Hello All,
I am trying to calculate the adjusted coefficient of multiple
determination (Rsq) for the fMRI data I am working with. In order to
do that, I need the residual sum-of-squares and the total
sum-of-squares for the fMRI data. The residual sum-of-squares
calculations are already provided in the ResMS image files that I am
fully aware of. The data in these image files are float64 (double
precision). The input image files are in int16 precision, so
calculating the total sum-of-squares is fruitless because the residuals
are in double precision. So this means the calculation of the
residuals themselves is not simply just subtracting the measured pixel
intensity (in the original images) from the estimated pixel intensity
from the design matrix. I need to get the format (or units) of the
residual sum-of-squares and total sum-of-squares to agree so that I may
calculate Rsq.
Any suggestions?
Thank you.
Todd Penney
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