Hi,
The mask works for other analysis. I created it with Imcalc (i1>0).
However, there are non-1 values especially at the border (even after
running Imcalc again).
Tried also setting "Implicit Maks: No". Yet, it didn't help.
Strangely, if I split the 2x2 design in two 2x1 designs the analyses are OK.
Any other suggestion?
I will try to debug as Darren suggested (hoping I don't get lost in
SPM variables).
Dorian.
2009/10/20 Mohammed Al-Rawi <[log in to unmask]>:
> Hi
> May be you can try a mask with all 1's....and see if the problem persists
>
> Regards
> Al-Rawi
>
>
> ________________________________
> From: Darren Gitelman <[log in to unmask]>
> To: [log in to unmask]
> Sent: Tue, October 20, 2009 4:37:44 PM
> Subject: Re: [SPM] No significant voxels because of the mask
>
> Dorian
>
> Are you sure your explicit mask lines up with your images? Are the
> values in your mask >0?
>
> I've checked the code and there doesn't seem to be an interaction
> between the various masks, e.g., an explicit mask shouldn't raise the
> threshold for implicit masking and vice versa. All the masks are
> intersected to give a final mask. Still, if you have other types of
> masking enabled you might try turning them off but leaving on the
> explicit mask and re-running the analysis.
>
> If you want to try to debug this, if no one else has other ideas, then
> you would look at line 680 in spm_spm and check if Cm is ever
> non-empty (these are the values loaded from your explicit mask). Then
> line 702 in spm_spm sets Y to the in-mask data (before any stats are
> done, but after all masking and thresholding).
>
> Darren
>
>
> On Mon, Oct 19, 2009 at 8:14 PM, Dorian P. <[log in to unmask]> wrote:
>> Dear all,
>>
>> I am running a flexible factorial with an explicit mask. The
>> estimations stops with error:
>>
>> -------------------------------
>> Error running job: Error using ==> spm_spm at 861
>> Please check your data: There are no significant voxels.
>> ------------------------------
>>
>> Nevertheless, when I remove the explicit mask, the estimation runs and
>> there are significant results (p < 0.001) in the areas that the mask
>> covers.
>>
>> Why does this happen? I thought using a mask the analysis would be
>> more sensible, not less.
>>
>> (using the last revision SPM5 r.3381)
>>
>> Thank you.
>> Dorian
>>
>
>
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