It really is just a matter of justifying and explaining your chosen statistical model. If you believe that two groups have the same regression slope for a parameter (but possibly different offsets/intercepts), then you would use a "DOSS" model -- this is akin to a model in SPSS/SAS in which you model a main effect of group and a single (main) effect of the regressor that applies to all subjects (e.g., Y = group age). If you believe that the two groups might possibly have a different slope, then you would use a "DODS" model (also known as a heterogeneous slopes model) -- this is equivalent to a model in SPSS/SAS in which you model a main effect of group (different offsets/intercepts) and separate (heterogeneous) slopes for the two groups i.e,. you model a possible interaction between group and slope; Y = group age group*age).
cheers, -MH On Tue, 2011-02-01 at 20:49 +0100, Christian Scheel wrote: > Dear all, > > does anyone know one or two good method papers to cite when describing > the difference of DOSS and DODS? I have already screened Pubmed and Co. > but did not really find anything convincing. > > Any help greatly appreciated! > > Best wishes, > Christian Scheel > > _______________________________________________ > 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
