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Thank you so much for your reply Steve And as I will do between group comparisons and no *paired* (I guess I dind't wrote it clearly in the past) I won't add the EV per subject to model out the subject means. Bests El 25/11/10, Stephen Smith <[log in to unmask]> escribió: > > > > Hi > > > > > On 24 Nov 2010, at 10:14, Gabriel Gonzalez Escamilla wrote: > > > > > Thanks Stephen > > > > just to be sure, I've run a one-way ANOVA for this design with 3 contrasts and one F: > > c1: 1 0 0 [and zeros for covs] > > c2: 0 1 0 [and zeros for covs] > > c3: 0 0 1 [and zeros for covs] > > and F: 1 1 1 > > > > > > I think this is ok - though also see the example at > http://fsl.fmrib.ox.ac.uk/fsl/feat5/detail.html#ANOVA1factor4levels (http://fsl.fmrib.ox.ac.uk/fsl/feat5/detail.html#ANOVA1factor4levels) > > > > > > is it correct? for meassuring any difference on the 3 groups??? > > and if a would perform paired differences, would be: > > 1 -1 0 [and zeros for covs] > > 1 0 -1 [and zeros for covs] > > 0 1 -1 [and zeros for covs] > > > > > > > > Sure - though if you really mean *paired* differences then presumably you also need one EV per subject to model out the subject means - again see the various FEAT examples…. > > > Cheers. > > > > > > > > > > > > > El 24/11/10, Stephen Smith <[log in to unmask] <[log in to unmask]>> escribió: > > > > > > > > > > > > > > > Hi - in general you should demean the additional covariates, including the sex. > > > > > > Cheers. > > > > > > > > > > > > > > > > > > On 23 Nov 2010, at 15:44, Gabriel Gonzalez Escamilla wrote: > > > > > > > > > > > > > > > I've introduce a regressor of no interest de-meaned but i have another one the sex wich has not been de-meaned > > > > > > > > > > > > > > > > Group EV1 EV2 EV3 EV4 EV5 EV6 EV7 EV8 EV9 > > > > > > > > > > > > 1 1 0 0 1.5 0 0 1 0 0 > > > > > > > > > > > > 1 1 0 0 -6.4 0 0 1 0 0 > > > > > > > > > > > > 1 1 0 0 2.8 0 0 2 0 0 > > > > > > > > > > > > 1 1 0 0 -6.4 0 0 2 0 0 > > > > > > > > > > > > 2 0 1 0 0 1.4 0 0 2 0 > > > > > > > > > > > > 2 0 1 0 0 1.3 0 0 1 0 > > > > > > > > > > > > 2 0 1 0 0 -1.7 0 0 1 0 > > > > > > > > > > > > 2 0 1 0 0 1.4 0 0 2 0 > > > > > > > > > > > > 3 0 0 1 0 0 -6.4 0 0 1 > > > > > > > > > > > > 3 0 0 1 0 0 1.2 0 0 2 > > > > > > > > > > > > 3 0 0 1 0 0 -1.6 0 0 1 > > > > > > > > > > > > 3 0 0 1 0 0 -2.4 0 0 2 > > > > > > > > > > > > > > > > > > > > This is an example of the design matrix, I have 3 groups and I'd insert the age(z-scored) and sex per group. > > > > > > > > Bests > > > > Gabriel > > > > > > > > > > > > > > > > > > > > > > > > > > > > El 23/11/10, David Flitney <[log in to unmask] <[log in to unmask]>> escribió: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Hi > > > > > > > > > > > > > > > > > > > > This means that one, or more, of your regressors are already modelling the mean. Please check and if you're in any doubt then post your design so we can double check it. > > > > > > > > > > > > > > > Dave > > > > > > > > > > > > > > > > > > > > On 23 Nov 2010, at 12:02, Gabriel Gonzalez Escamilla wrote: > > > > > > > > > > > > > > > > > > > > > > > Dear FSL users > > > > > > > > > > > > > > > > > > I'm running randomise, and when i add the -D flag warning message appears: > > > > > > > > > > > > > > > > > > > > > > > > "Warning: You have demeaned your data, but at least one design column has non-zero mean" > > > > > > > > > > > > > > > > > > > > > > > > Does this message tells me that is something wrong in my design, or it just appears? > > > > > > > > > > > > > > > > > > > > > > > > Regards > > > > > > > > > > > > Gabriel > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > Dave Flitney, IT Manager > > > > > Oxford Centre for Functional MRI of the Brain > > > > > E:[log in to unmask] <[log in to unmask]> W:+44-1865-222713 F:+44-1865-222717 > > > > > URL: http://www.fmrib.ox.ac.uk/~flitney (http://www.fmrib.ox.ac.uk/%7Eflitney) > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > Gabriel González Escamilla > > > > Laboratory of Functional Neuroscience > > > > Department of Physiology, Anatomy, and Cell Biology > > > > University Pablo de Olavide > > > > Ctra. de Utrera, Km.1 > > > > 41013 - Sevilla > > > > - Spain - > > > > > > > > Email: [log in to unmask] <[log in to unmask]> > > > > http://www.upo.es/neuroaging/es/ (http://www.upo.es/neuroaging/es/) > > > > > > > > > > > > > > > --------------------------------------------------------------------------- > > > Stephen M. Smith, Professor of Biomedical Engineering > > > Associate Director, Oxford University FMRIB Centre > > > > > > FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK > > > +44 (0) 1865 222726 (fax 222717) > > > [log in to unmask] <[log in to unmask]> http://www.fmrib.ox.ac.uk/~steve (http://www.fmrib.ox.ac.uk/%7Esteve) > > > --------------------------------------------------------------------------- > > > > > > > > > > > > > > > > > > > -- > > Gabriel González Escamilla > > Laboratory of Functional Neuroscience > > Department of Physiology, Anatomy, and Cell Biology > > University Pablo de Olavide > > Ctra. de Utrera, Km.1 > > 41013 - Sevilla > > - Spain - > > > > Email: [log in to unmask] <[log in to unmask]> > > http://www.upo.es/neuroaging/es/ (http://www.upo.es/neuroaging/es/) > > > > > --------------------------------------------------------------------------- > Stephen M. Smith, Professor of Biomedical Engineering > Associate Director, Oxford University FMRIB Centre > > FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK > +44 (0) 1865 222726 (fax 222717) > [log in to unmask] <[log in to unmask]> http://www.fmrib.ox.ac.uk/~steve (http://www.fmrib.ox.ac.uk/%7Esteve) > --------------------------------------------------------------------------- > > > > > -- Gabriel González Escamilla Laboratory of Functional Neuroscience Department of Physiology, Anatomy, and Cell Biology University Pablo de Olavide Ctra. de Utrera, Km.1 41013 - Sevilla - Spain - Email: [log in to unmask] http://www.upo.es/neuroaging/es/