NO.PZ2020011303000054
问题如下:
A one-year project has a 3% chance of losing USD 10million, a 7% chance of losing USD 3 million, and a 90% chance of gaining USD 1 million.
Suppose that there are two independent identical investments with the properties.
What are (a) the VaR and (b) the expected shortfall for a portfolio consisting of the two investments when the confidence level is 95% and the time horizon is one year?
解释:
Losses (USD) of 20, 13, 9, 6, 2, and −2 have probabilities of 0.0009, 0.0042, 0.054, 0.0049,
The VaR is 9 and ES is
[0.0009×20+0.042×13+(0.05-0.0009-0.0042)×9]/0.05=9.534
ES的计算不是应该是算数平均吗?为什么要去成各自的概率