Hi,
I am running a GM-BSS analysis and I would like to see whether there is a correlation between tensor/noddi scalar measurements (FA, ODI etc) and age.
head design.mat
/NumWaves 2
/NumPoints 38
/PPheights 1 1
/Matrix # intercept + age in days (not demeaned); b=0
1 160
1 185
1 167
...
head design.con
/NumWaves 2
/NumContrasts 2
/PPheights 1 1
/Matrix
0 -1
0 1
This is yet another question about the following randomised error msg:
randomise -i all_$input.nii.gz -o gbss_$input -m mask.nii.gz -d design.mat -t design.con -n 5000 --T2
Warning: All design columns have zero mean - consider using the -D option to demean your data
#### That shouldn't be the case considering the design mat & con ?
9.00819e+36 permutations required for exhaustive test of t-test 1
Doing 5000 random permutations
Starting permutation 1 (Unpermuted data)
Warning: The unpermuted statistic image for the current image contains no positive values, and cannot be processed with TFCE. A blank output image will be created.
As far as I can say there shouldn't be any issues with the 4D input image nor the design. What else could be causing this in a correlation?
Thank you in advance,
RD
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