Ah - I see. When you use a mask in Featquery it passes that onto tsplot
such that this replaces the use of FEAT cluster masks in masking voxels
for averaging timeseries (etc) over. However this is separate in tsplot
from whether this averaging is weighted by the raw zstat images, which
still happens. If you want to also stop tsplot from weighting the
timeseries averaging with the zstats then insert the "-n" option in to the
featquery script at the appropriate place.
Hope this makes sense! Cheers, Steve.
On Sat, 1 Oct 2005, Jack Grinband wrote:
> Hi Steve,
> I'm still confused:
> 1. So by default, featquery binarises the mask and since it's already binarised, tsplot doesn't need
> the -n option?
>
> 2. Shouldn't the partial model fit and reduced data data be different if you turn the binarise option
> on and off in featquery? In my case tsplot_zstat1.txt is identical in the two cases.
>
> 3. Back to my original question: if the mask is binarised, shouldn't "data" and "full model fit" be
> identical across EVs?
> thanks,
>
> jack
>
>
>
> >Hi - that's right - in featquery the mask weighting option determines
> >whether the featquery mask is binarised or not _before_ passing this into
> >tsplot with the -m options - hence the tsplot -n option isn't needed.
> >
> >Cheers, Steve.
> >
> >
> >
> >On Sat, 1 Oct 2005, Jack Grinband wrote:
> >
> >> After looking at the log file, it appears to me that the "Do not binarise mask (allow weighting)"
> >> button, doesn't actually add the -n option. Is this correct?
> >>
> >> jack
> >>
> >>
> >>
> >> On Sat, 1 Oct 2005 04:54:50 +0100, Jack Grinband <[log in to unmask]> wrote:
> >>
> >> >Hi All,
> >> >I'm a bit confused by the definition of "data" and "full model fit" in the tsplot output. If I have
> a
> >> >model with several EVs, I would expect that "data" for EV1 should be the same as "data" for
> EV2
> >> >(that is, data averaged across all voxels within an ROI). Similarly, I would expect the "full
> model
> >> >fits" to be the same for the two EVs. But I get different values for "data" even though I have
> "Do
> >> >not binarise mask" turned off. What am I missing?
> >> >thanks,
> >> >
> >> >jack
> >>
> >
> >--
> > Stephen M. Smith DPhil
> > Associate Director, FMRIB and Analysis Research Coordinator
> >
> > Oxford University Centre for Functional MRI of the Brain
> > John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
> > +44 (0) 1865 222726 (fax 222717)
> >
> > [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
> >===========================================================
> ==============
>
--
Stephen M. Smith DPhil
Associate Director, FMRIB and Analysis Research Coordinator
Oxford University Centre for Functional MRI of the Brain
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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