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Hi Vladimir, this makes sense, thanks so much for clearing it up. Best, Jane On Thu, Aug 27, 2015 at 4:54 AM, Vladimir Litvak <[log in to unmask]> wrote: > According to Gareth, EBB also has a tendency to at least bias the > locations to be the same across conditions so it's not unreasonable. > > Vladimir > > On Wed, Aug 26, 2015 at 6:27 PM, Jane Kouptsova <[log in to unmask]> > wrote: > >> Vladimir, thank you for your quick response. I am using EBB - is this >> assumption also true here, or would my results be unusual for this >> algorithm? >> >> Thanks, >> Jane >> >> On Wed, Aug 26, 2015 at 12:29 PM, Vladimir Litvak < >> [log in to unmask]> wrote: >> >>> Dear Jane, >>> >>> If you are using the MSP method (GS or ARD options) running it on the >>> three conditions combined this makes a lot of sense as this method assumes >>> that the same sources are active in all the conditions, just their level of >>> activation differs. So the algorithm will try to find sources that can fit >>> all the three conditions. If you select e.g. the 'IID' option, this should >>> not be the case. >>> >>> Best, >>> >>> Vladimir >>> >>> On Wed, Aug 26, 2015 at 3:47 PM, Jane Kouptsova <[log in to unmask]> >>> wrote: >>> >>>> Dear all, >>>> I am running an MEG analysis using SPM12, where I look at differences >>>> between three conditions, say 1, 2 and 3. When I run contrasts, I expect >>>> 3vs1 and 3vs2 to give similar results, and this is what I'm getting, >>>> however, more than being similar, many of the cluster peak coordinates are >>>> identical. Is this a cause for concern? >>>> >>>> The Z, D-uncorr and other values from the contrast are slightly >>>> different even when peaks are identical, and running a 1vs2 contrast also >>>> gives some results. So I know I didn't accidentally assign the same set of >>>> trials to both conditions. Is there anything else I should check to be sure >>>> of the output? >>>> >>>> Many thanks, >>>> Jane >>>> >>> >>> >> >