Hi Cutter,
I would agree that in a model with 44 subjects and no significant
voxels, something must have gone wrong. For one, have you checked the
mask image? If there is not enough overlap or sever data corruption,
this is a good place to start. Also, for checking several images, I sent
a snippet to the list a day or so ago, which I have now expanded to
generate a histogram of all assessed images (attached). This may make it
easier for you to find the guilty ones.
Cheers
Marko
Cutter Augustus Lindbergh wrote:
> Hi All,
>
> I continue to get the following error message when attempting to run
> Model Estimation in 2nd level analyses using a 2x2 flexible factorial
> design (SPM12b):
>
> /Failed 'Model estimation'
> /
> /Error using spm_est_non_sphericity
> /
> /Please check your data: There are no significant voxels /
>
> In searching the archives, I see that this issue has been raised before,
> and it's been recommended to check individual con files to look for
> suspicious data (e.g., using Check Reg). I've done this but haven't
> spotted anything unusual. (What also seems odd is that different
> combinations of the con files in my sample seem to work, which seems to
> suggest there's not just one bad subject causing the error).
>
> Any suggestions about how to proceed would be greatly appreciated. I'm
> at wit's end! In case it's helpful, I've attached screen shots of the
> error message and my design matrix.
>
> Thank you in advance for any help offered.
>
> Best,
> Cutter
>
--
____________________________________________________
Prof. Dr. med. Marko Wilke
Facharzt für Kinder- und Jugendmedizin
Leiter, Experimentelle Pädiatrische Neurobildgebung
Universitäts-Kinderklinik
Abt. III (Neuropädiatrie)
Marko Wilke, MD, PhD
Pediatrician
Head, Experimental Pediatric Neuroimaging
University Children's Hospital
Dept. III (Pediatric Neurology)
Hoppe-Seyler-Str. 1
D - 72076 Tübingen, Germany
Tel. +49 7071 29-83416
Fax +49 7071 29-5473
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http://www.medizin.uni-tuebingen.de/kinder/epn/
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