This work was completed while the author was at the Law School Admission Council.
The Effect of Multidimensionality on IRT True-Score Equating for Subgroups of Examinees
Version of Record online: 12 SEP 2005
Journal of Educational Measurement
Volume 33, Issue 2, pages 181–201, June 1996
How to Cite
De Champlain, A. F. (1996), The Effect of Multidimensionality on IRT True-Score Equating for Subgroups of Examinees. Journal of Educational Measurement, 33: 181–201. doi: 10.1111/j.1745-3984.1996.tb00488.x
The author would like to thank Peter Pashley, Maurice Tatsuoka, and Linda Wightman for their helpful suggestions and Lisa Anthony for her assistance. The author also wishes to thank the editor and two anonymous reviewers for their helpful comments on an earlier draft. This research was presented at the Annual Meeting of the National Council on Measurement in Education, San Francisco, CA, April, 1995.
- Issue online: 12 SEP 2005
- Version of Record online: 12 SEP 2005
The purpose of this study was to assess the dimensionality of two forms of a large-scale standardized test separately for 3 ethnic groups of examinees and to investigate whether differences in their latent trait composites have any impact on unidimensional item response theory true-score equating functions. Specifically, separate equating functions for African American and Hispanic examinees were compared to those of a Caucasian group as well as the total test taker population. On both forms, a 2-dimensional model adequately accounted for the item responses of Caucasian and African American examinees, whereas a more complex model was required for the Hispanic subgroup. The differences between equating functions for the 3 ethnic groups and the total test taker population were small and tended to be located at the low end of the score scale.