Article contents
A Relation Between a Between-Item Multidimensional IRT Model and the Mixture Rasch Model
Published online by Cambridge University Press: 01 January 2025
Abstract
Two generalizations of the Rasch model are compared: the between-item multidimensional model (Adams, Wilson, and Wang, 1997), and the mixture Rasch model (Mislevy & Verhelst, 1990; Rost, 1990). It is shown that the between-item multidimensional model is formally equivalent with a continuous mixture of Rasch models for which, within each class of the mixture, the item parameters are equal to the item parameters of the multidimensional model up to a shift parameter that is specific for the dimension an item belongs to in the multidimensional model. In a simulation study, the relation between both types of models also holds when the number of classes of the mixture is as small as two. The relation is illustrated with a study on verbal aggression.
- Type
- Original Paper
- Information
- Copyright
- Copyright © 2005 The Psychometric Society
Footnotes
Frank Rijmen was supported by the Fund for Scientific Research Flanders (FWO). This research is also funded by the GOA/2000/02 granted from the KU Leuven.
We would like to thank Kristof Vansteelandt for providing the data of the study on verbal aggression.
References
- 10
- Cited by