Note that the GLM procedure allows homogeneity of variance testing for simple one-way models only. Homogeneity of variance testing for more complex models is a subject of current research. Bartlett ...

Negative Variance Component Estimates The variance components estimated by PROC VARCOMP should theoretically be nonnegative because they are assumed to represent the variance of a random variable.

The formula for the Wilks’ Lambda test statistic in MANOVA is: Where E is the within-group covariance matrix, which measures variability of the outcome variables within each group of the explanatory ...