ERIC Number: ED344940
Record Type: RIE
Publication Date: 1992-Apr
Reference Count: 0
A Comparison of Unidimensional and Multidimensional IRT Approaches to Test Information in a Test Battery.
Chang, Yu-Wen; Davison, Mark L.
Standard errors and bias of unidimensional and multidimensional ability estimates were compared in a factorial, simulation design with two item response theory (IRT) approaches, two levels of test correlation (0.42 and 0.63), two sample sizes (500 and 1,000), and a hierarchical test content structure. Bias and standard errors of subtest scores (subtests within longer tests) were smaller for the multidimensional approach, but the bias of longer test scores did not improve. Sample size and test intercorrelation had a negligible effect on the results. As the number of items in a test becomes large, in an absolute sense, and relative to the total number in the battery, the advantage of the multidimensional approach seems to disappear. Two tables and 13 figures present results of the simulation. There is an 11-item list of references. (SLD)
Publication Type: Reports - Evaluative; Speeches/Meeting Papers
Education Level: N/A
Authoring Institution: N/A
Identifiers: Ability Estimates; Multidimensional Models; Test Batteries; Unidimensional Models
Note: Paper presented at the Annual Meeting of the American Educational Research Association (San Francisco, CA, April 20-24, 1992).