A New Equating Criterion in Item Response Theory——COSine Criterion
Dengwen Gan · Journal of Jiangxi Normal University · 2008
The probability mass vectors of an examinee who responses to the ancher items in two test forms are intuitively quite approximate. Based on this intuition, a new test equating criterion, known as COSine criterion(COScrit), is proposed in this paper. The COScrit is compared with Haebara equating criterion(Hcrit)and Stocking-Lord equating criterion(SLcrit)through Monte Carlo simulation using Generalized Partial Credit Model. The study shows that the results of the new approach sometimes are better than Hcrit and SLcrit in terms of the recovery of estimating the equating coefficients and have significant differences when the value of the equating coefficient A is about 0.9 to 2.0.