12.3 Independent Risk
Definition 12.2 Independent Risk = Randomness inherent to the insurance process
Parameter Risk: ability to select correct parameters and appropriate model
- Process Risk: randomness e.g. tossing a die
Use stochastic modeling to analyze independent risk
Focus on periods where episodes of systemic risk were non-existent or minimal
Limit the impact of the historical external episodes and allow us to focus on the independent risk
Supplement with internal and external benchmarking
12.3.1 CoV for Independent Risk
Model the parameter and process risk together
Ideally the model adequately model away the systemic risk so all that is left is the independent risk
Residual should only have independent risk
For small data set: difficult to model away the external systemic risk
Solution: Do not model away past episodes of systemic risk
Use results as starting point and then add a margin for external systemic risks not in data to have a measure of independent and external systemic risk
Complexity of the model should be commensurate with the importance of the total risk margin
Models for outstanding claims liabilities:
GLM and bootstrapping are particularly useful
They can isolate the independent risks
Graphing residuals again AY, age, experience period can used to identify past systemic episodes
Models for premium liabilities:
GLM, bootstrap, Bayesian
Can model frequency and severity CoV then combine
Frequency: Remove past systemic episodes
Severity: Adjust for inflation and seasonality