Dear all,
This is a rather arbitrary question, but I am curious if there is a general, accepted criteria
for setting up cluster z threshold and p threshold for whole-brain analysis at the group-level
(mixed effects FLAME 1). Would the default setting (z=2.3, p=.05) be good enough?
A second question is how I should interpret activation when I lower cluster threshold to,
say, z=1.6, but keep p=0.05. In this case, I do get clear activations at areas that conform
to my hypothesis, and it doesn't look like there are cluster activations all over the brain. In
my particular case, there is no cluster in the brain that satisfies the default criterion. And
that is why I lowered the z thresh.
The last question is what is the relation between 'cluster threshold' and 'uncorrected'? For
example, if a paper reports activation p<0.001 (uncorrected), what would that normally
correspond to when using 'cluster threshold'?
thanks
shihwei
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