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

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Aditya Prasad
October 08, 2008 10:12PM
I'm a little confused about how we're supposed to treat time intervals in our data which we want to ignore. This includes semi-rest periods, where we know there will be activation, but don't care about it.

If I don't introduce regressors for these areas, they'll contribute to the error term, making intersubject analysis harder for no good reason. If I do, it's not clear what sorts of regressors I need (perhaps one for each interval or something).

On a somewhat related note, do you have any suggestions on how I might go about picking gamma functions for my various task parts? I've read this:

[afni.nimh.nih.gov]

And it seems like I might want to stick with GAM(b, c) (after figuring out appropriate values for b and c).

Thanks!

(BTW, if you read this Rick, thanks for your help on the other threads).
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Ignoring time intervals

Aditya Prasad October 08, 2008 10:12PM

Re: Ignoring time intervals

Bob Cox October 09, 2008 09:55AM