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ERIC Number: EJ1067646
Record Type: Journal
Publication Date: 2015-Aug
Pages: 29
Abstractor: As Provided
ISSN: ISSN-0013-1644
Differential Item Functioning Detection across Two Methods of Defining Group Comparisons: Pairwise and Composite Group Comparisons
Sari, Halil Ibrahim; Huggins, Anne Corinne
Educational and Psychological Measurement, v75 n4 p648-676 Aug 2015
This study compares two methods of defining groups for the detection of differential item functioning (DIF): (a) pairwise comparisons and (b) composite group comparisons. We aim to emphasize and empirically support the notion that the choice of pairwise versus composite group definitions in DIF is a reflection of how one defines fairness in DIF studies. In this study, a simulation was conducted based on data from a 60-item ACT Mathematics test (ACT; Hanson & Béguin). The unsigned area measure method (Raju) was used as the DIF detection method. An application to operational data was also completed in the study, as well as a comparison of observed Type I error rates and false discovery rates across the two methods of defining groups. Results indicate that the amount of flagged DIF or interpretations about DIF in all conditions were not the same across the two methods, and there may be some benefits to using composite group approaches. The results are discussed in connection to differing definitions of fairness. Recommendations for practice are made.
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Publication Type: Journal Articles; Reports - Research
Education Level: Higher Education; Postsecondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Identifiers - Assessments and Surveys: ACT Assessment
Grant or Contract Numbers: N/A