Hi Jane,
This sounds like you have done everything correctly.
The "time series" plots that are generated at the higher level
actually reflect the parameter estimates (copes) across
session/subject, not across time. So you expect to see
some form of zig-zag shape as this reflects the variability
of the response from session to session (or subject to
subject if that's what your higher level analysis is across).
If you are getting sensible activations and there are no
obvious "outliers" in these "time series" plots (which could
indicate a potential failure of one of the individual session
analyses) then it sounds like everything is fine.
All the best,
Mark
Jane Aspell wrote:
>hi
>thanks for the advice with my previous problems. this one kind of follows
>on...the time series plots for my higher level analysis (i was averaging
>together the results of 5 identical runs/series) look really bad. the full
>model and cope model fits are both straight lines and my data is a kind of
>zig zag shape!
>is this because of how i set up my EVs and contrasts?...i had one EV and one
>group (as i wanted to get the average over the runs for each of my 4
>contrasts ) and so i had one column in the design matrix with ones in each
>element.
>so in other words - is it ok that the time series look like this or has
>something gone wrong? the activations look fine and the analysis seems
>otherwise to have worked.
>
>thanks again
>
>jane
>
>
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