A state exchanging method for parallel test forms

Abstract

The construction of parallel test forms(i.e.,tests with similar difficulty) is a very important task in educational measurement. In the past two decades, a variety of methods based on the item response theory(IRT)have been proposed to construct parallel test forms. The previously proposed methods can efficiently select items to construct a test that approximates the test informatioin function of a target test. In this paper, we propose a more effective method based on the state exchange technique that can greatly reduce the error of the test information functions of parallel tests generated by other methods. Experimental results show that this method sharply reduces error with improvement ratios exveeding 96.9% In addition the computation complexity of our method is the same as that of other methods. This method should greatly aid in the construction of parallel test forms