ERIC Number: ED435691
Record Type: Non-Journal
Publication Date: 1999
Reference Count: N/A
CUSUM-Based Person-Fit Statistics for Adaptive Testing. Research Report 99-05.
van Krimpen-Stoop, Edith M. L. A.; Meijer, Rob R.
Item scores that do not fit an assumed item response theory model may cause the latent trait value to be estimated inaccurately. Several person-fit statistics for detecting nonfitting score patterns for paper-and-pencil tests have been proposed. In the context of computerized adaptive tests (CAT), the use of person-fit analysis has hardly been explored. In this study, new person-fit statistics are proposed, and critical values for these statistics are derived from existing statistical theory. Statistics are proposed that are sensitive to runs of correct or incorrect item scores and are based on all items administered in a CAT or based on subsets of items, using observed and expected item scores and using cumulative sum (CUSUM) procedures. The theoretical and empirical distributions of the statistics are compared and detection rates are investigated. Results show that the nominal and empirical Type I error rates are comparable for CUSUM procedures when the number of items in each subset and the number of measurement points are not too small. Detection rates of CUSUM procedures were superior to other fit statistics. Applications of the statistics are discussed. (Contains 5 tables and 21 references.) (Author/SLD)
Descriptors: Adaptive Testing, Computer Assisted Testing, Estimation (Mathematics), Item Response Theory
Faculty of Educational Science and Technology, University of Twente, TO/OMD, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Publication Type: Reports - Evaluative
Education Level: N/A
Sponsor: Law School Admissions Council, Newtown, PA.
Authoring Institution: Twente Univ., Enschede (Netherlands). Faculty of Educational Science and Technology.