I performed a 2-way ANOVA with one between- and one-within subject factor
in SPM5. For the between-subject factor, I set SPM to allow inhomogeneity
of variance; for the within-subject factor, I allowed both inh of var as
well as non-independence of the factor levels.
I decided to compare that to the situation when I assume variance was
homogeneous and factor levels were independent.
The dof and F-statistic thresholds for a given p were identical. When I
plotted one image against another, it wasn't true that "corrected" F-
values were always lower than the "uncorrected" ones ("corrected"
referring to the inh of var and dependence corrections).
Is it possible?
