Guilford's structure of intellect model and an alternative model were compared using oblique and orthogonal factors. Using covariance structure analysis it was found that the fit of the oblique Guilford model was better than that of the alternative oblique model. (Author/RL)

Describes algorithms used in the computer program LOGIMO for obtaining maximum likelihood estimates of the parameters in loglinear models. These algorithms are also useful for the analysis of loglinear item-response theory models. Presents modified versions of the iterative proportional fitting and Newton-Raphson algorithms. Simulated data…

In the last decade, several attempts have been made to relate item response theory (IRT) models to latent class analysis (LCA) models. One of these attempts is the solution-error response-error (SERS) model, an LCA model in which the structure of the latent class probabilities is explained by a one-dimensional loglinear Rasch model. In this paper,…

Loglinear latent class models are used to detect differential item functioning (DIF). Likelihood ratio tests for assessing the presence of various types of DIF are described, and these methods are illustrated through the analysis of a "real world" data set. (TJH)

A method is proposed for equating different sets of items administered to different groups using the Rasch model. The Rasch equating model formulated describes one common Rasch scale in different groups with different but overlapping item sets. The model, based on the quasi-loglinear Rasch model, can be tested globally. (SLD)

The Rasch Model and various extensions of this model can be formulated as a quasi loglinear model for the incomplete subgroup x score x item response 1 x ... x item response k contingency table. By comparing various loglinear models, specific deviations of the Rasch model can be tested. Parameter estimates can be computed using programs such as…

A method is proposed for the detection of item bias with respect to observed or unobserved subgroups, using a loglinear item response theory model assuming a Rasch model for ability and difficulty. A simulation study was performed with 200 sets of data to check the robustness of the method. (SLD)

In this paper, algorithms are described for obtaining the maximum likelihood estimates of the parameters in log-linear models. Modified versions of the iterative proportional fitting and Newton-Raphson algorithms are described that work on the minimal sufficient statistics rather than on the usual counts in the full contingency table. This is…

A method is proposed for the detection of item bias with respect to observed or unobserved subgroups. The method uses quasi-loglinear models for the incomplete subgroup x test score x item 1 x ... x item k contingency table. If the subgroup membership is unknown, the models are the incomplete-latent-class models of S. J. Haberman (1979). The…

The use of loglinear latent class models to detect item bias was studied. Purposes of the study were to: (1) develop procedures for use in assessing item bias when the grouping variable with respect to which bias occurs is not observed; (2) develop bias detection procedures that relate to a conceptually different assessed trait--a categorical…

In multiple-choice items the response probability on an item may be viewed as the result of two distinct latent processes--a cognitive process to solve the problem, and another random process that leads to the choice of a certain alternative (the process of giving the actual response). An incomplete latent class model is formulated that describes…

A method is proposed to equate different sets of items administered to different groups of individuals using the Rasch model. A Rasch equating model was formulated to describe one common Rasch scale in different groups with different but overlapping sets of items. The item parameters can then be estimated simultaneously, avoiding different…

A method for analyzing test-item responses is proposed to examine differential item functioning (DIF) in multiple-choice items within the latent class framework. Different models for detection of DIF are formulated, defining the subgroup as a latent variable. An efficient estimation method is described and illustrated. (SLD)

A loglinear item response theory (IRT) model is proposed that relates polytomously scored item responses to a multidimensional latent space. Each item may have a different response function where each item response may be explained by one or more latent traits. Item response functions may follow a partial credit model (D. Andrich, 1978; and G. N.…