ERIC Number: ED422359
Record Type: RIE
Publication Date: 1998-Apr
Adaptive Testing without IRT.
Yan, Duanli; Lewis, Charles; Stocking, Martha
It is unrealistic to suppose that standard item response theory (IRT) models will be appropriate for all new and currently considered computer-based tests. In addition to developing new models, researchers will need to give some attention to the possibility of constructing and analyzing new tests without the aid of strong models. Computerized adaptive testing currently relies heavily on IRT. Alternative, empirically based, nonparametric adaptive testing algorithms exist, but their properties are little known. This paper introduces an adaptive testing algorithm that balances maximum differentiation among test takers with stable estimation at each stage of testing, and compares this algorithm with a traditional one using IRT and maximum information. The adaptive testing algorithm introduced is based on the classification and regression tree approach described in L. Breiman, J. Friedman, R. Olshen, and C. Stone (1984) and J. Chambers and T. Hastie (1992). Simulation results from the regression tree approach were compared with simulation results from three parameter logistic model IRT. Simulation results show that the nonparametric tree-based approach to adaptive testing may be superior to conventional IRT-based adaptive testing in cases where the IRT assumptions are not satisfied. It clearly outperformed one-dimensional IRT when the pool was strongly two-dimensional. A technical appendix describes the algorithm. (Contains three figures and six references.) (SLD)
Publication Type: Reports - Evaluative; Speeches/Meeting Papers
Education Level: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A
Note: Paper presented at the Annual Meeting of the National Council on Measurement in Education (San Diego, CA, April 12-16, 1998).