Andrew - one possibility is that you don't have any clusters whose
size falls between the .05 and .01 thresholds - in this case, you
would not see any difference between the analyses
cheers
russ
On Feb 1, 2006, at 6:16 AM, Andrew Silver wrote:
> I am having difficulty understanding how the cluster P threshold
> works. I
> did an analysis on a single run of a subject using a Z threshold of
> 2.3
> and a P threshold of 0.05. Then, I re-did the analysis, however I
> changed
> the P value to 0.01, but left the Z value unchanged. My activation
> results from the 2nd analysis were identical to the first
> analysis. So,
> my question is, what effect is there from changing the P value,
> without
> changing the Z value. Thanks.
> -Andy
---
Russell A. Poldrack, Ph.d.
Assistant Professor
UCLA Department of Psychology
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phone: 310-794-1224
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web: www.poldracklab.org
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