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ERIC Number: EJ909161
Record Type: Journal
Publication Date: 2010-Dec
Pages: 12
Abstractor: As Provided
Reference Count: 19
ISSN: ISSN-0013-1644
Type I Error Inflation for Detecting DIF in the Presence of Impact
DeMars, Christine E.
Educational and Psychological Measurement, v70 n6 p961-972 Dec 2010
In this brief explication, two challenges for using differential item functioning (DIF) measures when there are large group differences in true proficiency are illustrated. Each of these difficulties may lead to inflated Type I error rates, for very different reasons. One problem is that groups matched on observed score are not necessarily well matched on true proficiency, which may result in the false detection of DIF due to inaccurate matching. The other problem is that a model that does not allow for a nonzero asymptote can produce what seems to be DIF. These issues have been discussed separately in the literature earlier. This article brings them together in a nontechnical form. (Contains 3 tables and 3 figures.)
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Publication Type: Journal Articles; Reports - Evaluative
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A