What are the assumptions of multifactorial ANOVA?

What are the assumptions of multifactorial ANOVA? 



normal distribution
homogeneity of variance (one way of telling =
similar SD values, e.g. 3.97, 3.73, 3.09, 4.22)

If more than two conditions in any of the within-factors IVs, have to check whether the assumption of sphericity has been violated: Mauchley's test of sphericity
Sphericity= an assumption of within participant's ANOVA
If Mauchley's test of sphericity 's sig is 0.5 or lower, then this means the assumption of sphericity is violated, use Greenhouse Geisser

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