Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Journal

Bias

Discipline
Institution
Publication Year
Publication

Articles 31 - 38 of 38

Full-Text Articles in Physical Sciences and Mathematics

Utility Of Weights For Weighted Kappa As A Measure Of Interrater Agreement On Ordinal Scale, Moonseong Heo May 2008

Utility Of Weights For Weighted Kappa As A Measure Of Interrater Agreement On Ordinal Scale, Moonseong Heo

Journal of Modern Applied Statistical Methods

Kappa statistics, unweighted or weighted, are widely used for assessing interrater agreement. The weights of the weighted kappa statistics in particular are defined in terms of absolute and squared distances in ratings between raters. It is proposed that those weights can be used for assessment of interrater agreements. A closed form expectations and variances of the agreement statistics referred to as AI1 and AI2, functions of absolute and squared distances in ratings between two raters, respectively, are obtained. AI1 and AI2 are compared with the weighted and unweighted kappa statistics in …


Using Exploratory Factor Analysis For Locating Invariant Referents In Factor Invariance Studies, W. Holmes Finch, Brian F. French May 2008

Using Exploratory Factor Analysis For Locating Invariant Referents In Factor Invariance Studies, W. Holmes Finch, Brian F. French

Journal of Modern Applied Statistical Methods

Model identification in multi-group confirmatory factor analysis (MCFA) requires an equality constraint of referent variables across groups. Invariance assumption violations make it difficult to locate parameters that actually differ. Suggested procedures for locating invariant referents are cumbersome, complex, and provide imperfect results. Exploratory factor analysis (EFA) may be an alternative because of its ease of use, yet empirical evaluation of its effectiveness is lacking. EFAs accuracy for distinguishing invariant from non-invariant referents was examined.


Applications Of Some Improved Estimators In Linear Regression, B. M. Golam Kibria Nov 2005

Applications Of Some Improved Estimators In Linear Regression, B. M. Golam Kibria

Journal of Modern Applied Statistical Methods

The problem of estimation of the regression coefficients under multicollinearity situation for the restricted linear model is discussed. Some improve estimators are considered, including the unrestricted ridge regression estimator (URRE), restricted ridge regression estimator (RRRE), shrinkage restricted ridge regression estimator (SRRRE), preliminary test ridge regression estimator (PTRRE), and restricted Liu estimator (RLIUE). The were compared based on the sampling variance-covariance criterion. The RRRE dominates other ridge estimators when the restriction does or does not hold. A numerical example was provided. The RRRE performed equivalently or better than the RLIUE in the sense of having smaller sampling variance.


Not All Effects Are Created Equal: A Rejoinder To Sawilowsky, J. Kyle Roberts, Robin K. Henson May 2003

Not All Effects Are Created Equal: A Rejoinder To Sawilowsky, J. Kyle Roberts, Robin K. Henson

Journal of Modern Applied Statistical Methods

In the continuing debate over the use and utility of effect sizes, more discussion often helps to both clarify and syncretize methodological views. Here, further defense is given of Roberts & Henson (2002) in terms of measuring bias in Cohen’s d, and a rejoinder to Sawilowsky (2003) is presented.


Exploration Of Distributions Of Ratio Of Partial Sum Of Sample Eigenvalues When All Population Eigenvalues Are The Same, Moonseong Heo Nov 2002

Exploration Of Distributions Of Ratio Of Partial Sum Of Sample Eigenvalues When All Population Eigenvalues Are The Same, Moonseong Heo

Journal of Modern Applied Statistical Methods

This paper explores empirically the first two moments of ratio of the partial sum of the first two sample eigenvalues to the sum of all eigenvalues when the population eigenvalues of a covariance matrix are all the same. Estimation of the first two moments can be practically crucial in assessing non-randomness of observed patterns on planar graphical displays based on lower rank approximations of data matrices. For derivation of the moments, exact and large sample asymptotic distributions of the sample ratios are reviewed but neither can be applicable to derivation of the moments. Therefore, I rely on simulations, where data …


Sources Of Epidemiological Equivocacy, Timothy Sly Jan 1996

Sources Of Epidemiological Equivocacy, Timothy Sly

RISK: Health, Safety & Environment (1990-2002)

Mr. Sly discusses five sources of uncertainty and ambiguity in health and medical research that can interfere with decision making.


Environmental Racism And Biased Methods Of Risk Assessment, Daniel C. Wigley, Kristin S. Shrader-Frechette Jan 1996

Environmental Racism And Biased Methods Of Risk Assessment, Daniel C. Wigley, Kristin S. Shrader-Frechette

RISK: Health, Safety & Environment (1990-2002)

Based on analysis of a risk assessment for a proposed Louisiana uranium enrichment facility, the authors argue that environmental injustice occurs when assessors' scientific methods cause de facto discrimination.


Review Of: It Just Ain't Fair: The Ethics Of Health Care For African Americans (Annette Dula & Sara Goering Eds.), Carrie Anne Juliano Jan 1995

Review Of: It Just Ain't Fair: The Ethics Of Health Care For African Americans (Annette Dula & Sara Goering Eds.), Carrie Anne Juliano

RISK: Health, Safety & Environment (1990-2002)

Review of: It Just Ain't Fair: The Ethics of Health Care for African Americans (Annette Dula & Sara Goering eds., Praeger 1994) About the editors and contributors, acknowledgements, bibliography, foreword by Mark Siegler, index, notes. L.C. 93-43780, ISBN 0-275-94494-8. [ 336 pp. Paper $19.95. P.O. Box 5007, Westport CT 06881-5007.]