Hi - cope and varcope feed into forming the tstat and from there the
zstat, which is what gets thresholded. So thresholding has no effect on
either the cope/varcope, or on the higher-level analysis.
FEAT doesn't currently include FDR as an option - to use the fdr program
you need to run that from the command line after running FEAT. Your
question about allowing one to reduce the threhsold probably relates to
the GUI up and down arrows - if you highlight the text and type numbers in
you can change that.
Cheers, Steve.
On Mon, 5 Dec 2005, Junghee Lee wrote:
> Hello,
> I have a question of the effect of threshold method on cope1 and
> varcope1. I was wondering whether different methods of threshold
> produce different cope1 and varcope1 during the first level analysis.
> I'm trying to apply the fdr_threshold for z-stat images from the
> first level and then do the second level analysis.
>
> And I have another question. I'm trying to use the fdr_threshold
> instead of cluster threshold. And FEAT did not allow me to use the p-
> value less than .005. Does anyone know how to change this one?
> Thanks,
> Junghee
>
--
Stephen M. Smith DPhil
Associate Director, FMRIB and Analysis Research Coordinator
Oxford University Centre for Functional MRI of the Brain
John Radcliffe 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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