An Investigation of Group Invariance in Test Equating According to Gender

The aim of this study is to investigate the group invariance condition according to Tucker and Levine observed score equating among linear equating methods. In the study, the 4 th and 6 th booklets of the PISA 2012 Mathematics subtest were used. Booklets were equated according to group and gender sub-variables, and then group invariance of each condition and WMSE values were calculated. Within this scope, REMSD and RMSD (x) group invariance indexes were employed. The results of the study indicated that, when WMSE values, obtained according to equating methods, were compared, Tucker observed score equating method with regard to whole-group and gender sub-groups produced the lowest error. When RMSD and REMSD values obtained according to gender sub-groups were examined by linear equating methods, it was found that group invariance value is smaller than criterion value for Tucker equating method, while it was greater than criterion value for Levine equating method. Eventually, group invariance condition was met for Tucker observed score equating, but not for Levine observed score equating .