierarchical information in a concise, organized, and accessible format. Mindmaps arrange information similar to that found on the traditional topic outline into colorful spatial displays that offer the user a view of the "forest" as well as the "trees" (Hyerle, 1996; Wandersee, 1990b). An independent samples t-test and a one-way analysis of covariance (ANCOVA) determined no significant difference in achievement between the groups. The experimental group improved in achievement at least as much as the control group. Several factors may have played a role in the lack of statistically significant results. These factors include the

Comparisons of Student Achievement Levels by District Performance and Poverty. ACT Research Report Series 2016-11

ERIC Educational Resources Information Center

Dougherty, Chrys; Shaw, Teresa

2016-01-01

This report looks at student achievement levels in Arkansas school districts disaggregated by district poverty and by the district's performance relative to other districts. We estimated district performance statistics by subject and grade level (4, 8, and 11-12) for longitudinal student cohorts, using statistical models that adjusted for district…

Effects of basic character design and animation concepts using the flipped learning and project-based learning approach on learning achievement and creative thinking of higher education students

NASA Astrophysics Data System (ADS)

Autapao, Kanyarat; Minwong, Panthul

2018-01-01

Creative thinking was an important learning skill in the 21st Century via learning and innovation to promote students' creative thinking and working with others and to construct innovation. This is one of the important skills that determine the readiness of the participants to step into the complex society. The purposes of this research were 1) to compare the learning achievement of students after using basic character design and animation concepts using the flipped learning and project-based learning and 2) to make a comparison students' creative thinking between pretest and posttest. The populations were 29 students in Multimedia Technology program at Thepsatri Rajabhat University in the 2nd semester of the academic year 2016. The experimental instruments were lesson plans of basic character design and animation concepts using the flipped learning and project based learning. The data collecting instrument was creative thinking test. The data were analyzed by the arithmetic mean, standard deviation and The Wilcoxon Matched Pairs Signed-Ranks Test. The results of this research were 1) the learning achievement of students were statistically significance of .01 level and 2) the mean score of student's creativity assessment were statistically significance of .05 level. When considering all of 11 KPIs, showed that respondents' post-test mean scores higher than pre-test. And 5 KPIs were statistically significance of .05 level, consist of Originality, Fluency, Elaboration, Resistance to Premature Closure, and Intrinsic Motivation. It's were statistically significance of .042, .004, .049, .024 and .015 respectively. And 6 KPIs were non-statistically significant, include of Flexibility, Tolerance of Ambiguity, Divergent Thinking, Convergent Thinking, Risk Taking, and Extrinsic Motivation. The findings revealed that the flipped learning and project based learning provided students the freedom to simply learn on their own aptitude. When working together with project

Ethnic Group Differences in Educational Achievement in Fiji.

ERIC Educational Resources Information Center

Basow, Susan A.

1984-01-01

No significant relationship was found between ethnic Fijian 10th graders' scores on tests of Competitiveness, Mastery, Work Orientation, Personal Unconcern, and Self Esteem and educational achievement. It is concluded that factors relating to the meaning of achievement are more important in understanding ethnic group achievement differences in…

The effects of integrated mathematics/science curriculum and instruction on mathematics achievement and student attitudes in grade six

NASA Astrophysics Data System (ADS)

Hill, Mary Denise

The purpose of this study was to determine whether integrating mathematics and science curriculum and teaching practices significantly improves achievement in mathematics and attitudes towards mathematics among sixth grade students in South Texas. The study was conducted during the 2001--2002 school year. A causal-comparative ex post facto research design was used to explore the effects of integrated mathematics and science classrooms compared to classrooms of traditional, isolated mathematics and science teaching practices on student achievement and student attitudes. Achievement was based on the Spring 2002 Mathematics portion of the standardized Texas Assessment of Academic Skills (TAAS) Texas Learning Index (TLI) scores and individual student's mathematics Grade Point Average (GPA). Measurement of student attitudes was based on the results of the Integrated Mathematics Attitudinal Survey (IMAS), created by the researcher for this study. The sample population included 349 Grade 6 mathematics students attending one middle school involved in a pilot program utilizing integrated mathematics/science curriculum and teaching practices in a South Texas urban school district. The research involved 337 of the 349 sixth grade students to study the effects of mathematics/science curriculum and teaching practices on achievement and 207 of the 349 sixth grade students to study the effects of mathematics/science curriculum on attitudes concerning mathematics. The data were analyzed using chi square analyses, independent samples t-tests, and the analysis of variance (ANOVA). Statistical significance was determined at the .05 level of significance. Significant relationships were found when analyzing the proficiency of mathematics skills and individual growth of mathematics achievement. Chi square analyses indicated that the students in the integrated mathematics/science classrooms were more likely to exhibit individual growth and proficiency of mathematics skills based on the

Study the relationship between medical sciences students’ self-esteem and academic achievement of Guilan university of medical sciences

PubMed Central

Jirdehi, Maryam Mirzaee; Asgari, Fariba; Tabari, Rasool; Leyli, Ehsan Kazemnejad

2018-01-01

BACKGROUND: Achievement of productivity and improvement of quality in the educational system is the effective, influential factors for countries development. Academic achievement is the main objective of the training program and the most important concerns of teachers, education officials, and university Student's families. Self-esteem is one of the factors affecting student academic achievement. This study is aimed to investigate the relationship between self-esteem and academic achievement in Medical Sciences students of in 2014–2015. SUBJECTS AND METHODS: This is a descriptive–correlational study. In this study, 537 university students were selected using random stratified sampling method from Guilan University of Medical Sciences in 2014–2015. Data were collected using the standard self-esteem questionnaire of Cooper Smith consisting of four elements (general, social, familial, and educational) and a demographic questionnaire. Data were analyzed using SPSS software version 21 and descriptive statistics such as Spearman correlation and Logistic Regression. RESULTS: The results indicated a significant relationship between grade point average and educational self-esteem (P = 0.002, r = 0.135) and global self-esteem (P = 0.02, r = 0.102). There was also a significant relationship between composite Index educational status and general self-esteem (P = 0.019, r = 0.102) and academic achievement (P = 0.007, r = 0.116) and global self-esteem (P = 0.020, r = 0.102). CONCLUSIONS: According to the results, the highest mean score of self-esteem was related to the familial element, and the lowest average was in terms of social self-esteem, therefore, given the importance and necessity of self-esteem in academic achievement, strengthening of all aspects of self-esteem is suggested. PMID:29693033

Study the relationship between medical sciences students' self-esteem and academic achievement of Guilan university of medical sciences.

PubMed

Jirdehi, Maryam Mirzaee; Asgari, Fariba; Tabari, Rasool; Leyli, Ehsan Kazemnejad

2018-01-01

Achievement of productivity and improvement of quality in the educational system is the effective, influential factors for countries development. Academic achievement is the main objective of the training program and the most important concerns of teachers, education officials, and university Student's families. Self-esteem is one of the factors affecting student academic achievement. This study is aimed to investigate the relationship between self-esteem and academic achievement in Medical Sciences students of in 2014-2015. This is a descriptive-correlational study. In this study, 537 university students were selected using random stratified sampling method from Guilan University of Medical Sciences in 2014-2015. Data were collected using the standard self-esteem questionnaire of Cooper Smith consisting of four elements (general, social, familial, and educational) and a demographic questionnaire. Data were analyzed using SPSS software version 21 and descriptive statistics such as Spearman correlation and Logistic Regression. The results indicated a significant relationship between grade point average and educational self-esteem ( P = 0.002, r = 0.135) and global self-esteem ( P = 0.02, r = 0.102). There was also a significant relationship between composite Index educational status and general self-esteem ( P = 0.019, r = 0.102) and academic achievement ( P = 0.007, r = 0.116) and global self-esteem ( P = 0.020, r = 0.102). According to the results, the highest mean score of self-esteem was related to the familial element, and the lowest average was in terms of social self-esteem, therefore, given the importance and necessity of self-esteem in academic achievement, strengthening of all aspects of self-esteem is suggested.

Statistical inference of protein structural alignments using information and compression.

PubMed

Collier, James H; Allison, Lloyd; Lesk, Arthur M; Stuckey, Peter J; Garcia de la Banda, Maria; Konagurthu, Arun S

2017-04-01

Structural molecular biology depends crucially on computational techniques that compare protein three-dimensional structures and generate structural alignments (the assignment of one-to-one correspondences between subsets of amino acids based on atomic coordinates). Despite its importance, the structural alignment problem has not been formulated, much less solved, in a consistent and reliable way. To overcome these difficulties, we present here a statistical framework for the precise inference of structural alignments, built on the Bayesian and information-theoretic principle of Minimum Message Length (MML). The quality of any alignment is measured by its explanatory power-the amount of lossless compression achieved to explain the protein coordinates using that alignment. We have implemented this approach in MMLigner , the first program able to infer statistically significant structural alignments. We also demonstrate the reliability of MMLigner 's alignment results when compared with the state of the art. Importantly, MMLigner can also discover different structural alignments of comparable quality, a challenging problem for oligomers and protein complexes. Source code, binaries and an interactive web version are available at http://lcb.infotech.monash.edu.au/mmligner . arun.konagurthu@monash.edu. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Dental Students' Educational Achievement in Relation to Their Learning Styles: A Cross-Sectional Study in Iran.

PubMed

Hosseini, Seyed Masoud; Amery, Hamideh; Emadzadeh, Ali; Babazadeh, Saber

2015-02-24

In recent decades, many studies have been carried out on the importance of Kolb experiential learning theory (ELT) in teaching-learning processes and its effect on learning outcomes. However, some experts have criticized the Kolb theory and argue that there are some ambiguities on the validity of the theory as an important predictor of achievement. This study has been carried out on dental students' educational achievement in relation to their dominant learning styles based on Kolb theory in Mashhad University of Medical Sciences (Iran). In a cross sectional study, Kolb Learning Style Inventory (LSI Ver. 3.1) as well as a questionnaire containing students' demographic data, academic achievement marks including grade point average (GPA), theoretical and practical courses marks, and the comprehensive basic sciences exam (CBSE) scores were administered on a purposive sample of 162 dental students who had passed their comprehensive basic sciences exam. Educational achievement data were analyzed in relation to students' dominant learning styles, using descriptive and analytical statistics including χ2, Kruskal-Wallis and two-way ANOVA tests. The dominant learning styles of students were Assimilating (53.1%), Converging (24.1%), Diverging (14.2%) and Accommodating (8.6%). Although, the students with Assimilating and Converging learning styles had a better performance on their educational achievement, there was no significant relationship between educational achievement and dominant learning style (P≥0.05). Findings support that the dominant learning style is not exclusively an essential factor to predict educational achievement. Rather, it shows learning preferences of students that may be considered in designing learning opportunities by the teachers.

[Statistics for statistics?--Thoughts about psychological tools].

PubMed

Berger, Uwe; Stöbel-Richter, Yve

2007-12-01

Statistical methods take a prominent place among psychologists' educational programs. Being known as difficult to understand and heavy to learn, students fear of these contents. Those, who do not aspire after a research carrier at the university, will forget the drilled contents fast. Furthermore, because it does not apply for the work with patients and other target groups at a first glance, the methodological education as a whole was often questioned. For many psychological practitioners the statistical education makes only sense by enforcing respect against other professions, namely physicians. For the own business, statistics is rarely taken seriously as a professional tool. The reason seems to be clear: Statistics treats numbers, while psychotherapy treats subjects. So, does statistics ends in itself? With this article, we try to answer the question, if and how statistical methods were represented within the psychotherapeutical and psychological research. Therefore, we analyzed 46 Originals of a complete volume of the journal Psychotherapy, Psychosomatics, Psychological Medicine (PPmP). Within the volume, 28 different analyse methods were applied, from which 89 per cent were directly based upon statistics. To be able to write and critically read Originals as a backbone of research, presumes a high degree of statistical education. To ignore statistics means to ignore research and at least to reveal the own professional work to arbitrariness.

A study of the relationships between "highly qualified" status, instructional practices, and students' science achievement in three high poverty Louisiana school systems

NASA Astrophysics Data System (ADS)

Clayton, Michelle

Using a mixed methods research design, the author examined the relationships between "highly qualified" status, instructional practices, and students' science achievement for six third grade teachers in three high poverty Louisiana school systems. The study analyzed qualitative and quantitative data for three science classes taught by "highly qualified" teachers and three science classes taught by "non-highly qualified" teachers. The qualitative portion of the study was conducted through classroom observations, teacher interviews, and lesson plan reviews. The qualitative data was coded and triangulated to determine whether the instructional practices of each teacher were more "teacher-centered" or "student-centered." The qualitative data analysis indicated various patterns and consistencies in the instructional practices used by the "highly qualified" and "non-highly qualified" teachers selected for this study. The quantitative portion of the study involved analysis of the students' science achievement data for the six third grade science teachers selected for the study. Science achievement was measured by the third grade Integrated Louisiana Education Assessment Program (iLEAP) scores. A two-way ANOVA indicated that there were statistically significant differences in the mean scores of the three high poverty Louisiana school systems as well as the students taught by "highly qualified" and "non-highly qualified" teachers and the interactions between the two: F(2, 123) = 46.99, p < 0.01; F(1, 123) = 4.54, p = 0.035; F(2, 123) = 3.73, p = 0.027. A separate one-way ANOVA indicated that statistically significant differences existed between the six participating teachers in the study: F (5, 123) = 20.386, p < 0.01). Tukey's HSD post-hoc tests and homogeneous subset analyses were conducted in order to determine which teachers' scores significantly differed from each other.

Testing a Model of the Relationship of Demographic, Affective, and Fitness Variables to Academic Achievement among Non-Science Majors at an Independent University

NASA Astrophysics Data System (ADS)

Dutra, Andrew Martin

The purpose of this study was to determine the relationship of specific attributes of college students to their academic achievement at an independent university in central Florida. Academic achievement was measured as the numeric score on the final exam in a survey-of-science course (EDS 1032) required for non-science majors. Attribute sets included personological, affective, and fitness variables. A hypothesized diagram of the direct and indirect effects among these attributes relative to academic achievement was developed and tested using data collected Spring 2014 from 168 students in four sections of EDS 1032 at Florida Institute of Technology. Multiple regression results revealed that 19% of the variance in a students' academic achievement was due to the influence of these three sets of research factors; this was found to be statistically significant. The results of mediation analyses also indicated that three variables had significant direct effects on academic achievement, namely gender, number of academic credits, and sports motivation. In addition, gender had a significant indirect effect on academic achievement via stress, and the number of academic credits had a significant indirect effect on academic achievement via sports motivation. These findings indicated that female students scored roughly six points higher than male students on this final exam. Also, gender's influence on academic achievement was partially attributable to the student's level of stress (e.g., male students with high levels of stress had lower grades on this final exam than female students with the same level of stress). In addition, it was found that students taking more academic credits were likely to score higher on this final exam than those students taking fewer credits. Further, as students' level of sports amotivation increased, the strength of the relationship between the number of student academic credits and academic achievement decreased. These results support Self

University and Student Segmentation: Multilevel Latent-Class Analysis of Students' Attitudes towards Research Methods and Statistics

ERIC Educational Resources Information Center

Mutz, Rudiger; Daniel, Hans-Dieter

2013-01-01

Background: It is often claimed that psychology students' attitudes towards research methods and statistics affect course enrolment, persistence, achievement, and course climate. However, the inter-institutional variability has been widely neglected in the research on students' attitudes towards research methods and statistics, but it is important…

Significant achievements in the planetary geology program

NASA Technical Reports Server (NTRS)

Head, J. W. (Editor)

1984-01-01

Recent developments in planetology research are summarized. Important developments are summarized in topics ranging from solar system evolution, comparative planetology, and geologic processes active on other planetary bodies, to techniques and instrument development for exploration.

The Achievement Gap: Factors That Influenced the Achievement of Successful Black Students

ERIC Educational Resources Information Center

Morton, Kwame R., Sr.

2011-01-01

The academic underperformance of Black students when compared to their White peers has confounded educators nationwide. This discrepancy in academic performance commonly referred to as the achievement gap has become a national crisis which has led to one of the most significant educational reforms undertaken in the United States of America in the…

Statistical strategy for anisotropic adventitia modelling in IVUS.

PubMed

Gil, Debora; Hernández, Aura; Rodriguez, Oriol; Mauri, Josepa; Radeva, Petia

2006-06-01

Vessel plaque assessment by analysis of intravascular ultrasound sequences is a useful tool for cardiac disease diagnosis and intervention. Manual detection of luminal (inner) and media-adventitia (external) vessel borders is the main activity of physicians in the process of lumen narrowing (plaque) quantification. Difficult definition of vessel border descriptors, as well as, shades, artifacts, and blurred signal response due to ultrasound physical properties trouble automated adventitia segmentation. In order to efficiently approach such a complex problem, we propose blending advanced anisotropic filtering operators and statistical classification techniques into a vessel border modelling strategy. Our systematic statistical analysis shows that the reported adventitia detection achieves an accuracy in the range of interobserver variability regardless of plaque nature, vessel geometry, and incomplete vessel borders.

Tools for Basic Statistical Analysis

NASA Technical Reports Server (NTRS)

Luz, Paul L.

2005-01-01

Statistical Analysis Toolset is a collection of eight Microsoft Excel spreadsheet programs, each of which performs calculations pertaining to an aspect of statistical analysis. These programs present input and output data in user-friendly, menu-driven formats, with automatic execution. The following types of calculations are performed: Descriptive statistics are computed for a set of data x(i) (i = 1, 2, 3 . . . ) entered by the user. Normal Distribution Estimates will calculate the statistical value that corresponds to cumulative probability values, given a sample mean and standard deviation of the normal distribution. Normal Distribution from two Data Points will extend and generate a cumulative normal distribution for the user, given two data points and their associated probability values. Two programs perform two-way analysis of variance (ANOVA) with no replication or generalized ANOVA for two factors with four levels and three repetitions. Linear Regression-ANOVA will curvefit data to the linear equation y=f(x) and will do an ANOVA to check its significance.

Neuroanatomical correlates of the income-achievement gap.

PubMed

Mackey, Allyson P; Finn, Amy S; Leonard, Julia A; Jacoby-Senghor, Drew S; West, Martin R; Gabrieli, Christopher F O; Gabrieli, John D E

2015-06-01

In the United States, the difference in academic achievement between higher- and lower-income students (i.e., the income-achievement gap) is substantial and growing. In the research reported here, we investigated neuroanatomical correlates of this gap in adolescents (N = 58) in whom academic achievement was measured by statewide standardized testing. Cortical gray-matter volume was significantly greater in students from higher-income backgrounds (n = 35) than in students from lower-income backgrounds (n = 23), but cortical white-matter volume and total cortical surface area did not differ significantly between groups. Cortical thickness in all lobes of the brain was greater in students from higher-income than lower-income backgrounds. Greater cortical thickness, particularly in temporal and occipital lobes, was associated with better test performance. These results represent the first evidence that cortical thickness in higher- and lower-income students differs across broad swaths of the brain and that cortical thickness is related to scores on academic-achievement tests. © The Author(s) 2015.

Why publishing everything is more effective than selective publishing of statistically significant results.

PubMed

van Assen, Marcel A L M; van Aert, Robbie C M; Nuijten, Michèle B; Wicherts, Jelte M

2014-01-01

De Winter and Happee examined whether science based on selective publishing of significant results may be effective in accurate estimation of population effects, and whether this is even more effective than a science in which all results are published (i.e., a science without publication bias). Based on their simulation study they concluded that "selective publishing yields a more accurate meta-analytic estimation of the true effect than publishing everything, (and that) publishing nonreplicable results while placing null results in the file drawer can be beneficial for the scientific collective" (p.4). Using their scenario with a small to medium population effect size, we show that publishing everything is more effective for the scientific collective than selective publishing of significant results. Additionally, we examined a scenario with a null effect, which provides a more dramatic illustration of the superiority of publishing everything over selective publishing. Publishing everything is more effective than only reporting significant outcomes.

Why Publishing Everything Is More Effective than Selective Publishing of Statistically Significant Results

PubMed Central

van Assen, Marcel A. L. M.; van Aert, Robbie C. M.; Nuijten, Michèle B.; Wicherts, Jelte M.

2014-01-01

Background De Winter and Happee [1] examined whether science based on selective publishing of significant results may be effective in accurate estimation of population effects, and whether this is even more effective than a science in which all results are published (i.e., a science without publication bias). Based on their simulation study they concluded that “selective publishing yields a more accurate meta-analytic estimation of the true effect than publishing everything, (and that) publishing nonreplicable results while placing null results in the file drawer can be beneficial for the scientific collective” (p.4). Methods and Findings Using their scenario with a small to medium population effect size, we show that publishing everything is more effective for the scientific collective than selective publishing of significant results. Additionally, we examined a scenario with a null effect, which provides a more dramatic illustration of the superiority of publishing everything over selective publishing. Conclusion Publishing everything is more effective than only reporting significant outcomes. PMID:24465448

The Coopersmith Self-Esteem Inventory Related to Academic Achievement and School Behavior. Interim Research Report # 23.

ERIC Educational Resources Information Center

Rubin, Rosalyn; And Others

Scores on the Coopersmith Self-Esteem Inventory were related to scores on achievement and intelligence tests, and to socioeconomic level and to teachers' ratings of student behavior, in order to test the hypothesis that student self esteem would have a positive effect on academic achievement. There was a small but statistically significant…

Tables of Significance Points for the Variance-Weighted Kolmogorov-Smirnov Statistics.

DTIC Science & Technology

1981-02-19

neN x; 1; ( := 0 for all z Vo0 For the values of a function V: N0 IR we use both notations V(i) and vi " ii Tables of Significance Points for the...satisfying 0 < V0 < 10 and v, < Vi -i ¥i IN,* The following functions define a 4-Sheffer sequence (see (A.12)) for the derivative operator D: d i if x ɘ f(,c...S U(i ) < Ii ¥ Vi l,...,M)IMl 7 i7- 1.2. Recursions. For this section we assume p’ 1 without loss of generality.M With qn-k(x)- x n-k/(n-k)! in (A.13

The relationship between standards-based reporting systems and third-grade mathematics and science achievement

NASA Astrophysics Data System (ADS)

Prejean-Harris, Rose M.

Over the last decade, accountability has been the driving force for many changes in education in the United States. One major educational reform effort is the standards-based movement with a focus of combining a number of processes that involve aligning curriculum, instruction, assessment and feedback to specific standards that are measureable and indicative of student achievement. The purpose of this study is to determine if the type of report card is a possible predictor of third grade student achievement on standardized tests in mathematics and science for the 2012 Criterion-Referenced Competency Test (CRCT). The results of this study concluded that the difference in test scores in mathematics and science for students in the traditional report card group was not statistically significant when compared to the scores of students in the standards-based report card group when controlling for poverty level, school locale, and school district. However, students in the traditional report card group scored an average of 1.01 point higher in mathematics and 2.27 points higher in science than students in the standards-based report card group.

Assay optimization: a statistical design of experiments approach.

PubMed

Altekar, Maneesha; Homon, Carol A; Kashem, Mohammed A; Mason, Steven W; Nelson, Richard M; Patnaude, Lori A; Yingling, Jeffrey; Taylor, Paul B

2007-03-01

With the transition from manual to robotic HTS in the last several years, assay optimization has become a significant bottleneck. Recent advances in robotic liquid handling have made it feasible to reduce assay optimization timelines with the application of statistically designed experiments. When implemented, they can efficiently optimize assays by rapidly identifying significant factors, complex interactions, and nonlinear responses. This article focuses on the use of statistically designed experiments in assay optimization.

Achievement orientation and fear of success in Asian American college students.

PubMed

Lew, A S; Allen, R; Papouchis, N; Ritzler, B