Assessing the measurement model (MM) of self-report scales is crucial to obtain valid measurements of individuals' latent psychological constructs. This entails evaluating the number of measured constructs and determining which construct is measured by which item. Exploratory factor analysis (EFA) is the most-used method to evaluate these…

The present study presents the formulation of graded response models in the multilevel framework (as nonlinear mixed models) and demonstrates their use in estimating item parameters and investigating the group-level effects for specific covariates using Bayesian estimation. The graded response multilevel model (GRMM) combines the formulation of…

MetaDOS is a point-and-click PASCAL program for meta-analysis that provides a user-friendly, Windows-type interface for DOS systems. Its statistical procedures basically follow those developed by J. E. Hunter and F. L. Schmidt and their colleagues (1990 and 1993). (Author/SLD)

A FORTRAN 77 computer program is presented to perform analyses of differential item performance in psychometric tests. The program performs the Mantel-Haenszel procedure and computes additional classical indices of differential item functioning (DIF) and associated effect size measures. (Author/SLD)

Type I error rates for PARSCALE's fit statistic were examined. Data were generated to fit the partial credit or graded response model, with test lengths of 10 or 20 items. The ability distribution was simulated to be either normal or uniform. Type I error rates were inflated for the shorter test length and, for the graded-response model, also for…