Hi freesurfer community,

I am trying to do QDEC with a data for 2 groups but stuck in this error for many hours now. Tried and checked everything I could think of. Also went through the old threads and checked those recommneded but still could not solve it. Your hint will be very helpful.

ERROR: matrix is ill-conditioned or badly scaled, condno = 18696.1

--------------------------------

Possible problem with experimental design:

Check for duplicate entries and/or lack of range of

continuous variables within a class.

If you seek help with this problem, make sure to send:

1. Your command line:

mri_glmfit --y /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled/y.mgh --fsgd /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled/qdec.fsgd dods --glmdir /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled --surf fsaverage lh --label /gpfs/fs1/home/mmuthura/freesurfer/subjects/fsaverage/label/lh.aparc.label --C /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled/contrasts/lh-Avg-Intercept-thickness.mat --C /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled/contrasts/lh-Diff-f-m-Intercept-thickness.mat --C /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled/contrasts/lh-Diff-Epi-Chr-Intercept-thickness.mat --C /gpfs/fs1/home/mmuthura/freesurfer/subjects/qdec/Untitled/contrasts/lh-X-gender-Group-Intercept-thickness.mat

2. The FSGD file (attached)

3. Design Matrix

Design matrix ------------------

1.000 0.000 0.000 0.000 31.300 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 22.760 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 29.390 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 49.160 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 23.810 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 45.000 0.000 0.000 0.000;

0.000 1.000 0.000 0.000 0.000 21.830 0.000 0.000;

1.000 0.000 0.000 0.000 49.540 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 40.550 0.000 0.000 0.000;

0.000 1.000 0.000 0.000 0.000 22.660 0.000 0.000;

1.000 0.000 0.000 0.000 26.080 0.000 0.000 0.000;

0.000 1.000 0.000 0.000 0.000 32.570 0.000 0.000;

0.000 1.000 0.000 0.000 0.000 47.190 0.000 0.000;

1.000 0.000 0.000 0.000 27.710 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 25.860 0.000 0.000 0.000;

1.000 0.000 0.000 0.000 25.180 0.000 0.000 0.000;

0.000 0.000 1.000 0.000 0.000 0.000 27.630 0.000;

0.000 0.000 1.000 0.000 0.000 0.000 51.930 0.000;

0.000 0.000 1.000 0.000 0.000 0.000 25.060 0.000;

0.000 0.000 0.000 1.000 0.000 0.000 0.000 60.650;

0.000 0.000 1.000 0.000 0.000 0.000 59.360 0.000;

0.000 0.000 0.000 1.000 0.000 0.000 0.000 62.450;

0.000 0.000 1.000 0.000 0.000 0.000 20.480 0.000;

0.000 0.000 1.000 0.000 0.000 0.000 36.550 0.000;

0.000 0.000 1.000 0.000 0.000 0.000 37.000 0.000;