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two way ANOVA with unequal sample sizes

julien claude <claude at isem.univ-montp2.fr> writes:
Ahem. Tab damage detected... and your command and output don't match
up. 


The as.factor(gender:bonedevlopment) is playing with fire... You
should calculate factor() of each term. However, it would seem that
you already did manage to convert things to factors or you would have
gotten something to this effect:
[1] 1
Levels:  1 
Warning messages: 
1: Numerical expression has 14 elements: only the first used in:
gender:bone.development 
2: Numerical expression has 14 elements: only the first used in:
gender:bone.development
I don't think we're the ones with the problem... There are various
boneheaded ways in which people try to use to assign some kind of
SumSq to main effects in the presence of interaction, and they are all
wrong - although maybe not very wrong if the unbalance is slight.

The tests *should* depend on the test order, as is most clearly seen
if the predictors are highly collinear.