Hotelling´s T-Square:
Hotelling´s T-square is a statistic for a multivariate test of differences between the mean values of two groups. The null hypothesis is that centroid s don´t differ between two groups.
Hotelling´s T-square is used in multiple analysis of variance (MANOVA) , and in multiple analysis of covariance (MANCOVA) .
A related statistic is Hotelling´s Trace coefficient .