Announcing the Release of HLM 8.1

SSI is pleased to announce the immediate availability of HLM 8.1. The update contains substantial improvements and bug fixes over and above HLM 8.0, which was released in 2019. Users are encouraged to update their installations. Users with active SSI Live™ HLM subscription licenses can obtain this update free of charge by logging into My Account.

List of updates:


  • Improvements and corrections to model specification in GUI for multiple outcome models, HLM4 etc.
  • Corrected problems with the Exploratory Statistics options in HLM2 and 3.

Output files:

  • Problems with mixed model formulation in output file corrected for a number of cases, for example HLM4 and multiple outcome models.
  • Confidence intervals for taus refined.
  • Problems regarding production of and correct writing to residual files fixed.


  • Problems with degrees of freedom in HLM4 models has been fixed.
  • Revision of the weights implementation has been undertaken: only marginal weighting now implemented.
  • Graphing related crashes for categorical outcomes have been fixed.
  • Diagonalization of matrices revised.
  • Missing data issues in HLM3, HLM4, HCM2, HCM3 and HLMHCM addressed.
  • Additional information added to output files for the AI routine in the case of improper imputation.


Updated installers are now available for BILOG-MG 4, HLM 8.0 and LISREL 10.3.

The updated installers mask the license keys on output and provide a reminder around expiration dates. A few minor bugs have also been fixed.

Users holding active BILOG-MG 4, HLM 8.0 and LISREL 10.3 subscription licenses are encouraged to download the latest installers from their accounts on