Hi Mahnida, it is not using permutation. Rather, it synthesizes white Gaussian noise on the surface, smooths it, then clusters. This does not need your data, so this can be precomputed. doug
On 04/12/2012 08:53 PM, Mahinda Yogarajah wrote:
Dear Experts,
I wonder whether someone could explain to me how the monte-carlo correction in qdec manages to be instantaneous. I appreciate it uses pre-computed data, but I am a little confused. I thought that this sort of permutation based method is based on relabelling of one's own specific dataset, and therefore do not understand how precomputed data is used.
Thanks for the help.
Mahinda
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer