Choose your goal for multiple comparisons. On the next tab, you can choose exactly which test to use.
In many cases, the answers you really want are determined by multiple comparisons and not by the overall ANOVA analysis. Choose the comparisons you want to make on this tab, and then set the details on the next (Options) tab.
If you have 2x2x2 ANOVA, then the number of comparisons are:
•Compare each cell mean with every other cell mean: 28 comparisons
•Compare means that differ by only one factor: 12 comparisons
•Compare the control mean with the other cell means: 7 comparisons
•Compare each mean in row 1 with the cell mean just below it: 4 comparisons
If you have 2 x 2 x k ANOVA, then the number of comparisons are:
•Compare each cell mean with every other cell mean: 8k2-2k comparisons
•Compare the control mean with the other cell means: 2x2xk-1 comparisons