Dear Gabriel,
On Sun, 23 Jul 2017 22:25:29 +0100, gabriel robert <[log in to unmask]> wrote:
>Dear SPM/VBM experts,
>
>I am looking for a quick description of what the algorithm exactly does,
>
>Does is look for correlation of the mean values of all the voxels for each
>volumes against each other ? This is what I understand from the correlation
>matrix but I might be wrong.
No, it does calculate the correlation of all voxels (as vector) of one image with all voxels of another image. Then, the mean of all correlations of one image (to the remaining images) is calculated. The boxplot finally shows these mean correlations and the correlation matrix on the left side allows to see the single correlations between two selected images.
>The boxplot says "squared distance from the mean". Is it the mean of all
>the voxels for each brain voumes ?
Ups, couldn't find the term "squared distance from the mean" in that tool. Anyway, see my explanation above.
Best,
Christian
>
>Many thanks for your input,
>
>All the best
>
>Gabriel
>
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