Try normalizing your continuous variables (ie, subtract the mean and divide by the stddev)

On 07/28/2016 06:06 AM, Mahtab Farahbakhsh wrote:

Dear FreeSurfer,

I am trying to compare my subjects to the healthy group, but when I put the matrix into qdec, I get the following error:

Normalized matrix condition is 1e+08 Design matrix ------------------ 1.000 0.000 0.000 0.000 68.000 0.000 0.000 0.000; 0.000 0.000 1.000 0.000 0.000 0.000 66.000 0.000; 1.000 0.000 0.000 0.000 40.000 0.000 0.000 0.000; 0.000 0.000 1.000 0.000 0.000 0.000 35.000 0.000; 1.000 0.000 0.000 0.000 72.000 0.000 0.000 0.000; 0.000 0.000 1.000 0.000 0.000 0.000 71.000 0.000; 1.000 0.000 0.000 0.000 22.000 0.000 0.000 0.000; 0.000 0.000 1.000 0.000 0.000 0.000 22.000 0.000; 0.000 1.000 0.000 0.000 0.000 20.000 0.000 0.000; 0.000 0.000 0.000 1.000 0.000 0.000 0.000 20.000;

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ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08

1. Your command line:

mri_glmfit --y 

/Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/y.mgh --fsgd /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/qdec.fsgd dods --glmdir /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled --surf fsaverage lh --label /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/fsaverage/label/lh.aparc.label --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-Avg-Intercept-thickness.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-Avg-thickness-age-Cor.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-Diff-Male-Female-Intercept-thickness.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-Diff-Male-Female-Cor-thickness-age.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-Diff-spelling-healthy-Intercept-thickness.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-Diff-spelling-healthy-Cor-thickness-age.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-X-gender2-diagnosis_spelling-Intercept-thickness.mat --C /Applications/freesurfer/experimental_data/FAM_TG/DICOM_DATA/qdec/Untitled/contrasts/lh-X-gender2-diagnosis_spelling-Cor-thickness-age.mat

the table file is also attached to the mail.

Would you please kindly guide me with this?

Best Regards, Mahtab.

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