GMHDIF: A Computer Program for Detecting DIF in Dichotomous and Polytomous Items Using Generalized Mantel-Haenszel Statistics

摘要

Mantel-Haenszel (MH) methods constitute one of the most popular nonparametric differential item functioning (DIF) detection procedures. To date, the statistical software designed for assessing DIF with MH procedures has used the MH chi-square statistic, (chi)_(MH)~(2) (Mantel & Haenszel, 1959), the generalized MH test (GMH; Mantel & Haenszel, 1959), and the Mantel test (Mantel, 1963). These statistics limit the DIF analysis to two groups. However, as described in Fidalgo and Madeira (2008), we can apply the generalized MH statistic proposed by Landis, Heyman, and Koch (1978) to DIF assessment in multiple groups, both for dichotomous items and polytomous items (Fidalgo & Scalon, 2010; Fidalgo, Quintanilla, Fernandez, Pons, & Aguerri, 2010). As is pointed out there, this statistic subsumes the (chi)_(MH)~(2) statistic, the GHM test, and the Mantel test.