Dear FSL experts,
A question about running randomise on 3 groups of FA data, partly following the
"tbss on subgroups" post:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0906&L=FSL&P=R27740&1=FSL&9=A&I=-3&J=on&d=No+Match%3BMatch%3BMatches&z=4
If I include all groups in the design matrix and want to test the difference
between group 1 and 2, would the dummy codes for these two groups also enter the
time series block of group 3 in certain randomisation runs so that group members
are not exclusive in those runs? Or would randomisation only happen among group
1 and group, with group 3 screened out?
Also another question about design matrix in this case:
I found in some posts the design is set up in the way that a full column of '1'
is used for baseline group mean and the other two (1,0) columns are used for
differences from the baseline group, which is like the treatment contrast in R
etc. Is this preferred for randomise purpose to the way in which all group means
are modeled separately with (1,0) columns? I realize that the contrasts are not
the same.
Thanks in advance for any feedback!
Best, Daqiang
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