问题如下图：
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解释：
理解答案里的解题思路，但还想问下，CVAR的定义就是how portfolio VAR would change approximately if the component was deleted from the portfolio，为什么这里又不能用呢？什么时候才能用CVAR呢？感谢！
NO.PZ2016071602000011问题如下A risk manager assumes ththe joint stribution of returns is multivariate normancalculates the following risk measures for a two-asset portfolio:If asset 2 is oppefrom the portfolio, whis the rection in portfolio VAR?A.US15.0B.US38.3C.US44.0US46.6B is correct. This is 61.6 minus the portfolio Vof asset 1 alone, whiis US23.3, for a fferenof 38.3.老师， 为什么 我们不能用 VContribution 那一列呢 ？ 就是 Portfolio op 了 2 资产 , 直接就是少了 44 ？
NO.PZ2016071602000011 问题如下 A risk manager assumes ththe joint stribution of returns is multivariate normancalculates the following risk measures for a two-asset portfolio:If asset 2 is oppefrom the portfolio, whis the rection in portfolio VAR? A.US15.0 B.US38.3 C.US44.0 US46.6 B is correct. This is 61.6 minus the portfolio Vof asset 1 alone, whiis US23.3, for a fferenof 38.3. 如题
NO.PZ2016071602000011问题如下A risk manager assumes ththe joint stribution of returns is multivariate normancalculates the following risk measures for a two-asset portfolio:If asset 2 is oppefrom the portfolio, whis the rection in portfolio VAR?A.US15.0B.US38.3C.US44.0US46.6B is correct. This is 61.6 minus the portfolio Vof asset 1 alone, whiis US23.3, for a fferenof 38.3.拿掉组合2，整个var不应该就是减去var2吗？为什么还要剪去var1
NO.PZ2016071602000011 问题如下 A risk manager assumes ththe joint stribution of returns is multivariate normancalculates the following risk measures for a two-asset portfolio:If asset 2 is oppefrom the portfolio, whis the rection in portfolio VAR? A.US15.0 B.US38.3 C.US44.0 US46.6 B is correct. This is 61.6 minus the portfolio Vof asset 1 alone, whiis US23.3, for a fferenof 38.3. 老师组合中两个资产拿掉一个资产不应该用CVaR来考虑吗？所以拿掉的部分不就是组合中减少的VAR了吗？那不就是44吗？这个思路错在哪里
NO.PZ2016071602000011问题如下A risk manager assumes ththe joint stribution of returns is multivariate normancalculates the following risk measures for a two-asset portfolio:If asset 2 is oppefrom the portfolio, whis the rection in portfolio VAR? A.US15.0 B.US38.3 C.US44.0 US46.6B is correct. This is 61.6 minus the portfolio Vof asset 1 alone, whiis US23.3, for a fferenof 38.3.我的理解是如果把第一个资产拿掉的话，这是portfolio var是多少。 老师在课堂上不是说过component var考虑了分散化，所有资产的cvar加和等于portfolio var。那么为什么不用原来的portfolio v减去asset 1的cv而得到新的porfolio var呢
