[log in to unmask] said:
> Therefore, con_???.img does not include the intra-subject error
> information in it. In the SPM documentation, and in most of the
> letters I've read, it is mentioned that for second level analysis, we
> have to enter con_???.img files from each subject. Therefore, we
> exclude intra-subject variance from the second level analysis. So, why
> don't we enter the spmT_???.img into the second level analysis?
> Probably I'm missing something but I'll appreciate your inputs to this
> matter.
Because we want to establish reliable inter-subject effects for the
*parameter contrasts* of the model, not for the *t transforms* of those
contrasts. As your state these t statistics are *inversely weighted by
intra-subject variance*.
Ian
--
Ian Nimmo-Smith
MRC Cognition and Brain Sciences Unit
15 Chaucer Road, Cambridge CB2 2EF
Tel: +44 (0) 1223 355294 x 710 Fax: 359062
mailto:[log in to unmask]
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