Hi Steve,
thanks a lot for the kind answer. I will try to familiarize myself with
TFCE. However, is there, in principle, a way to calculate the p-values
from our presets?
Best
Markus
> Hi Markus,
>
> "Minimum cluster extent" isn't an explicit part of any of the
> thresholding programs. However, if you're doing cluster-based
> thresholding in FEAT or with randomise, then the final cluster
> corrected p-value, when thresholded at say p<0.05, is exactly
> _equivalent_ to setting a minimum cluster extent (but specified via
> the corrected p-value, not cluster size) - so you don't have to
> specify this yourself.
>
> Still, better to use TFCE.....
>
> Cheers.
>
>
>
> On 15 Feb 2009, at 16:39, Markus Ploner wrote:
>
>> Hi,
>>
>> a very simple thresholding question:
>>
>> I have a map with uncorrected p-values (e.g. 0.001), a mask for a
>> priori
>> defined regions of interest and I assume a minimum cluster extent
>> (e.g. 10
>> voxels). How can I calculate which (FDR and FWE)-voxel-corrected p-
>> value
>> corresponds to my presets (uncorrected p-value, mask and minimum
>> cluster
>> extent)?
>>
>> Thanks a lot
>>
>> Markus
>>
>>
>>
>
>
> ---------------------------------------------------------------------------
> 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
> ---------------------------------------------------------------------------
>
>
--
Dr. Markus Ploner
Humboldt Research Fellow
FMRIB Centre
University of Oxford
Fon 0044-1865-222488
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