Mplus is a comprehensive, syntax-based statistical modeling software program designed to help researchers analyze complex data. It is widely used across the social, behavioral, health, and educational sciences to analyze both cross-sectional and longitudinal data. For UTK students, faculty, and staff, Mplus is available on the OIT Apps@UT server and on the computers in the OIT public computer labs. Up to four people can run it at the same time.

 Mplus Version 9 brings powerful methodological advancements, featuring expanded Penalized Structural Equation Modeling (PSEM), three-level Dynamic Structural Equation Modeling (DSEM), and enhanced multi-step mixture modeling. These updates equip researchers with advanced diagnostic tools and greater flexibility for handling complex longitudinal and multilevel data. 

Methodological Advancements in Mplus Version 9

• Expanded Penalized SEM (PSEM): Regularized structural equation modeling has been vastly extended. PSEM is now available for three-level continuous variable models, two-level mixture models, and categorical variables using WLSMV. It is especially useful for investigating direct effects in Latent Class Analysis (LCA). 

• Three-Level DSEM (Experimental): Researchers conducting intensive longitudinal data analysis can now implement three-level dynamic structural equation modeling using Bayesian estimation. 

• Enhanced Mixture Modeling: Version 9 introduces TYPE=IMPUTATION for multi-step mixture modeling, improved AUXILIARY option settings, and enhanced automated capabilities for 3-step and BCH approaches. 

• Advanced Diagnostics: New built-in tools for assessing model fit include the Variance Inflation Factor (VIF) to detect collinearity among covariates and Effective Sample Size (ESS) calculations for Bayesian models. 

Learning & Resources 

To get up to speed on these additions, the Mplus development team has released detailed Web Talks. Web Talk 9 focuses specifically on using PSEM to investigate direct effects in LCA, while Web Talk 8 covers multistep mixture modeling. For a full breakdown of syntax updates and commands, you can consult the Mplus website.