Question

If both the regression lines intersect perpendicularly, then

• A. $r<-1$
• B. $r=1$
• C. $r=0$
• D. $r=\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.$

Answer 1

The correct option is C

$r=0$

Explanation for the correct option:

If the correlation coefficient ${\mathit{r}}_{\mathit{x}\mathit{y}}\mathit{=}\mathit{0}\mathit{,}$then the two regression lines are perpendicular to each other.

Hence $\mathit{r}\mathbf{=}\mathbf{0}$ (by using properties of regression).

Hence option(C) is correct.