DFIT

A set of functions to perform Raju, van der Linden and Fleer's (1995, doi:10.1177/014662169501900405) Differential Functioning of Items and Tests (DFIT) analyses. It includes functions to use the Monte Carlo Item Parameter Replication approach (Oshima, Raju, & Nanda, 2006, doi:10.1111/j.1745-3984.2006.00001.x) for obtaining the associated statistical significance tests cut-off points. They may also be used for a priori and post-hoc power calculations (Cervantes, 2017, doi:10.18637/jss.v076.i05).