BILOG-MG is a script-based program that features a graphical system.
BILOG-MG is a script-based program that features a graphical system to help set up the script files.
Features:
-Capable of large scale production analysis, and handling of multiple groups
-Performs item analysis and scoring of any number of subtests or subscales
-Non-equivalent groups equating
-Vertical equating of test forms
-Differential item functioning (DIF)
-Detection and correction for parameter trends over time (DRIFT)
-Calibration and Scoring of tests in two-stage testing procedures
-Estimation of latent ability or proficiency distributions
-Provision for items inserted in tests to estimate item statistics, but not included in calculation of examinee scores ("variant items")