Hello All,
I wonder if anyone can help me with the following problem:
I am using SPM2 and need to extract the betas from each subject in a
second level analysis to analyse in SPSS. In an analysis without non-
sphericity correction it is easy – I go to my voxel, plot the effects of
interest and then type "Y" in the matlab window. This gives me a long
column which is number of subjects by number of regressors long (in my
case 24 subjects by 4 regressors = 96). I then put these numbers into
SPSS.
When I use non-sphericity correction I do the same thing but the numbers I
get out do not match the plot I get - i.e. the mean of the first twenty
four numbers does not match the value for the mean plotted in the graph
for the first regressor. I'm guessing that this has something to do with
the correlation matrix but as my maths is appalling that's as far as I got.
It would be great if anyone can tell me how to get each subject’s betas.
Thanks for any help you can give,
Geoff Bird
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