ABy Admin
May 14'23

Exercise

You are given:

Number of Claims Probability Claim Size Probability


0 1/5
1 3/5 25
150
1/3
2/3
2 1/5 50
200
2/3
1/3


Claim sizes are independent.


Calculate the variance of the aggregate loss.

  • 4,050
  • 8,100
  • 10,500
  • 12,510
  • 15,612

Copyright 2023. The Society of Actuaries, Schaumburg, Illinois. Reproduced with permission.

ABy Admin
May 14'23

Key: B

First obtain the distribution of aggregate losses:

Value Probability
0 [math]1 / 5[/math]
25 [math](3 / 5)(1 / 3)=1 / 5[/math]
100 [math](1 / 5)(2 / 3)(2 / 3)=4 / 45[/math]
150 [math](3 / 5)(2 / 3)=2 / 5[/math]
250 [math](1 / 5)(2)(2 / 3)(1 / 3)=4 / 45[/math]
400 [math](1 / 5)(1 / 3)(1 / 3)=1 / 45[/math]

[[math]]\begin{aligned} & \mu=(1 / 5)(0)+(1 / 5)(25)+(4 / 45)(100)+(2 / 5)(150)+(4 / 45)(250)+(1 / 45)(400)=105 \\ & \sigma^{2}=(1 / 5)\left(0^{2}\right)+(1 / 5)(25)+(4 / 45)\left(100^{2}\right)+(2 / 5)\left(150^{2}\right)+(4 / 45)\left(250^{2}\right) \\ & +(1 / 45)\left(400^{2}\right)-105^{2}=8100 \end{aligned}[[/math]]

Copyright 2023. The Society of Actuaries, Schaumburg, Illinois. Reproduced with permission.

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