ERIC Number: ED380499
Record Type: Non-Journal
Publication Date: 1994-Oct
Reference Count: N/A
Equity Assessment for Polytomously Scored Items: A Taxonomy of Procedures for Assessing Differential Item Functioning. Research Report RR-94-49.
Dorans, Neil J.; Potenza, Maria T.
Educational reform efforts have led to increased use of alternatives to the traditional binary-scored multiple choice item. Many stimuli employed by these alternative assessments yield complex responses that require complex scoring rules. Some of these new item types can be polytomously-scored. Differential item functioning (DIF) assessment is a form of equity assessment that attempts to identify items for which subpopulations of examinees exhibit performance differentials that are inconsistent with the performance differentials typically seen for those subpopulations on collections of items that purport to measure a common construct. Any DIF technique should be evaluated in terms of how well it meets certain statistical and practical criteria before it can be concluded that the items associated with alternative forms of assessment can be adequately tested for DIF. DIF methodology is well-defined for traditional, binary-scored multiple-choice items. This paper provides a classification scheme of DIF procedures for binary-scored items that is applicable to new DIF procedures for polytomously scored items. In the process, a formal development of a polytomous version of a binary DIF technique is presented. Finally, several polytomous DIF techniques are evaluated in terms of statistical and practical criteria. (Contains 65 references and 3 tables). (Author/SLD)
Publication Type: Reports - Evaluative; Speeches/Meeting Papers
Education Level: N/A
Authoring Institution: Educational Testing Service, Princeton, NJ.