Print

Print


In doing PPI analysis, the AR(1) term is recomputed for each model (e.g.
each seed region). Since the goal of AR(1) is to remove the autocorrelation
from the data and its computed at the first level, does it also need to be
computed for each PPI model? Since the temporal autocorrelation in the data
is the same, I was thinking that one could use the AR(1)
parameters/estimates from the first-level model instead of re-estimating
the AR(1) term. Does anyone have any thoughts on using the AR(1) term from
the first-level versus re-estimating it for each and every seed region?

The estimates seem to change slightly between the first level and each ppi
seed region.

Best Regards, Donald McLaren
=================
D.G. McLaren, Ph.D.
Postdoctoral Research Fellow, GRECC, Bedford VA
Research Fellow, Department of Neurology, Massachusetts General Hospital
and
Harvard Medical School
Website: http://www.martinos.org/~mclaren
Office: (773) 406-2464
=====================
This e-mail contains CONFIDENTIAL INFORMATION which may contain PROTECTED
HEALTHCARE INFORMATION and may also be LEGALLY PRIVILEGED and which is
intended only for the use of the individual or entity named above. If the
reader of the e-mail is not the intended recipient or the employee or agent
responsible for delivering it to the intended recipient, you are hereby
notified that you are in possession of confidential and privileged
information. Any unauthorized use, disclosure, copying or the taking of any
action in reliance on the contents of this information is strictly
prohibited and may be unlawful. If you have received this e-mail
unintentionally, please immediately notify the sender via telephone at
(773)
406-2464 or email.