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ERIC Number: EJ762143
Record Type: Journal
Publication Date: 2007
Pages: 24
Abstractor: Author
Reference Count: 55
ISSN: ISSN-0022-0655
DIF Detection and Effect Size Measures for Polytomously Scored Items
Kim, Seock-Ho; Cohen, Allan S.; Alagoz, Cigdem; Kim, Sukwoo
Journal of Educational Measurement, v44 n2 p93-116 Sum 2007
Data from a large-scale performance assessment (N = 105,731) were analyzed with five differential item functioning (DIF) detection methods for polytomous items to examine the congruence among the DIF detection methods. Two different versions of the item response theory (IRT) model-based likelihood ratio test, the logistic regression likelihood ratio test, the Mantel test, and the generalized Mantel-Haenszel test were compared. Results indicated some agreement among the five DIF detection methods. Because statistical power is a function of the sample size, the DIF detection results from extremely large data sets are not practically useful. As alternatives to the DIF detection methods, four IRT model-based indices of standardized impact and four observed-score indices of standardized impact for polytomous items were obtained and compared with the R[superscript 2] measures of logistic regression.
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Publication Type: Information Analyses; Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A