yes On 06/03/2013 02:26 PM, Fotiadis, Panagiotis wrote: > I see. Would it be correct to say that better kurtosis would be illustrated > as less significant clusters in the kurtosis.mgh overlay? > > Panos > ________________________________________ > From: freesurfer-boun...@nmr.mgh.harvard.edu > [freesurfer-boun...@nmr.mgh.harvard.edu] on behalf of Douglas N Greve > [gr...@nmr.mgh.harvard.edu] > Sent: Monday, June 03, 2013 1:53 PM > To: freesurfer@nmr.mgh.harvard.edu > Subject: Re: [Freesurfer] Group Analysis Question > > Not necessarily. It could have been in the FS analysis. You can run > mri_glmfit with --kurtosis (a hidden option). This will create a > kurtosis.mgh and pkurtosis.mgh. Kurtosis is a measure of gaussianity of > the residuals (larger being less gaussian). The pkurtosis the the sig > (-log10(p)) of the probability of seeing the kurtosis under the null > (ie, the residuals are gaussian). So you can see if one model gives you > better kurtosis than another. > > doug > > > On 06/03/2013 01:20 PM, Fotiadis, Panagiotis wrote: >> I see. Yes from the one hand the results that I got make a lot more sense in >> the second type of analysis, compared to the first one, however, there are >> some somewhat important difference between the two analyses. If there is an >> issue with the data, do you believe that it would be in the acquisition? >> Because I checked the reconstructions and they look fine. >> >> Thanks, >> Panos >> ________________________________________ >> From: freesurfer-boun...@nmr.mgh.harvard.edu >> [freesurfer-boun...@nmr.mgh.harvard.edu] on behalf of Douglas Greve >> [gr...@nmr.mgh.harvard.edu] >> Sent: Monday, June 03, 2013 11:24 AM >> To: freesurfer@nmr.mgh.harvard.edu >> Subject: Re: [Freesurfer] Group Analysis Question >> >> I would not expect them to be identical but similar. If they change a >> lot there may be an issue with your data. >> doug >> >> >> >> On 6/3/13 11:11 AM, Fotiadis, Panagiotis wrote: >>> Hey Doug, >>> >>> I have run a group analysis on my data with two different ways. (The input >>> is cortical thickness.) In the first analysis, I specified 4 groups >>> (Diseased_Male, Diseased_Female, Healthy_Male, and Healthy_Female) whereas >>> in the second, just two groups (Diseased, Healthy). One of the comparisons >>> that I did was the age slope between Diseased and Healthy. Therefore in the >>> first analysis, I set the contrast vector to be [0 0 0 0 0.5 0.5 -0.5 -0.5] >>> and in the second analysis I set it to [0 0 1 -1]. However, the results >>> that came up were somewhat different. For instance there were clusters in >>> the second analysis that were significant but were not significant in the >>> first analysis. >>> Shouldn't the results be the same? >>> >>> Thank you, >>> Panos >>> _______________________________________________ >>> 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 >> >> _______________________________________________ >> 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 > > _______________________________________________ > 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.
