SSI publishes and distributes specialized statistical software products that are useful for work in a variety of fields such as:

  • Statistics (including survey research and informatics)
  • Behavioral and social sciences (such as psychology, sociology, psychiatry, criminal science, family studies, political science, developmental research, anthropology, or social work)
  • Medical research (including nursing, pharmacy, epidemiology, gerontology, kinesiology, sport science, and other fields)
  • Education (in administration, policy studies, test analysis, counseling, and more)
  • Business research (marketing, management, economics, organization)
  • Environmental science (including resource administration and longitudinal research)
  • Other diverse research areas, such as language studies, engineering, law, chemistry, or urban planning


SSI Software

LISREL 10 provides tools for structural equation modeling, data manipulations and basic statistical analyses, hierarchical and non-linear modeling, generalized linear modeling, and generalized linear modeling for multilevel data.

HLM 8 
HLM provides statistical tools for comprehensive hierarchical data modeling.

IRTPRO (Item Response Theory for Patient-Reported Outcomes) is an application for comprehensive item calibration and test scoring using IRT models.

BILOG-MG is an extension of BILOG that is designed for the efficient analysis of binary items, including multiple-choice or short-answer items scored right, wrong, omitted, or not-presented.

PARSCALE implements Item Response Theory (IRT) measurement methods for binary, multiple-category and rating-scale items.

SuperMix 2 
SuperMix is an application for comprehensive mixed-effect modeling.