Dear Sir,
I was to quick to post the previous letter as I have some more concerns.
Firstly I would like to know if the approach I described in my first post
was not only less convenient but essentially wrong (I mean getting the
average activation for region and so on). To say truth this approach I
described appeals to me as I can for example include a covariate over time
(say Heart Rate of Skin Conductance) in further statistical analysis – this
would be impossible having only mean percent of the signal change.
Secondly I am not sure what I would be doing with the mean percentage change
in SPSS if I have only one group of subjects. That is I imagine that I would
be able to get only some descriptive statistics regarding the group mean of
the mean change of signal but I can not imagine conducting any statistical
inference – as there would be no factor neither between groups nor within
groups.
Best regards
Michal Kuniecki Ph.D.
Dpt. of Psychophysiology
Institute of Psychology
Jagiellonian University
Al. Mickiewicza 3
31-120 Kraków
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