Dear expertise,
I am using three basis functions to model my data on the first
level, the canonical HRF as well as its temporal and dispersion
derivatives. On the second level I then specify a 'full factorial'
model with one factor which has three levels, the basis functions. In
spm2 I looked at similar data with an F-contrast eye(3) to find areas
activated. In spm5 there is an automatically created contrast 'Average
effect of condition' which is ones(3). What is the difference between
these and which is the proper one to use.
Regards, Johan
--
Johan Sandblom MRC, N8, Karolinska Hospital
p +46 8 517 761 08 17176 Stockholm
m +46 73 552 14 77 Sweden
"What is wanted is not the will to believe, but the will to find out,
which is the exact opposite" -- Bertrand Russell
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