The present guide provides a practical guide to conducting latent profile analysis (LPA) in the Mplus software system. This guide is intended for researchers familiar with some latent variable modeling but not LPA specifically. A general procedure for conducting LPA is provided in six steps: (a) data inspection, (b) iterative evaluation of models,…

About 45 R packages to analyze data using item response theory (IRT) have been developed over the last decade. This article introduces these 45 R packages with their descriptions and features. It also describes possible advanced IRT models using R packages, as well as dichotomous and polytomous IRT models, and R packages that contain applications…

In order to progress as a field, school psychology research must be informed by effective measurement techniques. One approach to address the need for careful measurement is Rasch analysis. This technique can (a) facilitate the development of instruments that provide useful data, (b) provide data that can be used confidently for both descriptive…

This comprehensive "Handbook" focuses on the most used polytomous item response theory (IRT) models. These models help us understand the interaction between examinees and test questions where the questions have various response categories. The book reviews all of the major models and includes discussions about how and where the models…

This report documents a computer program for simulation evaluation of item response theory (IRT) ability estimators. This Honeywell DPS version is a very slight modification of the program originally developed in FORTRAN-77 on a DEC VAX 11/780. The model of the world simulated by the program involves a unidimensional test in which the probability…

Ways in which the Statistical Package for the Social Sciences (SPSS) can be used to perform some Rasch analyses are described in detail. It is shown how SPSS and a set of item calibrations can be used to estimate person abilities, standard errors of measurement, test characteristic curve, test information curve, classification consistency on a…

This study examined the effect of type of correlation matrix on the robustness of LISREL maximum likelihood and unweighted least squares structural parameter estimates for models with categorical manifest variables. Two types of correlation matrices were analyzed; one containing Pearson product-moment correlations and one containing tetrachoric,…

This paper discusses the use of the LISREL computer program to compare two groups of Ontario students who studied French as a second language in either a regular or an immersion program. Longitudinal data on growth in mathematical ability, from grade 4 to grade 6, are analyzed using seven different mathematical models. The paper illustrates the…