The min/max/etc are the voxel wise measures. When you use --accumulate, it sums all the voxels but does not divide by the number of voxels, so you get a number much larger than any one voxel doug
On 9/3/14 9:44 PM, SHAHIN NASR wrote:
Hi Surfers,
I want to measure the average amount of myelinations within my ROI(s), I have already generated my myelination maps on surfaces (e.g.lh.myelin_ProjFrac0p5.nii ). Then I used mri_segstats as below:
mri_segstats --i lh.myelin_ProjFrac0p5.nii --slabel SBJ_001 lh lh.V1 --sum V1_Stats.txt --accumulate
but the numbers don't make any sense. For instance:
# ColHeaders Index SegId NVertices Area_mm2 StructName Mean StdDev Min Max Range 1 0 125261 82573.4 Seg0000 110280.4453 0.2922 -5.5000 51.0000 56.5000 2 1 1138 764.8 Seg0001 941.0988 0.1572 0.2675 1.4203 1.1527
How can mean=941.0988 when the max=1.4203 ???
Regards
Shahin Nasr
PhD in Cognitive Neuroscience Martinos Imaging Center, MGH Harvard Medical School
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