Dear FSL Experts,
I am trying to create a quadratic intensity regressor. I am doing this by having three ev's, modeled thusly:
EV1) on/off
EV2) linear intensity (intensity-mean intensity)
EV3) (EV2)^2
In the FSL manual it looks like they did this as follows
EV1)on/off
EV2) linear intensity (intensity-mean intensity)
EV3) ((EV2)^2-(Average of EV2^2))*-1
Any idea why it is done this way and how I should best model this regressor?
Thanks,
Noam
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