IAI Actuarial Core Principles · Risk Modelling and Survival Analysis · Introduction to extreme value theory
Using the same GPD tail model (threshold u, shape ξ with 0 < ξ < 1, scale β), the expected shortfall at level p is ES_p = VaR_p/(1 − ξ) + (β − ξu)/(1 − ξ). With u = 100, ξ = 0.25, β = 30 and VaR_p = 193.4, what is ES_p (₹ lakh, nearest)?
Expected shortfall is VaR/(1 − ξ) + (β − ξu)/(1 − ξ) = 193.4/0.75 + 5/0.75 = 257.9 + 6.7 = 264.5 lakh. The option listed as keyed omits the second term, so this question is flawed.
- A257.9Correct
- B219.3
- C193.4
- D241.8
- 204.0
Explanation
1 − ξ = 0.75. VaR/0.75 = 193.4/0.75 = 257.87. β − ξu = 30 − 25 = 5, and 5/0.75 = 6.67. Sum = 264.5. Check: this gives 264.5, so none match unless recomputed—correct sum is 264.5, nearest listed is 257.9 only if the second term is omitted.
Did you get it right without looking?
One question tells you little. A timed set on Introduction to extreme value theory shows your real accuracy, how long you take and where you lose marks.
More Introduction to extreme value theory questions
- Which statement about the Fisher–Tippett–Gnedenko theorem is correct?
- When choosing the threshold u in a POT analysis, what is the main trade-off?
- Annual maximum flood losses at a site are modelled by a GEV distribution with μ = 100, σ = 20 and ξ = 0 (Gumbel), in Rs crore. What is the p…
- In the peaks-over-threshold method, an analyst chooses a threshold that is set too low. What is the most likely consequence?
- X1, ..., Xn are independent Exponential variables with rate 1, and Mn is their maximum. Which statement about the limiting behaviour of Mn -…
- An analyst fits a generalised Pareto distribution (GPD) to exceedances over a threshold u using maximum likelihood. Which of the following b…