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ERIC Number: EJ827259
Record Type: Journal
Publication Date: 2009
Pages: 15
Abstractor: As Provided
ISSN: ISSN-0013-1644
Constraint-Weighted a-Stratification for Computerized Adaptive Testing with Nonstatistical Constraints: Balancing Measurement Efficiency and Exposure Control
Cheng, Ying; Chang, Hua-Hua; Douglas, Jeffrey; Guo, Fanmin
Educational and Psychological Measurement, v69 n1 p35-49 2009
a-stratification is a method that utilizes items with small discrimination (a) parameters early in an exam and those with higher a values when more is learned about the ability parameter. It can achieve much better item usage than the maximum information criterion (MIC). To make a-stratification more practical and more widely applicable, a method for weighting the item selection process in a-stratification as a means of satisfying multiple test constraints is proposed. This method is studied in simulation against an analogous method without stratification as well as a-stratification using descending-rather than ascending-a procedures. In addition, a variation of a-stratification that allows for unbalanced usage of a parameters is included in the study to examine the trade-off between efficiency and exposure control. Finally, MIC and randomized item selection are included as baseline measures. Results indicate that the weighting mechanism successfully addresses the constraints, that stratification helps to a great extent balancing exposure rates, and that the ascending-a design improves measurement precision. (Contains 4 tables and 1 figure.)
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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