Market Risk Measurement and Management Flashcards
The relationship between arithmetic rt and geometric Rt returns using a Taylor’s series expansion for the natural log
Empirical and estimated VaR
Lognormal VaR
Delta-normal VaR
- Delta-normal VaR assumes that:
- returns are normally distributed (or multivariate normal)
- [delta] the portfolio/position exposures, to the risk factor(s), are expressed linearly
Sprectral risk measure
A spectral risk measure is a risk measure given as a weighted average of outcomes where bad outcomes are included with larger weights
Age-weighted historical simulation (Boudoukh, Richardson and Whitelaw approach (BRW))
- The data is weighted using a weighting function
- w(1) = w(1)
- w(2) = λw(1)
- w(3) = λ2w(1)
- …
Volatility-weighted historical simulation (Hull and White (HW))
- rt,i = the return of asset i on day t
- σt,i = the estimated volatility on day t
- σT,i = the most recent estimation of volatility
Filtered historical simulation advantages
- It enables us to combine the non-parametric attractions of HS with a sophisticated (e.g., GARCH) treatment of volatility, and so take account of changing market volatility conditions.
- It is fast, even for large portfolios.
- As with the earlier HW approach, FHS allows us to get VaR and ES estimates that can exceed the maximum historical loss in our data set.
- It maintains the correlation structure in our return data without relying on knowledge of the variance-covariance matrix or the conditional distribution of asset returns.
- It can be modified to take account of autocorrelation or past cross-correlations in asset returns.
- It can be modified to produce estimates of VaR or ES confidence intervals by combining it with an OS or bootstrap approach to confidence interval estimation.
- There is evidence that FHS works well.
Risk axiomes
Average correlation between n assets
Market risk consists of four types of risk
- Equity risk
- Interest-rate risk
- Currency risk
- Commodity risk
Credit migration
The risk that the credit quality of a debtor decreases
Joint probability of default for two binomial events
Standard deviation of a binomially distributed variable X
CVaR credit value-at-risk
Measures the maximum loss of a portfolio of correlated debt with a certain probability for a certain timeframe
DV01