The result of my attempts at prewhitening is a timeseries of volumes that are zero at every voxel. If I multiply my input data by some large number (i.e. 100), then some voxels in the prewhitened output are non-zero, but some voxels inside the brain are still zero at every timepoint. What am I missing here?
$ film_gls -rn stats -ac -sa -ms 5 -output_pwdata input.nii
Log directory is: stats
paradigm.getDesignMatrix().Nrows()=399
paradigm.getDesignMatrix().Ncols()=1
sizeTS=399
numTS=18507
Calculating residuals...
Completed
Estimating residual autocorrelation...
Calculating raw AutoCorrs... Completed
mode = 0.00391987
sig = 0
Spatially smoothing auto corr estimates
..................
Completed
Tukey M = 19
Tukey estimates... Completed
Completed
Prewhitening and Computing PEs...
Percentage done:
1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,Completed
Saving results...
Completed
$ fslstats stats/prewhitened_data.nii -r
0.000000 0.000000
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