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
VPG is pleased to announce the immediate availability of IRTPRO™ Version 5.1 which includes bug fixes and a new ICC/TIF plot display control option in both the Advanced Options dialog and command line syntax. Users holding active IRTPRO™ subscription licenses are encouraged to upgrade, by logging into their account on the VPG Store and navigating to the License Detail record under My Account – Licenses – Manage.
VPG is pleased to announce the immediately availability of flexMIRT® Version 3.62. Version 3.62 fixes a bug with multiple-group IRT modeling, and a labeling issue in output delivery. Importantly, Version 3.62 uses a completely new pseudo random number generator (PRNG), replacing the one that has been in use since flexMIRT 2.0. The new proprietary PRNG is based on the popular Mersenne Twister 19937 generator that substantially outperforms the PRNG used by flexMIRT previously. They will lead to slightly different results … Read More
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
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