Corporate History

Scientific Software International Inc. was incorporated in the State of Michigan in December 1971 and commenced business in April 1972.  SSI’s intellectual roots go back to Professor R. Darrell Bock (SSI’s co-founder and long-time President), prominent academic statistician, professor of Psychology at University of Chicago, and author of numerous statistical software programs of foundational importance to educational and psychological research.

From the mainframe era, to Unix workstations, to personal computers, and now to the cloud-based software-as-a-service model, SSI has led the market in offering the most sophisticated software solutions using cutting-edge methodological approaches to support and enable researchers across a wide variety of fields for the advancement of scientific knowledge and tools.

In early 2020, Vector Psychometric Group, LLC, a North Carolina based software and consulting company, acquired SSI as its wholly owned subsidiary. Vector Psychometric Group (VPG) is a leading provider of psychometric and data analytic solutions for clinical outcomes, educational, and psychological assessment. Jointly VPG and SSI provide nearly 60 years of statistical software development experience. This combined experience has allowed the companies to expand their current software capabilities, rejuvenate existing products, and build on their long history of advancing the statistical, psychometric, and data sciences through software.