Thank you all. I don't see a comment on correction for temporal autocorrelation in the PTN document though. Could someone please point me to a page where this is explained?
Thanks, Cherry On Mon, Mar 30, 2015 at 12:18 PM, Stephen Smith <[email protected]> wrote: > yup - that also affects the scaling - see FSLNets doc and the PTN release > doc. > Cheers. > > > On 30 Mar 2015, at 18:17, Glasser, Matthew <[email protected]> > wrote: > > Hi Steve, > > What about the correction for temporal autocorrelation? > > Matt. > > From: Stephen Smith <[email protected]> > Date: Monday, March 30, 2015 at 12:15 PM > To: Yizhou Ma <[email protected]> > Cc: "[email protected]" <[email protected]> > Subject: Re: [HCP-Users] netmats in HCP > > Hi - one thing is that we estimate (z versions of) netmats separately > for each 15min run and then average the 4 netmats to give a single netmat > per subject. > Cheers. > > > On 30 Mar 2015, at 18:14, Yizhou Ma <[email protected]> wrote: > > Hi Timothy, > > Thank you for pointing that out. I typed that wrong but I used the > correct transformation in matlab. As I said my transformed z scores are > actually almost perfectly linearly correlated with HCP netmats, though the > latter is much larger. I want to understand why the latter is larger and > why the two are not exactly correlated. > > Thanks, > Cherry > > On Mon, Mar 30, 2015 at 12:08 PM, Timothy Coalson <[email protected]> wrote: > >> A quick possibility: if you have pasted in the formula you used, I see an >> order of operations problem: .5*ln(1+r)-ln(1-r) means (.5*ln(1+r))-ln(1-r), >> where the usual formula is .5*ln((1+r)/(1-r)), which after some log >> identities becomes .5*(ln(1+r)-ln(1-r)). >> >> Tim >> >> >> On Mon, Mar 30, 2015 at 11:02 AM, Yizhou Ma <[email protected]> wrote: >> >>> Dear HCP experts, >>> >>> I am trying to reproduce the individual netmats from HCP500-PTN so >>> that I am sure where the numbers come from. I used individual node >>> timeseries in /ts2/subjID and did correlation in matlab. I then used >>> fisher's z transformation: .5*ln(1+r)-ln(1-r). The resulting netmat is >>> different from what is provided in *_netmat1/. However, they almost have a >>> linear relationship. It seems to me that HCP is not using the same z >>> transformation I have used. The transformation seems more like >>> 7*ln(1+r)-ln(1-r). >>> >>> I have downloaded FSLNets but could not identify which function was >>> used to generate individual netmats in the first place. The example script >>> seems to be about group-level netmats only. >>> >>> Could you please share with me how exactly the numbers in individual >>> netmats were generated? >>> >>> Thanks, >>> Cherry >>> _______________________________________________ >>> HCP-Users mailing list >>> [email protected] >>> http://lists.humanconnectome.org/mailman/listinfo/hcp-users >>> >> >> > _______________________________________________ > HCP-Users mailing list > [email protected] > http://lists.humanconnectome.org/mailman/listinfo/hcp-users > > > > --------------------------------------------------------------------------- > 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) > [email protected] http://www.fmrib.ox.ac.uk/~steve > --------------------------------------------------------------------------- > > Stop the cultural destruction of Tibet <http://smithinks.net/> > > > > > _______________________________________________ > HCP-Users mailing list > [email protected] > http://lists.humanconnectome.org/mailman/listinfo/hcp-users > > > ------------------------------ > The materials in this message are private and may contain Protected > Healthcare Information or other information of a sensitive nature. If you > are not the intended recipient, be advised that any unauthorized use, > disclosure, copying or the taking of any action in reliance on the contents > of this information is strictly prohibited. If you have received this email > in error, please immediately notify the sender via telephone or return mail. > > > > --------------------------------------------------------------------------- > 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) > [email protected] http://www.fmrib.ox.ac.uk/~steve > --------------------------------------------------------------------------- > > Stop the cultural destruction of Tibet <http://smithinks.net> > > > > > _______________________________________________ HCP-Users mailing list [email protected] http://lists.humanconnectome.org/mailman/listinfo/hcp-users
