Applying Differential Item Functioning to Validate the Construct Structure and Diagnostic Classification for Diagnostic Assessment

• In Event: Poster Session 10
  In Poster Session: Cognition and Assessment SIG Poster Session

Abstract

The present study aimed to apply DIF to validate the hypothesized construct structure (Q-matrix) of the mathematics items and the classification results from the DINA model. Dogan (2008) argued that if the focal and reference subgroups are formed based on the Q-matrix and the classification results from a cognitive diagnosis model, the degree of DIF an item displays can give us a clue about the validity of the hypothesized construct structure and the diagnostic classification results. The mathematics achievement data and test items derived from the TIMSS-2007 were used. Cognitive skills and the Q-matrix for the TIMSS-2007 mathematics items were adopted from Lee, Park, and Taylan (2011). It is hoped that every individual item shows DIF in this study.

Author

• Yi-Hsin Chen, University of South Florida