Estimating the Standard Error of the Maximum Likelihood Ability Estimator in Adaptive Testing Using the Posterior-Weighted Test Information Function

University of Miami

^* To whom correspondence should be addressed. E-mail: penfield{at}miami.edu.

	Abstract

The standard error of the maximum likelihood ability estimator is commonly estimated by evaluating the test information function at an examinee’s current maximum likelihood estimate (a point estimate) of ability. Because the test information function evaluated at the point estimate may differ from the test information function evaluated at an examinee’s true ability value, the estimated standard error may be biased under certain conditions. This is of particular concern in adaptive testing because the height of the test information function is expected to be higher at the current estimate of ability than at the actual value of ability. This article proposes using the posterior-weighted test information function in computing the standard error of the maximum likelihood ability estimator for adaptive test sessions. A simulation study showed that the proposed approach provides standard error estimates that are less biased and more efficient than those provided by the traditional point estimate approach.

First published on June 6, 2007, doi:10.1177/0013164407301544

Educational and Psychological Measurement 2007;67:958.

A more recent version of this article appeared on December 1, 2007


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				Ying Cheng, H.-H. Chang, J. Douglas, and Fanmin Guo Constraint-Weighted a-Stratification for Computerized Adaptive Testing With Nonstatistical Constraints: Balancing Measurement Efficiency and Exposure Control Educational and Psychological Measurement, February 1, 2009; 69(1): 35 - 49. [Abstract] [PDF]