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  

|
March 27, 2006 04:22PM
> I am concerned that if we have the same stimulus feature
> repeated in a clip - which happens quite often (and in fact more
> often for 2 of the three stimulus features which is unavoidable), we
> will run out of power for decovolution (which as far as I understand
> it assumes linearity). For example, if we have a clip that is 12
> seconds long (6 TR's), and has the same feature in every TR, if we
> mark every TR, we will end up with a 1D file that has six ones in a row.


If power is a mjor concern, how about if you adopt a fixed model such as Gamma instead of deconvolution? Since the stimuli are more or less of block type, a fixed model might not be a bad idea. Or try both, and see how it goes.

Gang
Subject Author Posted

variable stimuli

Susan Wagner Cook March 23, 2006 01:00PM

Re: variable stimuli

Gang Chen March 24, 2006 02:51PM

Re: variable stimuli

Susan Wagner Cook March 24, 2006 05:53PM

Re: variable stimuli

joan fisher March 26, 2006 10:30AM

Re: variable stimuli

Gang Chen March 27, 2006 10:59AM

Re: variable stimuli

Gang Chen March 27, 2006 10:37AM

Re: variable stimuli

Susan Wagner Cook March 27, 2006 02:51PM

Re: variable stimuli

Gang Chen March 27, 2006 04:22PM

Re: variable stimuli

Susan Wagner Cook March 27, 2006 04:45PM