问一道题：NO.PZ2015121802000038

问题如下：

The covariance of the market's returns with the stock's returns is 0.009. The standard deviation of the market's returns is 0.08, and the standard deviation of the stock's returns is 0.15. What is the correlation coefficient of the returns of the stock and the returns of the market?

选项：

0.75.

1.00.

1.75.

解释：

A is correct.

${\rho _{_{1,2}}} = \frac{{Co{v_{1,2}}}}{{{\sigma _1}{\sigma _2}}} = \frac{{0.009}}{{(0.08)(0.15)}} = 0.75$