<Li> Related to the bivariate ellipses of isoconcentration </Li> <Li> Function of test statistics from designed experiments </Li> <Li> Ratio of two means </Li> <P> For uncentered data, there is a relation between the correlation coefficient and the angle φ between the two regression lines, y = g (x) and x = g (y), obtained by regressing y on x and x on y respectively . (Here φ is measured counterclockwise within the first quadrant formed around the lines' intersection point if r> 0, or counterclockwise from the fourth to the second quadrant if r <0 .) One can show that if the standard deviations are equal, then r = sec φ − tan φ, where sec and tan are trigonometric functions . </P>

How do you find the pearson correlation coefficient