But note that in this scenario there would be no main effects for either rows or columns (Mrow1=Mrow2=7.5 and Mcol1=Mcol2=7.5), notwithstanding that drugs A and B are obviously having an effect when presented separately. The moral of this story is that the interpretation of the presence or absence of main effects in a two-way ANOVA is not always simple and straightforward. More of this later.
Would you like to comment?
Join Diigo for a free account, or sign in if you are already a member.