Other names for LMMs

Here are a bunch of different names that you might encounter that all refer to the same thing: a linear regression model that contains both fixed effects and random effects.

• linear mixed model (LMM)
• multilevel model (MLM)
• hierarchical linear model
  • but careful: some researchers in Psychology use “hierarchical models” to refer to a process also known as “stepwise regression”, so this is a label best avoided
• mixed effects model
• random effects model
• random coefficient model
• panel data model
• variance components model
• random parameter model
• mixed error-component model
• partial pooling model