Hi Jack - if you run tsplot with the "-m mask" option and the -n tsplot
option and are not doing any other thresholding then yes the timeseries
data should be the same.....
Cheers, Steve.
On Mon, 10 Oct 2005, Jack Grinband wrote:
> Hi Steve,
> So, by default, all the stats in featquery are calculated using a binary mask but all the plots are
> calculated using a weighted mask. Is this right?
>
> I ran tsplot using -n, but I'm still getting different values for "data", "full model fit", and the
> residuals across EVs. It seems to me that none of these should change. Is there a reason why
> they're different?
> thanks,
>
> jack
>
>
> >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
>
--
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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