SAS PROC MIXED is a flexible program suitable for fitting multilevel models, hierarchical linear models, and individual growth models. Its position as an integrated program within the SAS statistical ...

Hierarchical data analyses in different disciplines are reviewed to compare statistical applications of the Hierarchical Linear Model (HLM) software and the SAS MIXED procedure. Similar features of ...

A few other procedures in SAS/STAT software offer limited mixed-linear-model capabilities. PROC GLM fits some random-effects and repeated-measures models, although its methods are based on ...

This section introduces the mathematical notation used throughout this chapter to describe the mixed linear model. You should be familiar with basic matrix algebra (refer to Searle 1982). A more ...

Linear mixed models (LMMs) provide a powerful method for studying genotype–phenotype associations. Here the authors present a LMM application that estimates an optimal transformation from ...

Course TopicsThis course will discuss what mixed models are, why they are called "mixed" models, what is a "random factor", and why. The primary focus will be for the researcher to understand when he ...