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ERIC Number: EJ1111376
Record Type: Journal
Publication Date: 2005-Dec
Pages: 29
Abstractor: As Provided
ISSN: EISSN-2330-8516
A Didactic Approach to the Use of IRT True-Score Equating. Research Report. ETS RR-05-26
von Davier, Alina A.; Wilson, Christine
ETS Research Report Series, Dec 2005
This paper discusses the assumptions required by the item response theory (IRT) true-score equating method (with Stocking & Lord, 1983; scaling approach), which is commonly used in the nonequivalent groups with an anchor data-collection design. More precisely, this paper investigates the assumptions made at each step by the IRT approach to calibrating items and equating tests, and discusses the approaches that one might take for checking whether these assumptions are met for a particular data set. We investigated two types of tests: tests that consist of multiple-choice items only, and tests that consist of both multiple-choice and free-response items. Real data from the AP® Calculus AB exam are used to illustrate the application of the IRT true-score equating method as well as for the comparisons.
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Identifiers - Assessments and Surveys: Advanced Placement Examinations (CEEB)
Grant or Contract Numbers: N/A