Hello,<br><br>I am trying to covary for Gender in mri_glmfit, but I am having errors pop up.  I tried to follow Doug&#39;s suggesting in this post:<br><a href="http://www.mail-archive.com/freesurfer@nmr.mgh.harvard.edu/msg12272.html">http://www.mail-archive.com/freesurfer@nmr.mgh.harvard.edu/msg12272.html</a><br>

but after modifying my Xg.dat file and rerunning mri_glmfit, it says:<br>ERROR: matrix is ill-conditioned or badly scaled, condno = 1.53319e+07<br><br>I can run it using the --illcond flag, but then I get a bunch of:<br>
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CEPHES ERROR: fdtrc domain error<br>***<br><br>Can anyone please give advice on how to covary for Gender in mri_glmfit (or qdec)?<br><br>As always, thank you for all of your great help!!<br>Jeff Sadino<br>