Hi,
There are two main options. You could pass up separate contrasts, and
model each with its own group-mean (etc) regressor at group level, and
then do a high-level F-test across those, but that loses some of the
point of the flexibility of having multiple HRF basis functions (etc)
at first level.
Alternatively you could apply the standard space registrations to your
fstat images, and use randomise across subjects at higher level. This
takes more fiddling on the command line, and doesn't make use of the
Bayesian modelling and variance weighting that you get in FLAME (in
higher-level FEAT).
As I said, we're working on combining the best of these approaches in
the future.
Cheers.
On 14 Feb 2009, at 18:27, Yael Shani wrote:
> Hi Steve
> Thank you for your reply.
> So, if I want to see the activation of combined contrasts in second
> and third level analysis, is there a way to do so?
> Thanks again
> Yael
>
> On Sat, Feb 14, 2009 at 11:00 AM, Steve Smith <[log in to unmask]>
> wrote:
> Hi, I'm afraid that at present it is not possible to pass f-tests up
> to higher-level FEAT analyses as FLAME is only implemented for
> feeding COPEs up into it. This is something we're working on for the
> future.
>
> Cheers, Steve.
>
>
>
> On 13 Feb 2009, at 15:14, Yael Shani wrote:
>
> Dear fslers
>
> I ran first level analysis in 15 subjects. For each of them I
> created an F test to examine the combined effect of 2 contrasts.
> When I run second level analysis, I have the option to use the
> contrasts but I can't find the F test used in the first level.
> How can I use it/ find it?
> Many thanks
> Yael
>
>
> ---------------------------------------------------------------------------
> Stephen M. Smith, Professor of Biomedical Engineering
> Associate Director, Oxford University FMRIB Centre
>
> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
> +44 (0) 1865 222726 (fax 222717)
> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
> ---------------------------------------------------------------------------
>
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Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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