Use the text field to specify additional variables or effects by which to model the covariance structure of the response variable.These effects typically comprise class variables and their interactions.Caution : Do not repeat any effects here that are already specified as Fixed Effects .
Type one or more random effects in the text field.
If you specify more than one fixed effect then you must separate the effects with spaces . For example, assuming A and B are listed as Class Variables , typing A B in the text field specifies variables A and B as main fixed effects .
To specify interactions between effects, type an asterisk ( * ) between the effects. For example, assuming A and B are listed as Class Variables , typing A B A*B specifies variables A and B , and the interaction between A and B as fixed effects and constructs a two-way ANOVA model.
A vertical bar ( | ) can be used to create main effects and interactions. For example, typing A|B is the same as typing A B A*B .