Rasch Model Calibrations with SAS PROC IRT and WINSTEPS.

The WINSTEPS software is widely used for Rasch model calibrations. Recently, SAS/STAT released the PROC IRT procedure for IRT analysis, including Rasch. The purpose of the study is compare the performance of the PROC IRT procedure with WINSTEPS to calibrate dichotomous and polytomous Rasch models in order to diagnose the possibility of using PROC IRT as a viable alternative. A simulation study was used to compare the two programs in terms of the convergence rate, run time, item parameter estimates, and ability estimates with different test lengths and sample sizes. Implications of the results and the features of each software are discussed for research applications and large-scale assessment.