Hi,
I'm preparing a dataset for a ROI-based granger causality analysis (in
Matlab). I will preprocess the data with slicetime and motion correction
and will try out no spatial smoothing and 6mm spatial smoothing.
I was wondering the following: would it be allowed to turn on
prewhitening prior to a granger causality analysis? If I would do so, I
can imagine this will result in far more robust estimates of temporal
(auto)correlation between successive dynamics because you eliminate the
temporal autocorrelated noise as much as possible. However, since I'm
not entirely aware of the underlying details of both methods (which are
probably related), I'm a bit worried that this will be a statistically
invalid/illegal approach, fi because of artificially lifting temporal
relations.
Thank you!
Andries van der Leij
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