Central to the idea of variance components models is the idea of fixed and random effects. Each effect in a variance components model must be classified as either a fixed or a random effect. Fixed ...

That is, linear models with fixed effects and random effects. Some topics we’ll discuss are: When would I want to use a random effect? How does estimation change for random versus fixed effects? How ...

To determine appropriate means squares for testing the effects in the model, the TEST option in the RANDOM statement performs the following. For arguments in favor of not assuming that terms involving ...

Still, researchers are often interested in examining the effects of policy changes or other decisions. In those analyses, researchers will face any number of analytical decisions, including whether to ...