Hi
I would like to perform a grouped analysis on some FA data using randomise. The FA data has
been generated using tbss. The question I have relates to setting up the design matrix using the
GLM GUI. I would like to investigate the differences in WM tracts between two groups of subjects
given additional information (covariate), such as a cognitive score (eg a unpaired two-group
analysis with a confounding variable). If for argument sake the scores for 6 subjects (3 in each
group) were 21, 22, 23, 23, 22, 21, using the GLM GUI, I am not sure how to best set up the
contrasts. In the example below I have demeaned the scores (EV3).
Group EV1 EV2 EV3
Input1 1 1 0 -1
Input2 1 1 0 0
Input3 1 1 0 1
Input4 2 0 1 1
Input5 2 0 1 0
Input6 2 0 1 -1
Contrasts
EV1 EV2 EV3
C1 1 -1 ?
C2 -1 1 ?
Any help would be much appreciated.
Regards
Stephen
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