if you have multiple variables then you have to do multiple regression before testing the correlation doug
On 02/21/2014 09:35 PM, charujing123 wrote: > Hi doug and others, > I want to perform correlation analysis,just one dependent variable and > one independent variable. Previously I think the contrast(i.e.0 0 0.5 > 0.5 0 0) I design is for correlation between score1 and thickness. But > yestoday I found this information > http://surfer.nmr.mgh.harvard.edu/fswiki/Fsgdf2G2V#Contrast6g1g2.age.mtx. > It told me that "Null Hypothesis: does mean of group age slope differ > from 0? Is there anaverage affect of age regressing out the effect of > group and weight?". Regressing out the effect of group and weight > represents this contrast is for multimple regression,not simple > correlation between two varibles. I am confused. > Doug, would you please tell me where I am wrong? > Thanks. > All the best. > Rujing Zha. > 2014-02-22 > ------------------------------------------------------------------------ > charujing123 > ------------------------------------------------------------------------ > *发件人：*Douglas Greve <gr...@nmr.mgh.harvard.edu> > *发送时间：*2014-02-21 23:35 > *主题：*Re: [Freesurfer] fsgdf and contrasts > *收件人：*"freesurfer"<freesurfer@nmr.mgh.harvard.edu> > *抄送：* > > I'm not sure I understand. Your contrasts below are fine. What are you > unsure about? > doug > > > > > On 2/20/14 7:48 PM, charujing123 wrote: >> Hidoug and others, >> Thanks doug. >> I see.If I want to implement multiple regression, i.e. two EVs(score1 >> and score2) explain pial thickness, what contrast I should design for >> this. >> Thanks again. >> All the best. >> Rujing Zha >> 2014-02-21 >> ------------------------------------------------------------------------ >> charujing123 >> ------------------------------------------------------------------------ >> *发件人：*Douglas N Greve <gr...@nmr.mgh.harvard.edu> >> *发送时间：*2014-02-21 03:39 >> *主题：*Re: [Freesurfer] fsgdf and contrasts >> *收件人：*"freesurfer"<freesurfer@nmr.mgh.harvard.edu> >> *抄送：* >> yes, they are, though you don't need to do the positive and negative >> contrasts because the sign is preserved >> doug >> On 02/20/2014 12:47 AM, charujing123 wrote: >> > Hi FS experts and users, >> > I am trying to implement independent sample t-test and correlation >> > analysis. >> > Here is my fsgdf design: >> > ----------------------------- >> > GroupDescriptorFile 1 >> > Title lh_ttest >> > Class CON_IA >> > Class PAT_IA >> > Variables score1 score2 >> > Input CON_IA01 CON_IA 0 0 >> > Input CON_IA03 CON_IA 0 0 >> > Input CON_IA05 CON_IA 0 0 >> > Input CON_IA06 CON_IA 0 0 >> > Input CON_IA07 CON_IA 3 7 >> > Input CON_IA09 CON_IA 0 0 >> > Input CON_IA14 CON_IA 0 0 >> > Input CON_IA15 CON_IA 0 0 >> > Input CON_IA16 CON_IA 7 12 >> > Input CON_IA19 CON_IA 6 15 >> > Input CON_IA24 CON_IA 6 11 >> > Input CON_IA27 CON_IA 3 3 >> > Input CON_IA32 CON_IA 7 21 >> > Input CON_IA33 CON_IA 7 21 >> > Input CON_IA35 CON_IA 0 0 >> > Input CON_IA38 CON_IA 7 15 >> > Input CON_IA39 CON_IA 2 3 >> > Input CON_IA40 CON_IA 6 8 >> > Input CON_IA41 CON_IA 2 4 >> > Input PAT_IA01 PAT_IA 8 13 >> > Input PAT_IA02 PAT_IA 9 38 >> > Input PAT_IA03 PAT_IA 9 33 >> > Input PAT_IA04 PAT_IA 9 27 >> > Input PAT_IA06 PAT_IA 9 26 >> > Input PAT_IA08 PAT_IA 8 16 >> > Input PAT_IA09 PAT_IA 9 33 >> > Input PAT_IA16 PAT_IA 9 35 >> > Input PAT_IA18 PAT_IA 9 39 >> > Input PAT_IA21 PAT_IA 9 32 >> > Input PAT_IA22 PAT_IA 9 31 >> > Input PAT_IA23 PAT_IA 9 35 >> > Input PAT_IA24 PAT_IA 9 40 >> > Input PAT_IA25 PAT_IA 9 29 >> > Input PAT_IA27 PAT_IA 9 30 >> > Input PAT_IA29 PAT_IA 9 30 >> > Input PAT_IA30 PAT_IA 8 32 >> > Input PAT_IA33 PAT_IA 9 13 >> > Input PAT_IA34 PAT_IA 9 21 >> > ------------------------------------------------ >> > Contrasts for independent sample t-test: >> > 1,CON_IA>PAT_IA:1 -1 0 0 0 0 >> > 2,PAT_IA>CON_IA:-1 1 0 0 0 0 >> > Contrasts for correlation analysis: >> > 1,possitive correlation analysis between pial thickness and score1:0 0 >> > 0.5 0.5 0 0 >> > 2,negtive correlation analysis between pial thickness and score1:0 0 >> > -0.5 -0.5 0 0 >> > 3,positive correlation analysis between pial thickness and score2:0 0 >> > 0 0 0.5 0.5 >> > 4,negtive correlation analysis between pial thickness and score2:0 0 0 >> > 0 -0.5 -0.5 >> > Are my designs appropriate? >> > If I want to implement regression analysis(i.e. dependent variable is >> > thickness and independent variables are score1 and score2), how to >> > design my contrast? >> > Thanks. >> > All the best. >> > Rujing Zha >> > 2014-02-20 >> > ------------------------------------------------------------------------ >> >> > charujing123 >> > >> > >> > _______________________________________________ >> > 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. >> >> >> _______________________________________________ >> 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
