Getting Started with IRT programs

• Fitting a 1-parameter model to frequency data

Here, the same example is set up in three programs. Differences between the programs and a comparision of syntax/keywords are provided.

BILOG MG

• Analysis of variant items

MULTILOG

• Generating the syntax file
• Scoring individuals

PARSCALE

• DIF Analysis Using a Partial Credit Model
• Calibration and EAP Scoring with a Graded Model
• MLE Scoring with a Graded Model
• EAP Scores with Generalized Partial Credit Model
  

TESTFACT

• Non-adaptive full information item factor analysis
• Adaptive item factor analysis and factor score (EAP) estimation
• Adaptive item factor analysis and factor score (MAP) estimation
• Six-factor analysis by MCEM full-information analysis
• Item bifactor analysis of a twelfth-grade science assessment test