Adam,
this is covered in the FAQ, see
http://www.fmrib.ox.ac.uk/fslfaq/#feat_rank for details. In order to
give more specific advice we'd need to know details of your design -
the feat directory should have design.mat and design.gif in it, maybe
you want to post those?
cheers
christian
On 11 Oct 2004, at 01:56, Adam Gries wrote:
> Hello,
> 1) I've been trying to run a lower level analysis for a large number of
> contrasts in different combinations and have received the following
> message:
>
> At least one EV is (close to) a linear combination of the others. You
> should probably alter your design. (Design matrix is rank deficient -
> ratio of min:max eigenvalues in SVD of matrix is 0.000000e+00)
>
> 2) I could technically run the analysis later but received no results.
> 3) The EV's are expected to have very different values and I do not
> understand how one could be a combination of another.
>
> Any explanation and help would be appreciated,
>
> Thanx,
>
> Adam Gries
>
>
--
Christian F. Beckmann
Oxford University Centre for Functional
Magnetic Resonance Imaging of the Brain,
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
Email: [log in to unmask] - http://www.fmrib.ox.ac.uk/~beckmann/
Phone: +44(0)1865 222782 Fax: +44(0)1865 222717
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