开发者:上海品职教育科技有限公司 隐私政策详情

应用版本:4.2.11(IOS)|3.2.5(安卓)APP下载

梦梦 · 2024年03月03日

有两个问题

NO.PZ2020011303000068

问题如下:

Consider a position consisting of a USD 10,000 investment in asset X and a USD 20,000 investment in asset Y. Assume that the daily volatilities of X and Y are 1% and 2% and that the coefficient of correlation between their returns is 0.3. What is the five-day VaR with a 97% confidence level?

解释:

The standard deviation of the daily changes in the assets are (in USD) 100 and 400. The standard deviation of the daily change in the portfolio is (100^2+400^2+2×100×400×0.3)^0.5=440.5

The standard deviation of the five-day change is the square root of 5 multiplied by the one-day standard deviation, which is USD 984.9. The 97% VaR is 1.88 times this, which is USD 1852.4.

题目问:有一个头寸包含10,000$的资产X20,000$的资产Y,假设每日波动是1%2%,相关系数是0.3,求597%VaR?

每日波动的dollar值:X=10,000*1%=100Y=20,000*2%=400

组合每日的波动=(100^2+400^2+2×100×400×0.3)^0.5=440.5

597%VAR=440.5*(5)^0.5*1.88=1852.4


老师您好,这是您之前对某个学生的解答,但有两个问题,第一个您帮我看看我的公式有问题吗,我算了很多遍都是2.16%,并不是1.47%。

第二个问题是方法二为什么不计算X资产和Y资产的权重呢?

2 个答案

pzqa27 · 2024年03月06日

嗨,努力学习的PZer你好:


X占1/3是因为组合中有10000是X,20000是Y。X和Y的占比是根据value的比例来确定的。在第二种计算方法中,X的波动率是10000*1%得到的100,因此在计算过程中实际上是考虑了X的value,因此不用把权重纳入其中。

----------------------------------------------
虽然现在很辛苦,但努力过的感觉真的很好,加油!

pzqa27 · 2024年03月04日

嗨,爱思考的PZer你好:


第一个问题:你没开根号。

第二个问题:权重是按value为权重,因此第二种算法中已经考虑了各个资产对应的value,它算的是美金形式的波动率,所以不用再额外计算权重了。

----------------------------------------------
就算太阳没有迎着我们而来,我们正在朝着它而去,加油!

梦梦 · 2024年03月06日

“权重是按value为权重,因此第二种算法中已经考虑了各个资产对应的value,它算的是美金形式的波动率,所以不用再额外计算权重了。”这句话还是不太明白,不需要考虑X资产占1/3,Y占2/3了?

  • 2

    回答
  • 0

    关注
  • 404

    浏览
相关问题

NO.PZ2020011303000068问题如下Consir a position consisting of a US10,000 investment in asset X ana US20,000 investment in asset Y. Assume ththe ily volatilities of X anY are 1% an2% anththe coefficient of correlation between their returns is 0.3. Whis the five-y Vwith a 97% confinlevel? The stanrviation of the ily changes in the assets are (in US 100 an400. The stanrviation of the ily change in the portfolio is (100^2+400^2+2×100×400×0.3)^0.5=440.5The stanrviation of the five-y change is the square root of 5 multipliethe one-y stanrviation, whiis US984.9. The 97% Vis 1.88 times this, whiis US1852.4. 题目问有一个头寸包含10,000$的资产X,20,000$的资产Y,假设每日波动是1%和2%,相关系数是0.3,求5天97%的VaR?每日波动的llar值X=10,000*1%=100,Y=20,000*2%=400组合每日的波动=(100^2+400^2+2×100×400×0.3)^0.5=440.55天97%的VAR=440.5*(5)^0.5*1.88=1852.4 老师好,1、黑线上半部分我哪里想的不对吗?2、答案的解析,也就是黑线下半部分,我不明白为什么V(X+Y)就直接用100和400来算了,我明白100和400是怎么来的哈,但是100和400只是资产价值啊,100^2难道就相当于V(X)?400^2相当于V(Y)?cov(X,Y)相当于0.3*100*400?不懂答案的含义是什么意思,100就是西格玛X?400就是西格玛Y?3、如果用excel计算的话,有概率计算分位点是什么函数?有分位点计算累计概率又是什么函数呢

2024-07-24 16:11 2 · 回答

NO.PZ2020011303000068问题如下 Consir a position consisting of a US10,000 investment in asset X ana US20,000 investment in asset Y. Assume ththe ily volatilities of X anY are 1% an2% anththe coefficient of correlation between their returns is 0.3. Whis the five-y Vwith a 97% confinlevel? The stanrviation of the ily changes in the assets are (in US 100 an400. The stanrviation of the ily change in the portfolio is (100^2+400^2+2×100×400×0.3)^0.5=440.5The stanrviation of the five-y change is the square root of 5 multipliethe one-y stanrviation, whiis US984.9. The 97% Vis 1.88 times this, whiis US1852.4. 题目问有一个头寸包含10,000$的资产X,20,000$的资产Y,假设每日波动是1%和2%,相关系数是0.3,求5天97%的VaR?每日波动的llar值X=10,000*1%=100,Y=20,000*2%=400组合每日的波动=(100^2+400^2+2×100×400×0.3)^0.5=440.55天97%的VAR=440.5*(5)^0.5*1.88=1852.4 97%1.88是怎么来的求画图。。。

2023-05-08 20:49 1 · 回答

NO.PZ2020011303000068问题如下Consir a position consisting of a US10,000 investment in asset X ana US20,000 investment in asset Y. Assume ththe ily volatilities of X anY are 1% an2% anththe coefficient of correlation between their returns is 0.3. Whis the five-y Vwith a 97% confinlevel? The stanrviation of the ily changes in the assets are (in US 100 an400. The stanrviation of the ily change in the portfolio is (100^2+400^2+2×100×400×0.3)^0.5=440.5The stanrviation of the five-y change is the square root of 5 multipliethe one-y stanrviation, whiis US984.9. The 97% Vis 1.88 times this, whiis US1852.4. 题目问有一个头寸包含10,000$的资产X,20,000$的资产Y,假设每日波动是1%和2%,相关系数是0.3,求5天97%的VaR?每日波动的llar值X=10,000*1%=100,Y=20,000*2%=400组合每日的波动=(100^2+400^2+2×100×400×0.3)^0.5=440.55天97%的VAR=440.5*(5)^0.5*1.88=1852.4 最后算var的时候乘以金额

2023-03-17 17:24 1 · 回答

NO.PZ2020011303000068问题如下Consir a position consisting of a US10,000 investment in asset X ana US20,000 investment in asset Y. Assume ththe ily volatilities of X anY are 1% an2% anththe coefficient of correlation between their returns is 0.3. Whis the five-y Vwith a 97% confinlevel? The stanrviation of the ily changes in the assets are (in US 100 an400. The stanrviation of the ily change in the portfolio is (100^2+400^2+2×100×400×0.3)^0.5=440.5The stanrviation of the five-y change is the square root of 5 multipliethe one-y stanrviation, whiis US984.9. The 97% Vis 1.88 times this, whiis US1852.4. 题目问有一个头寸包含10,000$的资产X,20,000$的资产Y,假设每日波动是1%和2%,相关系数是0.3,求5天97%的VaR?每日波动的llar值X=10,000*1%=100,Y=20,000*2%=400组合每日的波动=(100^2+400^2+2×100×400×0.3)^0.5=440.55天97%的VAR=440.5*(5)^0.5*1.88=1852.4 U 减去Z 乘波动公式不能适用吗?和例题一样啊。反而解题公式没看到过。请详细说说。为啥不能用讲义上的公式,十分困惑。多谢

2023-03-11 15:01 2 · 回答