Yes, that was an error. I was thinking of the case where X and Y are both normalised to have s.d. 1, in which case the regression line is indeed Y = cX, but that isn’t the case here. In general, the line is Y = bcX/a where the standard deviations of X and Y are a and b.
Yes, that was an error. I was thinking of the case where X and Y are both normalised to have s.d. 1, in which case the regression line is indeed Y = cX, but that isn’t the case here. In general, the line is Y = bcX/a where the standard deviations of X and Y are a and b.