NO.PZ2018062016000053
问题如下:
Given the table above, based on the coefficient of variation,which market is least risky?
选项:
A.Hong Kong
B.Australia
C.Italy
解释:
B is correct. A market with lowest CV is the least risky one.
CV(Hong Kong)=20.28/9.2=2.20
CV(Australia)=19.2/10.3=1.86
CV(Italy)=14.72/6.5=2.26
这题我是用S/mean,先用标准差平方,再除以mean 得到结果为Italy,为什么不对?