As well as exploring patterns of variation , Multivariate statistical methods can be used to test statistical hypotheses about factors that affect shape and to visualize their effects .
PCA is not needed for this purpose unless the method requires inverting the variance - covariance matrix .
As well as exploring patterns of variation , Multivariate statistical methods can be used to test statistical hypotheses about factors that affect shape and to visualize their effects , although PCA is not needed for this purpose unless the method requires inverting the variance - covariance matrix .