Hi Markus
> dear list.
>
> i received an offline answer about my question concerning parametric
> modulation which i like to allocate.
> the recommendation was, to perform a conjunction analysis with 2 t-
> contrasts (a<b, b<c) for each subject at first level and to enter the 2 con-
> images per subject into a 2x2 ANOVA (2 groups, 2 images) at second level.
> with this i do not have to assume a true linear increase stimulation load
> between the 3 conditions (a,b,c).
>
As explained before, I think a multiple regression model would really
suit better with [1 3 5] for a real linear contrast, or [-1 1] U [-1 1]
for possible non linear effect .. the ANOVA solution was mainly because
you didn't seem up to more 'sophisticated' model ..
cyril
> thanks for the help
>
> markus
>
>
>
--
Dr Cyril Pernet,
fMRI Lead Researcher SINAPSE
SFC Brain Imaging Research Center
Department of Clinical Neurosciences
University of Edinburgh
Western General Hospital
Crewe Road
Edinburgh
EH4 2XU
Scotland, UK
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tel: +44(0)1315373661
http://www.dcn.ed.ac.uk/bic/
http://www.dcn.ed.ac.uk/bic/sinapse/sinapse.asp
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