Hi all,
I would like to know whether the residual variance in two groups of subjects
is different. I have the ResMS.img from the single-subject analyses and, to
see what happens, entered them into a Basic Models 2-sample t-test. This
shows significant differences in variance in the direction I expect. I have
two questions:
1) Is this way of comparing the groups valid given that the individual
images contain within-subject variances?
2) I note that the significant difference occur outside the regions showing
a significant main effect of task when analysed conventionally. Is there an
inherent reason why this should be so?
Thanks a lot,
And nice weekend to all,
Andreas Meyer-Lindenberg
Andreas Meyer-Lindenberg, M.D., Ph.D. (PD Dr. med.)
Unit on Integrative Neuroimaging, Clinical Brain Disorders Branch, National
Institute of Mental Health
Bldg. 10 Room 4C101, 9000 Rockville Pike, Bethesda, MD 20892-1365, USA
email: [log in to unmask], phone: 301-496-9672, fax: 301-496-7437
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