gamma and pcc should be the same sign. The relationship to the sign of beta depends on your contrast. If beta is negative and your contrast element is negative, then you will get a positive gamma and pcc.
On 09/13/2018 02:15 PM, Nicola Toschi wrote: > External Email - Use Caution > Thank you Doug, > > that was exactly the question... > > it may be a trivial one but I have been messing aroung with several > effects size calculation for a while and just wanted to make sure. So > negative contrast (-1), negative beta.mgh, positive (?) gamma.mgh, and > negative pcc.mgh withing the same significant cluster? > > Thanks!!! > > nicola > > > > On 09/13/2018 07:39 PM, Douglas N. Greve wrote: >> not sure what your question is. The pcc should have the same sign as the >> contrast. >> >> On 09/13/2018 12:20 PM, Nicola Toschi wrote: >>> External Email - Use Caution >>> >>> Hi List, >>> >>> a dimple question about using partial correlation (pcc.mgh) as effect >>> size measure. I am running multivariate regression and setting positive >>> and negative contrasts one variable at a time, e.g. a design matrix >>> with >>> columns like >>> >>> Intercept Age Gender Fact1 Fact2 .... >>> >>> and a bunch of contrasts like >>> >>> 0 0 0 1 0 >>> >>> 0 0 0 -1 0 >>> >>> Now let's say the second contrast gives me a significant results after >>> MC correction in a certain cluster, what sign should i expect in PCC in >>> that cluster (on average)? >>> >>> Thank you very much in advance, >>> >>> Nicola >>> >>> >>> _______________________________________________ >>> 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. >> > _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
