NotesFAQContact Us
Search Tips
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ1171105
Record Type: Journal
Publication Date: 2018
Pages: 20
Abstractor: As Provided
ISSN: ISSN-0022-0655
Aggregating Polytomous DIF Results over Multiple Test Administrations
Zwick, Rebecca; Ye, Lei; Isham, Steven
Journal of Educational Measurement, v55 n1 p132-151 Spr 2018
In typical differential item functioning (DIF) assessments, an item's DIF status is not influenced by its status in previous test administrations. An item that has shown DIF at multiple administrations may be treated the same way as an item that has shown DIF in only the most recent administration. Therefore, much useful information about the item's functioning is ignored. In earlier work, we developed the Bayesian updating (BU) DIF procedure for dichotomous items and showed how it could be used to formally aggregate DIF results over administrations. More recently, we extended the BU method to the case of polytomously scored items. We conducted an extensive simulation study that included four "administrations" of a test. For the single-administration case, we compared the Bayesian approach to an existing polytomous-DIF procedure. For the multiple-administration case, we compared BU to two non-Bayesian methods of aggregating the polytomous-DIF results over administrations. We concluded that both the BU approach and a simple non-Bayesian method show promise as methods of aggregating polytomous DIF results over administrations.
Wiley-Blackwell. 350 Main Street, Malden, MA 02148. Tel: 800-835-6770; Tel: 781-388-8598; Fax: 781-388-8232; e-mail:; Web site:
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