Question

The equations of the two lines of regression are 6x + y − 31 = 0 and 3x + 2y – 26 = 0. Find the value of the correlation coefficient

Answer 1

r = ${\displaystyle \pm \sqrt{{\text{b}}_{xy}\cdot {\text{b}}_{yx}}}$

= ${\displaystyle \pm \sqrt{\frac{-1}{6}\times \frac{-3}{2}}}$

= ${\displaystyle \pm \frac{1}{2}}$

= ${\displaystyle \pm 0.5}$

Since the values of b_xy and b_yx are negative,

r is also negative.

∴ r = – 0.5