Dear SPMers,
I would like to find out if it's possible to calculate some version of
percent signal change based on change in the 1st eigenvariate of an ROI,
e.g. Y = ((Y - mean(Y))./mean(Y))*100;
Also, the VOI timecourse that SPM outputs is on the course of 150-200
(units??), while the adjusted and fitted responses that the plot
function gives are on a much smaller scale. How is this data different
from the scaled data and is the 1st eigenvariate a good indicator of
signal changes maintaining the structure of the raw variance in the data?
Thank you for your help.
Mike
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