you can select age, IQ and mean thickness as 'nuisance' variables, and then your group can be the main discrete variable.
as for mean thickness causing a failure, it it probably the case that the values are too close to each other. treating mean thickness as a covariate is probably not necessary anyway. n. On Tue, 2011-09-20 at 16:23 -0600, Dalwani, Manish wrote: > Hello Freesurfer’s, > > I am using QDEC and I have created and FSGD descriptor file with 2 > groups (pts and ctrls) and three continuous variables: age, IQ and > mean thickness. I have 2 questions: > > 1. I can only choose 2 covariates at one time? How can I choose > all three covariates in one model in my design? > 2. I tried group and 2 covariates combinations to check if it > runs ok and found that when I select age and IQ, it > runs...when I select IQ and mean thickness it runs but it > fails when I try running with age and mean thickness in the > model? The error in the terminal says matrix not correct, > check duplicates..., etc.. > > What I am doing wrong? > > Thanks, > Manish Dalwani > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer _______________________________________________ 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.
