For a test that consists of dichotomously scored items, several approaches have been reported in the literature for estimating classification consistency and accuracy indices based on a single administration of a test. Classification consistency and accuracy have not been studied much, however, for "complex" assessments--for example,…

A multidimensional item response theory model that accounts for response style factors is presented. The model, a multidimensional extension of Bock's nominal response model, is shown to allow for the study and control of response style effects in ordered rating scale data so as to reduce bias in measurement of the intended trait. In the current…

Suggests that modeling change on the latent dimensions of interest is a better approach to measuring change than focusing on observed change scores and their properties. Discusses a latent-variable modeling approach that focuses on ability-change scores to permit estimation of individual latent-change scores and the relationship of ability-change…

Rasch's psychometric model is presented as a special case of additive conjoint measurement. Two data sets, each of which was analyzed using Rasch scaling methods as well as some of the methods of conjoint measurement, are compared. (Author/JKS)

The GGUM2004 computer program estimates parameters for a family of unidimensional unfolding item response theory (IRT) models. These unfolding IRT models predict higher item scores to the extent that a respondent is located close to an item on an underlying latent continuum. This prediction is often consistent with responses to traditional…

An item response model is proposed for the analysis of continuous response formats in an item response theory (IRT) framework. With such formats, respondents are asked to report their response as a mark on a fixed-length graphical segment whose ends are labeled with extreme responses. An interpolation process is proposed as the response mechanism…