A Comparison of Item Response Theory And Observed Score DIF Detection Measures For the Graded Response Model

This paper provides a review of procedures for detection of differential item functioning (DIF) for item response theory (IRT) and observed score methods for the graded response model. In addition, data from a test anxiety scale were analyzed to examine the congruence among these procedures. Data from Nasser, Takahashi, and Benson (1997) were reanalyzed for purposes of this study. The data were obtained from participants' responses to an Arabic Version of Sarason's (1984) Reactions to Test (RTT) scale. The sample consisted of 421 tenth graders from two Arab high schools in the central district of Israel. Results indicated stronger agreement within IRT methods and within observed score methods than between these two sets of DIF detection methods. A discussion is included focusing on reasons for these similarities and differences. Results of this study can provide useful information about the relationships to expect between various DIF detection methods. (Contains 10 tables and 49 references.) (Author/SLD) ******************************************************************************** Reproductions supplied by EDRS are the best that can be made from the original document. ******************************************************************************** A Comparison of Item Response Theory And Observed Score DIF Detection Measures For the Graded Response Model Allan S. Cohen University of WisconsinMadison Seock-Ho Kim The University of Georgia James A. Wollack University of WisconsinMadison , April 14, 1998 Running Head: COMPARISON OF DIF DETECTION Paper presented at the annual meeting of the National Council on Measurement in Education, San Diego, California PERMISSION TO REPRODUCE AND DISSEMINATE THIS MATERIAL HAS BEEN GRANTED BY SQ-40e-KAo Kcon TO THE EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) 2 U.S. DEPARTMENT OF EDUCATION Office of Educational Research and Improvement EDU ATIONAL RESOURCES INFORMATION CENTER (ERIC) This document has been reproduced as received from the person or organization originating it. Minor changes have been made to improve reproduction quality. Points of view or opinions stated in this document do not necessarily represent official OERI position or policy. A Comparison of Item Response Theory And Observed Score DIF Detection Measures For the Graded Response Model