Hi,
Each EV is in effect task vs. rest, so yes a [-1 -1 -1] (equivalent to
your contrast) does the rest > mean-task contrast that you want.
Cheers.
On 6 Dec 2008, at 10:44, Cornelius Werner wrote:
> Hi there,
>
> I searched the archives without apparent success, so I need to put up
> the question myself.
>
> I have a simple 3-condition block design paradigm, interrupted by
> resting period. I modeled all three active conditions, leaving the
> rest
> period unmodeled. Now, I would like to see the "inverse" contrast,
> i.e.
> "rest" > (task1 + task2 + task3). As far as I understood, there is no
> way of getting an unmodeled condition into a contrast. I tried to
> create
> a contrast like
>
> - -0.33 -0.33 -0.33
>
> in the hope that the resting codition would receive an implicit
> contrast
> weight of 1, but results are very unconvincing.
>
> What could a solution look like?
>
> Thanks for any help!
> Cornelius
>
>
>
> --
> Dr. med. Cornelius J. Werner
> GnuPG Public Key ID: 0x9D64BC2C
>
> Institute of Neuroscience and Biophysics - INB3
> Research Centre Juelich
> 52425 Juelich
> Germany
>
> Department of Psychiatry and Psychotherapy
> RWTH Aachen University
> Pauwelsstr. 30
> 52074 Aachen
> Germany
>
> ::: Please encrypt confidential data :::
>
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