Hi everybody,

I'm running 3dClustSim to get the minimal cluster size for some analyses. I'd like an athr of 0.0125 (0.05/4) but the report produced by 3dClustSim list 0.013 for the athr. I know in the grand scheme of things that 0.005 may not make a huge difference, but I'd still like to know whether 3dClustSim is rounding the 0.0125 to 0.013 in the output or rounding it to 0.013 before running the simulation. Can
anyone shed some light on this?

Thanks in advance,
Colm.
--
# 3dClustSim -mask ../../standard/MNI152_T1_3mm_brain.nii.gz -fwhm 4.2 -niml -prefix CStemp.alpha=0.0125.fwhm4.2 -athr 0.0125
# Grid: 61x73x61 3.00x3.00x3.00 mm^3 (67665 voxels in mask)
#
# CLUSTER SIZE THRESHOLD(pthr,alpha) in Voxels
# -NN 1 | alpha = Prob(Cluster >= given size)
# pthr | 0.013
# ------ | ------
0.100000 249.9
0.090000 196.6
0.080000 154.3
0.070000 120.0
0.060000 93.4
0.050000 74.1
0.040000 57.4
0.030000 43.8
0.020000 32.0
0.015000 26.1
0.010000 20.1
0.007000 16.8
0.005000 14.1
0.003000 11.4
0.002000 9.6
0.001500 8.7
0.001000 7.6
0.000700 6.7
0.000500 6.1
0.000300 5.2
0.000200 4.6
0.000150 4.3
0.000100 3.8
0.000070 3.5
0.000050 3.2
0.000030 2.8
0.000020 2.6
0.000015 2.4
0.000010 2.2