That is the correct matrix to use. You can create a new FSGD file (and the second matrix would be correct for it), but you do not have to. It will save you a few degrees of freedom. doug
On 09/07/2012 05:49 AM, Meng Li wrote: > Hi professor, > Thanks for your reply. > When I perform the main effect of dignosis, is the following matrix I > used correct? > 0.25 0.25 0.25 0.25 -0.25 -0.25 -0.25 -0.25 0 0 0 0 0 0 0 0 0 0 0 0 0 > 0 0 0 (I think it regressed out the effect of genotype and gender, > that is it takes the genotype as a covariable) > > Or I should create another fsgd file, that has 4 classes: AF, AM, BF, > BM. And I can use the matrix (0.5 0.5 -0.5 -0.5 0 0 0 0 0 0 0 0) to > perform the main effect of diagnosis. > Which one of two mentioned matrix is right? > Thanks a lot. > Best wishes > Meng > > -- Douglas N. Greve, Ph.D. MGH-NMR Center gr...@nmr.mgh.harvard.edu Phone Number: 617-724-2358 Fax: 617-726-7422 Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.