NO.PZ2018062016000069
问题如下：
Which correlation coefficient shows the strongest linear relationship between two variables?
选项：
A. 0.5
B. -0.9
C. 0
解释：
B is correct. The closer the absolute value of correlation coefficients are to 1, the stronger the linear relationship may exhibit. The uncorrelated variables may have a correlation of 0, which means an absence of any linear relationship.
可以说明下为什么-0.90 最接近1，为什么不是0.50最接近呢?
