Announcing the Release of AUXAL 4

A new version of the AUXAL program is immediately available for purchase. Auxal4 uses the same empirical Bayes estimation procedure as AUXAL3, but has new features and improvements that extend the functionality of the program and make it easier to use.  The accuracy of the estimated population covariance matrix of the model parameters has been improved. Although archival of data from the Fels longitudinal study continues as the source of the default prior distribution means and covariance matrices for the … Read More

Announcing the Release of BILOG-MG 4

A new version of the BILOG-MG program is immediately available. New features Executables for running the Classical Statistics, Calibration and Scoring phases have been replaced with 32bit and 64bit dynamic link libraries. The GUI determines if the computer uses a 64bit or 32bit processor. The number of examinees in a dataset has been increased from 1 million to ten million. The maximum length of all file names has been changed from 128 to 256 characters. This “feature” is only useful … Read More

Announcing the release of SuperMix

A new version of the SuperMix program is immediately available. Use of Stat/Transfer Version 15 The data import feature has been upgraded from Stat/Transfer Version 14 to the most recently released Version 15 to ensure import/export compatibility with software packages such as SPSS, SAS and STATA. Among others, Stat/Transfer supports importing data from the most current SAS, SPSS, STATA, MINITAB, MATLAB and R software. Dynamic link libraries Executables have been replaced with 32bit and 64bit dynamic link libraries. The GUI … Read More

Announcing the release of PARSCALE 5

A new version of the PARSCALE program is immediately available. New features The number of examinees in a dataset has been increased from 1 million to ten million. The maximum length of all file names has been changed from 128 to 256 characters. This “feature” is only useful if the DLL can handle syntax file with directory. Currently the UI break the full path into <drive>/<dir> and <filename>, change the current working directory to <drive>/<dir> and call the BLM.exe with … Read More

More Programs Now Available on SSI Live™

SuperMix, BILOG-MG, PARSCALE, and AUXAL joins SSI Live™ as subscriptions. SSI is pleased to announce the immediate availability of new versions of SuperMix, BILOG-MG, PARSCALE, and AUXAL as software subscriptions on SSI Live™, our brand new licensing, delivery, and support system.  With your renewable SSI Live™ subscription, you are entitled to many more benefits in comparison to previous licensing models.  Four subscription tiers are available at varying lengths (from 3-month to 12-month): Operational, Commercial, Standard, and Basic. Click here to view a side-by-side comparison … Read More

VPG Releases New Version of IRTPRO

SSI’s parent company, Vector Psychometric Group, LLC, released IRTPRO 5. IRTPRO™ is an application for comprehensive item calibration and test scoring using IRT models. IRTPRO™ was first released in 2010.  The current version of IRTPRO™ is Version 5.0 (released date: June 17, 2020). As of June 17, 2020, IRTPRO™ is no longer marketed by SSI.  Instead, SSI’s parent company, Vector Psychometric Group, LLC, is exclusively marketing IRTPRO™ under a subscription-based software delivery and support model.  Please visit the updated online store … Read More

HLM 8 Now Available on SSI Live™

HLM transitions to the SSI Live™ software-as-subscription service. We are pleased to announce that after several years of development, SSI is offering a brand new HLM software licensing, delivery, and support model. We call it SSI Live™. HLM is the first program to transition to the new model. SSI Live™ is a subscription, similar to the popular rental licenses that we used to market, but with many more features.With your renewable SSI Live™ subscription, you are entitled to many more benefits in comparison to … Read More

SSI Acquired by Vector Psychometric Group

Scientific Software International Inc. is acquired by Vector Psychometric Group. We are happy to announce that in early 2020, Scientific Software International Inc., became a wholly owned subsidiary of Vector Psychometric Group, LLC, a North Carolina-based software and consulting company. We believe this exciting new development in SSI’s corporate history will reinvigorate the SSI products that have for so long formed the backbone of research in a variety of fields. An important part of this evolution of SSI is the gradual roll-out … Read More

Introducing New Features in HLM 8

The HLM8 program has a number of new statistical features. Estimating HLM from incomplete data In HLM 8, the ability to estimate an HLM from incomplete data was added. This is a completely automated approach that generates and analyses multiply imputed data sets from incomplete data. The model is fully multivariate and enables the analyst to strengthen imputation through auxiliary variables. This means that the user specifies the HLM; the program automatically searches the data to discover which variables have … Read More

Introducing New Features in LISREL 10

The LISREL10 program has a number of new statistical features. Structural equation modeling (SEM) was introduced initially as a way of analyzing a covariance or correlation matrix. Typically, one would read this matrix into LISREL and estimate the model by maximum likelihood. If raw data was available without missing values, one could also use PRELIS first to estimate an asymptotic covariance matrix to obtain robust estimates of standard errors and chi-squares. Modern structural equation modeling is based on raw data. … Read More