data : ndarray
3D array where the first two dimensions are compliant
with a subjects X conditions scheme where the first
factor repeats slowest:
A1B1 A1B2 A2B1 A2B2
subject 1 1.34 2.53 0.97 1.74
subject ... .... .... .... ....
subject k 2.45 7.90 3.09 4.76
The last dimensions is thought to carry the observations
for mass univariate analysis.
factor_levels : listlike
The number of levels per factor.
effects : str  list
A string denoting the effect to be returned. The following
mapping is currently supported (example with 2 factors):
'A' : main effect of A
'B' : main effect of B
'A:B' : interaction effect
'A+B' : both main effects
'A*B' : all three effects
'all' : all effects (equals ‘A*B’ in a 2 way design)
If list, effect names are used: ['A', 'B', 'A:B'] .
alpha : float
The significance threshold.
correction : bool
The correction method to be employed if one factor has more than two
levels. If True, sphericity correction using the GreenhouseGeisser
method will be applied.
return_pvals : bool
If True, return p values corresponding to f values.
