Hi - you're right that easythresh isn't exactly the same, because it
uses the zstat image and not the residuals to estimate smoothness.
However in my experience it isn't ever very different. I suspect that
something's not comparable here - for example, are both approaches
using differently pre-masked images? How do the smoothness estimations
and voxel counts compare in the two cases?
Cheers.
On 24 Feb 2009, at 08:48, David Shirinyan wrote:
> I have been noticing this same issue but I have very large
> differences (ten
> fold) in the p values. FEAT output thresholded at Z=2 p=.05
> corresponds to
> an easythresh p threshold of p=.5. Is this large difference still
> due to
> smoothing estimation? Given this large discrepancy, how can I make
> use of
> easythresh? Are the easythresh images at p=.5 usable? Is easythresh
> unusable with my given dataset?
> Thank you in advance.
>
>
>
>
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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)
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