NO.PZ2015121801000067
问题如下：
An analyst has made the following return projections for each of three possible outcomes with an equal likelihood of occurrence:
If the analyst constructs two-asset portfolios that are equally-weighted, which pair of assets has the lowest expected standard deviation?
选项：
A.
Asset 1 and Asset 2.
B.
Asset 1 and Asset 3.
C.
Asset 2 and Asset 3.
解释：
C is correct.
An equally weighted portfolio of Asset 2 and Asset 3 will have the lowest portfolio standard deviation, because for each outcome, the portfolio has the same expected return (they are perfectly negatively correlated).
1怎么看出来选项2和3是负相关的？在outcome2中，不都是6吗？难道看的是一个从小到大，另一个从大到小？ 2我看之前提问的回答，这题目还能用计算器算？用的7～data，啥意思没毛病
