On 9/14/10 4:36 AM, Lucas Eggert wrote:
> Dear Tibor,
>> Dear Lucas,
>>
>> AFAIK, you cannot convert a z-map to FWE-p-map; but if your goal is to
>> threshold your z-map with FWE, then you can calculate the z(p=0.05
>> FWE) threshold with ptoz command with using the -g switch.
> That is exactly what I want to do: Determine the Z-value that represents
> a p-value of e.g. 0.05 (FWE-corrected).
>
> However, I do not understand what you mean with '-g switch'. Do you mean
> something like
>
> fslmaths zstat1.nii.gz -g -ptoz output.nii.gz?
>
> Thank you very much!
> -Lucas
% ptoz
Usage: ptoz <p> [-2] [-g <number_of_resels>]
-2 : use 2-tailed conversion (default is 1-tailed)
-g : use GRF maximum-height theory instead of Gaussian pdf
You want to use the ptoz command with the -g option.
Andrej
>>
>> Bests,
>>
>> Auer, Tibor M.D. Ph.D.
>> Biomedizinische NMR Forschungs GmbH
>> am Max-Planck Institut für Biophysikalische Chemie
>> Am Fassberg 11
>> 37077 Göttingen
>> Germany
>> Phone/Work: +49-(0)551-201-1725
>> Phone/Home: +49-(0)551-387-0076
>> Mobile: +49-(0)176-8012-7921
>> Mail: [log in to unmask]
>>
>>
>>
>> 2010.09.14. 12:32 keltezéssel, Lucas Eggert írta:
>>> Dear Experts!
>>>
>>> How can I determine the FWE-corrected p-Value for a given Z-value?
>>>
>>> I tried
>>>
>>> fslmaths zstat1.nii.gz -cpval fwe-corrected.nii.gz
>>>
>>> ... but that results in an image with only values of 1 in every voxel.
>>>
>>> Best wishes,
>>> -Lucas
>>>
>>
>>
>
>
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