Parameters | Workflows | Variance Component Effects

Variance Component Effects
Use this text field to specify effects defining sources of variability.
These effects are modeled to explain variability in the principal components . Variance components are estimated for each effect and then combined into a single pie chart of total variability in the principal components.
At least one variance component effect must be specified in order to produce results.
A residual variance component is also fitted that models all variability not accounted for by the effects.
For purposes of modeling additivity, all effects specified here are treated as random effects , even though you might normally consider them to be fixed effects in an ANOVA analysis.
Effects typically contain one or more Class Variables , which must also be specified.
To Specify Variance Component Effects
If you specify more than one 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 effects.
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 .
An at-sign ( @ ) can be used to limit the number of interactions. For example, typing A|B|C@2 removes the three-way interaction term.
Variance components modeling is not performed when With Variables are specified.