Academic and non-academic licenses for IRT software products
- SSI, Inc. offers academic and non-academic (production and commercial) licenses for its IRT software products.
- Academic licenses apply to end users that intend to use the software exclusively for academic research and instruction.
- Non-academic licenses apply to end users that intend to use the software for assessment.
- Academic licenses for BILOG-MG, IRTPRO, and PARSCALE for Windows can be purchased by academic end users with legitimate academic email addresses via the SSI Shopping Cart.
- Single 12 month non-academic licenses for BILOG-MG, IRTPRO, and PARSCALE for Windows can be purchased via the SSI Shopping Cart.
IRTPRO 2.1 for Windows by Li Cai, David Thissen & Stephen du Toit
BILOG-MG 3 by Michele Zimowski, Eiji Muraki, Robert Mislevy & Darrell Bock
- Graphical user interface
- Efficient analysis of binary items including multiple choice or short-answer items scored right, wrong, omitted, or not-presented
- 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")
- Item fit statistics, theoretical and empirical reliability
- Information curves and reliabilities for putative test forms
- Presentation quality IRT graphics, can be imported in Word, Access, etc.
- Detailed online HELP documentation includes description of interface, syntax, and examples.
PARSCALE 4 by Eiji Muraki & Darrell Bock
- The flexibility and the wealth of information provided by this program have kept it in regular use by researchers around the world
- One, two, and three-parameter logistic models
- Samejima's model for graded responses
- Master's partial credit model
- Generalized partial credit model
- Analysis of rating scale items such as open-ended essay questions
- Analysis of multiple-choice items
- Differential item functioning (DIF)
- Analysis of mixtures of item types
- Rater's-effect analysis
- Multiple-group polytomous item response models
- Presentation quality IRT graphics, can be imported in Word, Access, etc.
- Detailed online HELP documentation includes syntax and examples.
- IRTPRO 3 for Windows is now available.
- The free trial edition of IRTPRO 3 for Windows is now available.
- The free student edition of IRTPRO 3 for Windows is now available.