The sample standard deviations for x and y are 10 and 15, respectively. The covariance between x and y is −120. The correlation coefficient between x and y is ________.
A) −0.8
B) −0.5
C) 0.5
D) 0.8

Question

Quizplus · Accepted Answer

The correlation coefficient is calculated as the covariance between x and y divided by the product of their standard deviations. Thus, correlation coefficient = −120 / (10*15) = −120 / 150 = −0.8.

The Sample Standard Deviations for X and Y Are 10