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
Announcing the Release of IRTPRO™ 5.2
VPG is pleased to announce the immediate availability of IRTPRO™ Version 5.2 which includes an option to import current Excel spreadsheets (*.xlsx) in addition to older Excel spreadsheets (*.xls extension). 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 releases flexMIRT® Version 3.6.4
VPG is pleased to announce the immediately availability of flexMIRT® Version 3.6.4. Version 3.6.4 fixes multiple bugs. Users holding active flexMIRT® subscription licenses are encouraged to upgrade.
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
Announcing the release of IRTPRO™ 5.1
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.