FRM Part I · FRM Exam Part I · Calculating and Applying VaR
Portfolio A has a one-day 99% VaR of 10 million and Portfolio B has 6 million. The two portfolios are combined and the combined 99% VaR is 17 million. Which statement is most accurate?
The combined VaR of 17 million exceeds the sum of the stand-alone VaRs of 16 million, violating subadditivity. This illustrates that VaR is not a coherent risk measure, whereas expected shortfall always satisfies subadditivity.
- AThe result violates subadditivity, which shows VaR is not a coherent risk measureCorrect
- BThe result is consistent with a diversification benefit of 1 million
- CThe result implies correlation between A and B is negative
- DThe result is impossible for any coherent risk measure but is normal for expected shortfall
Explanation
Subadditivity requires combined risk to be no more than the sum of the parts: 17 exceeds 10 + 6 = 16. VaR can violate this for non-elliptical distributions, which is why it is not coherent. Expected shortfall is coherent, so it could not produce such a result; a diversification benefit would require a combined figure below 16.
Did you get it right without looking?
One question tells you little. A timed set on Calculating and Applying VaR shows your real accuracy, how long you take and where you lose marks.
More Calculating and Applying VaR questions
- A desk is short a large position in out-of-the-money call options, so its portfolio has negative gamma. A risk manager compares delta-normal…
- A trader holds a long position in a call option on a stock. A risk analyst estimates 1-day VaR using the delta-normal approach, which approx…
- A call option is worth USD 8.00 with the stock at USD 100. Its delta is 0.60 and gamma is 0.02. A full revaluation after the stock falls to …
- A portfolio's one-day loss distribution is approximated by 100 equally likely historical scenarios. The five largest losses, in USD millions…
- A portfolio has two positions: Asset A with USD 6 million and annual volatility 10%, and Asset B with USD 8 million and annual volatility 5%…
- A risk manager simulates a two-asset portfolio using Monte Carlo with correlated normal returns. Asset volatilities are 20% and 30% with cor…