Preparation of this paper was supported in part by a grant from the Spencer Founda- tion. I am grateful to David E. Wiley for his helpful discussions of both the methods developed in this paper and the logical foundations of the binary skills model. I thank Clifford C. Clogg for information about the application of latent class models to large numbers of items. I also thank Wendy M. Yen and anonymous reviewers for their helpful suggestions.
Using Restricted Latent Class Models to Map the Skill Structure of Achievement Items
Article first published online: 12 SEP 2005
Journal of Educational Measurement
Volume 26, Issue 4, pages 301–321, December 1989
How to Cite
Haertel, E. H. (1989), Using Restricted Latent Class Models to Map the Skill Structure of Achievement Items. Journal of Educational Measurement, 26: 301–321. doi: 10.1111/j.1745-3984.1989.tb00336.x
Copies of this paper may be requested from Edward H. Haertel, School of Education, Stanford University, Stanford, California 94305–3096
- Issue published online: 12 SEP 2005
- Article first published online: 12 SEP 2005
This paper presents a new method for using certain restricted latent class models, referred to as binary skills models, to determine the skills required by a set o f test items. The method is applied to reading achievement data from a nationally representative sample o f fourth-grade students and offers useful perspectives on test structure and examinee ability, distinct from those provided by other methods o f analysis. Models fitted to small, overlapping sets o f items are integrated into a common skill map, and the nature o f each skill is then inferred from the characteristics o f the items for which it is required. The reading comprehension items examined conform closely to a unidimensional scale with six discrete skill levels that range from an inability to comprehend or match isolated words in a reading passage to the abilities required to integrate passage content with general knowledge and to recognize the main ideas o f the most difficult passages on the test.