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ERIC Number: EJ1141253
Record Type: Journal
Publication Date: 2017-Jun
Pages: 14
Abstractor: As Provided
ISSN: ISSN-0013-1644
Effect of Purification Procedures on DIF Analysis in IRTPRO
Fikis, David R. J.; Oshima, T. C.
Educational and Psychological Measurement, v77 n3 p415-428 Jun 2017
Purification of the test has been a well-accepted procedure in enhancing the performance of tests for differential item functioning (DIF). As defined by Lord, purification requires reestimation of ability parameters after removing DIF items before conducting the final DIF analysis. IRTPRO 3 is a recently updated program for analyses in item response theory, with built-in DIF tests but not purification procedures. A simulation study was conducted to investigate the effect of two new methods of purification. The results suggested that one of the purification procedures showed significantly improved power and Type I error. The procedure, which can be cumbersome by hand, can be easily applied by practitioners by using the web-based program developed for this study.
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A