Leading the science of assessment.
Consulting
Vector Psychometric Group is an empirically-driven organization, dedicated to improving the science of psychometrics and behavioral data analysis for our clients, whether they are government agencies, medical device and pharmaceutical companies, sports teams, research organizations, or academic researchers.
Software
Vector Psychometric Group offers the most advanced psychometric software on the market, including the flexMIRT® and IRTPRO™ packages for item and test analysis and psychometric scoring, and the Adaptest® computerized adaptive testing (CAT) EDC/ePRO “plug-in”. We also offer advanced psychometric capabilities through customized software integration or assessment system development.
Assessments
Vector Psychometric Group offers assessment tools for operational use (e.g., clinical trials, health outcomes, player evaluations). This service is designed to provide both the authors and end-users of the scales and assessments seamless online data collection, support, and psychometric expertise to ensure accurate scoring.
HLMix™ Public Beta Available
Vector Psychometric Group, LLC is pleased to announce the immediate availability of a public beta version of the brand new, entirely cloud-based software HLMix™ on SSI Live™. HLMix™ is a cloud-based program for analyzing 2- or 3-level hierarchically structured data with a wide range of outcome variable distributions and link functions. The program features a point-and-click interface compatible with any common web browser. Output is provided in both HTML and text format. In addition to standard output expected from multilevel … Read More
Educational Videos Available on YouTube
Vector Psychometric Group and Scientific Software International have created a YouTube Channel that includes educational videos on Item Response Theory Modeling, Introductory Multilevel Modeling and Advanced Multilevel Modeling.
Announcing LISREL 12
Vector Psychometric Group and Scientific Software International are pleased to announce the immediate availability of LISREL12. Read more about the latest features and models available here or watch this video.
Announcing the Release of IRTPRO™ 6.0
VPG is pleased to announce the immediate availability of IRTPRO™ Version 6.0 which includes improved scaling functionality to support UHD display resolution, tabbed child windows and an output panel to display additional information and for Academic license holders the ability to open a .flexMIRT syntax file directly within IRTPRO™. You can learn more about the new features of IRTPRO™ 6.0 in this video and on this support page. Users holding active IRTPRO™ subscription licenses are encouraged to upgrade, by logging … Read More
VPG releases flexMIRT® Version 3.6.5
VPG is pleased to announce the immediate availability of flexMIRT® Version 3.6.5. Version 3.6.5 fixes multiple bugs and has improved output and syntax parse error reporting.
R. Darrell Bock
We are sad to relay news of the death of R. Darrell Bock. Darrell was a titan in the field – his work defined the shape and trajectory of modern psychometrics. We each had the pleasure of meeting Darrell at various points in our careers and he was as impressive in person as he was in his published work. All three of us – indeed this entire company – have been shaped by Darrell’s many contributions. We echo the closing … Read More
Celebrating 50 Years of Structural Equation Modeling with LISREL
Scientific Software Inc., a wholly-owned subsidiary of Vector Psychometric Group, LLC, has released LISREL 11 on 06/24/2021. The substantially upgraded new version marks the golden jubilee of a seminal development in the history of Structure Equation Modeling (SEM). A little over a half century ago Professor Karl Jöreskog published a monograph in the Educational Testing Service (ETS) Research Bulletin series, entitled A General Method for Estimating a Linear Structural Equation System. The technical development was supported by the availability of … Read More
Vector Psychometric Group has acquired Scientific Software International, Inc.
Vector Software Acquisition, a sole subsidiary of Vector Psychometric Group, acquired Scientific Software International, Inc. expanding Vector’s statistical software offerings. Vector Psychometric Group (VPG), a leading provider of psychometric and data analytic solutions for clinical outcomes, educational, and psychological assessment, has acquired Scientific Software International, Inc. (SSI), a market-leader in statistical software for social, behavioral, and biostatistical sciences. SSI has been developing, publishing, and distributing specialized statistical software products since 1971. SSI has been a driving force behind many widely … Read More
VPG Awarded FDA Grant to Develop Clinical Outcome Assessments for Migraine
As part of our Patient Focused Drug Development (PFDD) efforts, the U.S. Food and Drug Administration (FDA) developed a pilot grant program to support the development of publicly available core set(s) of Clinical Outcome Assessments (COAs) and their related endpoints for specific disease indications (RFA-FD-19-006). On September 11, 2019 the FDA made three awards under this grant program. These awards will provide avenues to advance the use of patient input as an important part of drug development that can foster innovation and … Read More