HI,
I would appreciate your advice on the following. We would like to perform a
two-way between groups ANOVA. The between-groups factor has four levels
[males no treatment (A), females no treatment (B), males treated (C) and
females treated (D)] and the within groups factor has three levels
(positive, negative and neutral words). We have a total of 24 subjects, 7 in
groups A and D and 5 in groups C and D. In a second level analysis we would
like to perform an ANOVA to investigate the main effect of group, the main
effect of valence and the interaction group*valence. The input to the
second level random effects analysis are the copes derived from the first
level analysis (from each subject). Below is our EV design matrix
(simplified to 1 subject per group).
Grp EV1 EV2 EV3 EV4 EV5 EV6 EV7 EV8 EV9 EV10 EV11 EV12
pos_A_sub_1 1 1 0 0 0 0 0 0 0 0 0 0 0
pos_B_sub_1 2 0 1 0 0 0 0 0 0 0 0 0 0
pos_C_sub_1 3 0 0 1 0 0 0 0 0 0 0 0 0
pos_D_sub_1 4 0 0 0 1 0 0 0 0 0 0 0 0
neg_A_sub_1 1 0 0 0 0 1 0 0 0 0 0 0 0
neg_B_sub_1 2 0 0 0 0 0 1 0 0 0 0 0 0
neg_C_sub_1 3 0 0 0 0 0 0 1 0 0 0 0 0
neg_D_sub_1 4 0 0 0 0 0 0 0 1 0 0 0 0
neu_A_sub_1 1 0 0 0 0 0 0 0 0 1 0 0 0
neu_B_sub_1 2 0 0 0 0 0 0 0 0 0 1 0 0
neu_C_sub_1 3 0 0 0 0 0 0 0 0 0 0 1 0
neu_D_sub_1 4 0 0 0 0 0 0 0 0 0 0 0 1
Below is the contrast matrix and f tests. Does F1 give the omnibus F test,
F2 the main effect of group, F3 the main effect of stimulus type and F4 the
interaction group*valence?
1 2 3 4 5 6 7 8 9 10 11 12 F1 F2 F3 F4
C1 1 -1 0 0 1 -1 0 0 1 -1 0 0 on on off off
C2 1 1 -2 0 1 1 -2 0 1 1 -2 0 on on off off
C3 1 1 1 -3 1 1 1 -3 1 1 1 -3 on on off off
C4 1 1 1 1 -1 -1 -1 -1 0 0 0 0 on off on off
C5 1 1 1 1 1 1 1 1 -2 -2 -2 -2 on off on off
C6 1 -1 0 0 -1 1 0 0 0 0 0 0 on off off on
C7 1 1 -2 0 -1 -1 2 0 0 0 0 0 on off off on
C8 1 1 1 -3 -1 -1 -1 3 0 0 0 0 on off off on
C9 1 -1 0 0 1 -1 0 0 -2 -2 0 0 on off off on
C10 1 1 -2 0 1 1 -2 0 -2 -2 4 0 on off off on
C11 1 1 1 -3 1 1 1 -3 -2 -2 -2 6 on off off on
many thanks for your help.
ray
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