+++From feat5.pdf+++
Paired Two-Group Difference (Two-Sample Paired T-Test)
We have a group of 8 subjects scanned under two different conditions, A and
B. We enter the condition A analyses as the first 8 inputs, and the
condition B analyses as the second 8 inputs. Make sure that the subjects
are in the same order within each group of 8! We need one EV for the A-B
differences, and then one extra EV for each subject, making 9 in all. EVs 2-
9 model each subject's mean effect - in this analysis this is a confound,
i.e. parameter estimates 2-9 are ignored, but without this part of the
model, the mean effects would intefere with the estimation of the A-B
paired differences. A contrast with a one for EV1 and zeros elsewhere tests
for A-B paired differences.
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My question is to extend this to 3 conditions, A, B, and C, say for 5
subjects. So should I have first three EVs model the pair-wise comprisons
between any two conditions AB, AC, and BC, and then another 5 EVs to model
the subject mean effect, as below? Thanks.
Group EV1 EV2 EV3 EV4 EV5 EV6 EV7 EV8
1 1 1 0 1 0 0 0 0
1 1 1 0 0 1 0 0 0
1 1 1 0 0 0 1 0 0
1 1 1 0 0 0 0 1 0
1 1 1 0 0 0 0 0 1
1 -1 0 1 1 0 0 0 0
1 -1 0 1 0 1 0 0 0
1 -1 0 1 0 0 1 0 0
1 -1 0 1 0 0 0 1 0
1 -1 0 1 0 0 0 0 1
1 0 -1 -1 1 0 0 0 0
1 0 -1 -1 0 1 0 0 0
1 0 -1 -1 0 0 1 0 0
1 0 -1 -1 0 0 0 1 0
1 0 -1 -1 0 0 0 0 1
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