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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September 11, 2018 10:39AM
Hello,

I am analyzing resting state data and usually use 3dttest++ with -Clustsim option to do a seed based group analysis. It looks like this option uses the input to 3dttest which is the final seed-based results obtained from 3dDeconvolve. I recently ran a 3 level 3dAnova and was a little confused about whether the stats are FDR corrected. The output from anova_bucket dataset shows significance (at least I think that is what the asterisks mean) :
-- At sub-brick #0 'group_f:Inten' datum type is short: 0 to 32767 [internal]
[* 1.48214e-05] 0 to 0.485652 [scaled]
-- At sub-brick #1 'group_f:F-stat' datum type is short: 0 to 1035 [internal]
[* 0.01] 0 to 10.35 [scaled]
statcode = fift; statpar = 2 26
-- At sub-brick #2 'AI_m:Mean' datum type is short: -5718 to 32767 [internal]
[* 2.33344e-05] -0.133426 to 0.764599 [scaled]
-- At sub-brick #3 'AI_m:t-stat' datum type is short: -5440 to 32700 [internal]
[* 0.001] -5.44 to 32.7 [scaled]


And when I open the dataset in the GUI, there is an associated q value (the p and q values change automatically depending on which sub-brick you have as overlay and threshold - when I look at t-test results, it's only the q value that changes and the p value stays constant unless you manually change it - why is that?) but I wasn't sure how to only show the clusters that are FDR corrected. I tried to run 3dClustSim and based on these threads, I thought the less processed file, as you stated here, should be used to determine acf values etc.... But now I am confused because of how 3dttest++ runs it. Should I try to use the file generated immediately prior to regressing out wm and csf noise? or should the acf values come from a dataset that is not blurred?

Thanks for your help!
Subject Author Posted

3dClustsim

sharyn September 11, 2018 10:39AM

Re: 3dClustsim

rick reynolds September 21, 2018 10:07AM