Hi:
I have a question about the factorial design script in SPM. We were
analyzing an FIR model and, unless I have misunderstood the script
algorithm, it seems to ignore the fact that the basis set contains multiple
columns that constitute a time effect in an ANOVA. So one cannot specify, in
the context of the script, that an F test should span the columns of the FIR
for each of several conditions. This can be specified manually.
In order to get around this we entered each condition as a series of little
FIR columns, i.e., condition A was split up into 9 separate conditions each
with an onset that was offset from the previous one by a TR. The factorial
design script then understood this.
I guess the same issue would hold for other designs in which the basis set
had more than one component.
Anyway I was wondering if this was a misunderstanding on my part, a feature
or the absence of a feature?
Darren
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