> if i wanted the overall effect regardless of video, should i input all 3 values or take the mean after r-to-z
> transformation and use that as input (i.e. rInput = (rA+rB+rC)/3) ?
That seems reasonable to me.
> if I wanted a contrast of condition X > condition Y where rA and rB belong to conditon X and rC belondgs
> to condition Y, would it be correct to do (rA+rB)/2) - rC and use the resulting value as input.
I'm not familiar with the context. If you believe that (rA+rB)/2) represents condition X just as rC does condition Y, then your suggestion may be OK.
Gang