Can someone help me understand how the two threshold values are used (and in what order) in the 'cluster' command? I am running cluster Version 1.3.
For example, I am running this command:
set opt = "--zstat=zstat2 --dlh=0.0356698 --volume=201512 --pthresh=0.05"
set opt = "$opt --minclustersize --mm"
cluster $opt --zthresh=2.5
And get these results:
Minimum cluster size under p-threshold = 390
Cluster Index Voxels P -log10(P) Z-MAX Z-MAX X (mm) Z-MAX Y (mm) Z-MAX Z (mm) Z-COG X (mm) Z-COG Y (mm) Z-COG Z (mm)
2 532 0.0108 1.97 4.02 -8 -54 42 -1.74 -59.5 41.7
1 424 0.0341 1.47 4.42 44 -60 -16 47.6 -65.2 -18
Where --zthresh=2.5 --> p=0.006210
% ztop 2.5
0.006210
Is the --zthresh=2.5 applied to zstat volume first, thereby creating clusters of surviving voxels, and then --pthresh=0.05 is used to determine if each cluster has a probability of < 0.05 of being due to noise?
Thank you,
- BettyAnn
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