AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

History of AFNI updates  

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Kai
April 14, 2015 10:25AM
Thank you Ziad and Rick!

I think I understand why the standard deviation from independent t test was different from 3dttest++ now.
When we run the two sample t test, the beta value in that ROI is a single number with a standard deviation of zero.
When we run 3dttest++, it is voxel-wise test, the beta value in that ROI is a mean of lots of voxels with a standard deviation not equals zero.
That’s why the mean is always the same, but the standard deviation is not the same.
I will try to run it with a single voxel to see if it is the same.

Thank you again Ziad and Rick!

Kai
Subject Author Posted

3dROIstats

Kai April 13, 2015 11:48AM

Re: 3dROIstats

Kai April 13, 2015 02:47PM

Re: 3dROIstats

ziad April 13, 2015 05:26PM

Re: 3dROIstats

rick reynolds April 14, 2015 12:58AM

Re: 3dROIstats

Kai April 14, 2015 10:25AM