On Mon, 19 Sep 2005, <Anson> <Chau> wrote:
> I would like to know which voxel has real activation that related to the
> paradigm but which is not. Can I use VOI at SPM99? Can I said if the voxel
> has the same pattern with the paradigm in 1st eigenvariate: VOI graph,
> then it is a real activation?
Dear Anson,
what SPM (and any other statistics) can tell you, is: "Can I reject my
null hypothesis (i.e. that there is no activation) with a certain risk of
false rejections?" If we were able to tell what is "real activation" and
what is not, then we would not need to do statistics...
If your pattern in eigenvariate and paradigm looks similar, then this is
some (possibly strong) evidence of a real effect, but this doesn't mean
that you can skip significance testing.
--
Volkmar Glauche
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Department of Neurology [log in to unmask]
Universitaetsklinikum Freiburg Phone 49(0)761-270-5331
Breisacher Str. 64 Fax 49(0)761-270-5416
79106 Freiburg
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