NO.PZ2016062402000002
问题如下：
Which one of the following statements about the correlation coefficient is false?
选项： It
always ranges from -1 to +1.
A correlation coefficient of zero means that two random variables are independent.
C.It is a measure of linear relationship between two random variables.
D.It can be calculated by scaling the covariance between two random variables.
解释：
Correlation is a measure of linear association. Independence implies zero correlation, but the reverse is not always true.
请问答案D是什么意思呢，有点看不懂，是指可以通过求covariance 来求correlation是吗？
