[A new method for estimating differential item functioning (DIF) for multiple groups and polytomous items:

Ryuichi Kumagai1

  • 1Graduate School of Education, Tohoku University, Kawauchi, Aoba-ku, Sendai 980-8576, Japan. ryuichi@sed.tohoku.ac.jp

Summary

We introduce index K, a new method for estimating differential item functioning (DIF) across multiple groups. The EasyDIF program simplifies DIF analysis for polytomous items and offers graphical output, performing comparably to existing methods.

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