We get these kind of reports occasionally. When I ask people to confirm that they use exactly the same design matrix in SPSS, I never hear back, so I assume that it gets resolved. So please check. The other thing you can do is to run in matlab, something like
cd glmdir/contrast X = load('Xg.dat'); y = load('ocn.dat'); C = load('C.dat'); [beta rvar] = fast_glmfit(y,X); [F p] = fast_fratio(beta,X,rvar,C); p will be the p-value If you used an unsigned cluster-forming threshold (ie, abs), then it is possible that some of the voxels are pos and some are neg so that they average out doug On 01/26/2015 09:03 AM, maaike rive wrote: > Dear Freesurfer experts, > > Sorry to bother you again, but I have two more questions about > extracting (thickness/surface/GI) values from a certain cluster. > > As I understood, the abs.y.ocn.dat file gives the average values for a > given significant cluster (e.g. a cluster where there is a significant > AxB interaction). > > I may be completely misunderstanding things, but if I use these values > in SPSS for further statistics and test the same interaction (AxB), > than according to SPSS this interaction is /not /significant > (corrected for the same covariates as in the FSGD file). > > Could you tell me what is going wrong here? I do not trust my results now. > > Furthermore, is it possible (and if so, how?) to extract the average > values of exactly the same cluster, but in an independent group not > used in the analysis, for post-hoc comparisons in SPSS? > > Thanks, > > Maaike > > > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer -- 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: https://gate.nmr.mgh.harvard.edu/filedrop2 www.nmr.mgh.harvard.edu/facility/filedrop/index.html Outgoing: ftp://surfer.nmr.mgh.harvard.edu/transfer/outgoing/flat/greve/ _______________________________________________ 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.