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ERIC Number: EJ819616
Record Type: Journal
Publication Date: 2008
Pages: 27
Abstractor: As Provided
Reference Count: 50
ISSN: ISSN-0022-0655
Summarizing Item Difficulty Variation with Parcel Scores
Camilli, Gregory; Prowker, Adam; Dossey, John A.; Lindquist, Mary M.; Chiu, Ting-Wei; Vargas, Sadako; de la Torre, Jimmy
Journal of Educational Measurement, v45 n4 p363-389 Win 2008
A new method for analyzing differential item functioning is proposed to investigate the relative strengths and weaknesses of multiple groups of examinees. Accordingly, the notion of a conditional measure of difference between two groups (Reference and Focal) is generalized to a conditional variance. The objective of this article is to present and illustrate a strategy for aggregating results across sets of similar items that exhibit item difficulty variation. Logically, this aggregation strategy is related to the idea of DIF amplification, but estimation is ultimately carried out in the framework of a confirmatory multidimensional Rasch model. Grade 4 data from the 2000 National Assessment of Educational Progress are used to illustrate the technique. (Contains 1 figure, 6 tables, and 22 formulas.)
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: Grade 4
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A