Screenshot from Matlab 2013a
On 5 October 2016 at 12:30, Verónica García <[log in to unmask]> wrote:
> Dear Marko and Guillaume,
>
> Thank you for your emails. We used the same preprocessed dataset as an
> input for the statistics step (flexible factorial) in all cases
> (MATLAB R2013a, MATLAB R2015a and MATLAB R2016b). I have attached the
> screenshots of the results in the following email (I have some
> problems with the message size)..
>
> The significant voxels are located in a small volume within the brain
> because the image dataset doesn´t belong to human beings.
>
> Looking at the results, you can see for example:
>
> 1) Matlab R2013a: p(set-level) = 0.782 and the voxels of the
> cluster-level are 1052 in total.
> 2) Matlab R2015a: p(set-level) = 0.789 and the voxels of the
> cluster-level are 1137 in total. So the difference compared to Matlab
> R2013a is 0.9% in p(set-level) and 8.1% in number of voxels.
> 3) Matlab R2016b: p(set-level) = 0.903 and the voxels of the
> cluster-level are 888 in total. So the difference compared to Matlab
> R2013a is 15.5% in p(set-level) and 15.6% in number of voxels.
>
>
> Guillaume, tell me if it is really necessary to send you the copy of
> the folders containing the SPM.mat because I am not be sure if I am
> allowed to do that.
>
> Just in case it is important, Matlab was installed using its default
> settings. I didn´t remove any Matlab toolbox from the default Matlab
> installation list.
>
> Best regards!
>
> Verónica
>
> On 5 October 2016 at 11:24, Guillaume Flandin <[log in to unmask]> wrote:
>> Hi Veronica,
>>
>> as Marko mentioned, it would be great if you could show us the
>> differences you observe in the results you obtain when the only change
>> is the MATLAB version (screenshot of the Result page and, possibly, copy
>> of the folders containing the SPM.mat). I would not expect significant
>> differences so it would be interesting to get to the bottom of this.
>>
>> Best regards,
>> Guillaume.
>>
>> On 05/10/16 07:11, Marko Wilke wrote:
>>> Veronica,
>>>
>>> while I do not have an answer, I believe it would be most helpful if you
>>> could quantify the differences (are they on the order of .01%, 1%, or
>>> 10%?), and report on how exactly you have made sure that the error is
>>> only in the statistics steps (are these datasets identical, or
>>> preprocessed identically in the different versions, or...). This may
>>> also help to narrow it down to a real glitch or rounding differences or
>>> whatever else.
>>>
>>> Cheers
>>> Marko
>>>
>>> Verónica García wrote:
>>>> Dear SPM experts,
>>>>
>>>> Which is the most appropriate version of MATLAB when using SPM12
>>>> v6685? I am asking that question because we are comparing a set of PET
>>>> images using a Flexible Factorial design (basic models) and the
>>>> results are not the same if we use MATLAB R2013a, MATLAB R2015a or
>>>> MATLAB R2016b.
>>>>
>>>> Thank you for any help you can provide.
>>>>
>>>> Best regards
>>>>
>>>> Verónica García Vázquez
>>>>
>>>
>>
>> --
>> Guillaume Flandin, PhD
>> Wellcome Trust Centre for Neuroimaging
>> University College London
>> 12 Queen Square
>> London WC1N 3BG
|