I have a somewhat simple analysis to perform, but I'm not quite sure
how to set it up.
Let's say I have 3 subjects (S1, S2, S3), each scanned under conditions
A,B,C, and D.
I am interested in comparing A vs B and C vs D. But I am also
interested in the comparison (A-B)vs(C-D).
Would the following capture this?
Input EV1(S1 mean) EV2(S2 mean) Ev3(S3 mean)
EV4(AvsB) EV5(CvsD)
S1:A 1 0
0 1 0
S2:A 0 1
0 1 0
S3:A 0 0
1 1 0
S1:B 1 0
0 -1 0
S2:B 0 1
0 -1 0
S3:B 0 0
1 -1 0
S1:C 1 0
0 0 1
S2:C 0 1
0 0 1
S3:C 0 0
1 0 1
S1:D 1 0
0 0 -1
S2:D 0 1
0 0 -1
S3:D 0 0
1 0 -1
with contrasts:
C1 (A vs B): 0 0 0 1 0
C2 (C vs D): 0 0 0 0 1
C3 (a-b vs c-d): 0 0 0 1 -1
or do I need an EV to code the a-b vs c-d directly?
-BRad
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