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  

Previous Message Next Message
Message List New Topic Print View
|
gang
September 23, 2014 03:37PM
> I have a set of subjects that, for various reasons, may have 'dead' voxels in different voxels in their EPI
> data, where dead voxels will very between subjects. (By 'dead' I mean unchanging and zero.)

Use option -zskip in 3dttest++ to deal with such 'dead' voxels. The approach assumes that you don't have any (at least not too many) voxels where the *true* value is 0. 3dMEMA -missing_data is another approach if you have t-value available.

> It's not clear to me how to interpret the 'constant input data' clause when voxel A can be constant for
> some subjects, but not others.

The 'constant input data' clause is not really related to your 'dead' voxel situation. More specifically it refers to the situation when *all* subjects have a constant value at a voxel.

Gang



Edited 1 time(s). Last edit at 09/23/2014 03:42PM by Gang.
Reply Quote
RSS
Subject Author Posted

3dttest++, masks, and constant values

shanusmagnus September 23, 2014 02:06PM

Re: 3dttest++, masks, and constant values

gang September 23, 2014 03:37PM

Re: 3dttest++, masks, and constant values

shanusmagnus September 23, 2014 09:10PM

Re: 3dttest++, masks, and constant values

Peter Molfese September 23, 2014 03:49PM