3. Risk Measures Flashcards
Define a risk measure
Quantitative tool or measure used to assess the level of a risk. It allows us to understand the potential loss from a risk and compare risks together.
Define regulatory capital
Required capital to comply with regulations
Define economic capital
Required capital to comply with the risk appetite of the firm
Define VaR
This risk measure is equivalent to the quantile.
Define expected Shortfall
This risk measure is equivalent to the expected value of the loss knowing that the loss is higher than the quantile.
What are the 4 criterias for a risk measure to be coherent?
- Translation invariance
- Positive homogeneity
- Subadditivity
- Monotonicity
Are the VaR and Expected Shortfall coherent?
ES is coherent, but VaR is not.
How does subbaditivity interacts with the way diversification works in insurance?
When insuring multiple risks, there is generally a benefit called diversification. This is based on the fact that we believe not every bad scenario would occur at the same time; a bad year for home insurance might be a good year for car insurance. By adding risks, we therefore expect that the total is at most each risk seperately, and that most times it is lower.