Dear all,
I‘ m analyzing a repeated-measures design with 2 groups of subjects by means
of “flexible factorial ANOVA” design. After estimating the design I get the
“invalid contrast” message, when specifying contrasts for the main effects of
time and group. I’m not sure if my design or my specified contrast is the
problem.
The design was set up as follows:
Factors
1. Subject (independ-> yes/var -> equal)
(29 subjects)
2. Group (independ-> yes/var -> unequal)
(2 groups)
3. Time (indpend-> no / var -> unequal)
(2 time points)
Main effects: 1 / 2/ 3
Interaction 2,3
(see attached design-matrix)
Now I try to specify the main effect of group (t contrast)
(29 zeros for the subject factor) 1 -1
--> “invalid contrast”
However, specifying the contrast for interaction (t contrast)
(29 zeros subject) (2zeros group) (2zeros time) 1 -1 -1 1 works fine
Questions:
a) What am I doing wrong specifying the contrast for the main effects?
b) Is the contrast for interaction correctly specified?
Thanks & kind regards,
Ben
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