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

fdzh · 2023年10月23日

看不懂答案,麻烦解释一下

NO.PZ2023091701000090

问题如下:

A portfolio manager invests $100 million in a 5-year inverse floater paying 18% – 2 × LIBOR. Assume that the modified duration of a 6% 5-year bond is 4.5 years, and the inverse floater is just before a reset day. The worst change in yields at the 95% level over a month is 0.66%. What is the VaR of this inverse floater at the 95% level over a month?

选项:

A.$3.0 million B.$5.9 million C.$8.9 million D.$10.5 million

解释:

18% – 2 × L = 3 × 6% – 2 × L

(18% – 2 × L) + (2 × L) = 3 × 6%

DIF = 3 × D6% = 3 × 4.5 = 13.5

VARIF = D × P (worst change in yields) = 13.5 × 100million × 0.66% = 8.91million

如题

1 个答案

DD仔_品职助教 · 2023年10月26日

嗨,爱思考的PZer你好:


同学你好,

计算inverse floater久期的思路是:一个普通的固定利息债券(题目给了是6%的coupon bond) = 一个libor浮动利息债券 + 一个libor反向浮动债券,

假设浮动利息债券的权重是w1, 反向浮动利息债券的权重是w2

  1. w1 + w2 = 1,
  2. 我们要让浮动利息和反向浮动利息加起来正好等于题目给你的6%的coupon, 所以w1 * (L+spread) + w2 * (18%-2L) = 6%,等式左边带有L这个浮动利息的项目必须消掉,这样才能等于右边的固定利息6%,所以w1 * L - 2*w2 * L=0, 所以w1 = 2w2,结合上面的等式,解出来w1=2/3, w2 = 1/3.
  3. 固定利息债券的久期=4.5, 所以4.5 = w1 * 浮动利息债券的久期 + w2 * 反向浮动利息债券的久期,题目还说“just before a reset day”,所以浮动利息债券的久期为0,所以4.5 = 0 + w2 * 反向浮动利息债券的久期,所以反向浮动利息债券的久期 = 3 * 4.5 = 13.5

最后inverse floater的VAR = D × P (worst change in yields) = 13.5 × 100million × 0.66% = 8.91million

----------------------------------------------
加油吧,让我们一起遇见更好的自己!