As discussed in Chen et al. (2014), EXC (9) can be tested through two methods, one univariate testing for the interaction (XUV), and one multivariate testing for the interaction (XMV). More specifically, with XUV one tests the equality among the m components in (9) by treating them as the m levels of a within-subject factor in an AN(C)OVA or univariate GLM platform. In contrast, the equality among the m components in (9) is tested in XMV as m simultaneous variables in an MAN(C)OVA or multivariate GLM (Appendix B).