Grossi Flashcards
Users of CAT models
Insurers/reinsurers: exposure
Reinsurance brokers: risk
Capital markets: CAT bonds
Regulators
Emergency Management Agencies
Why regular statistical tools are inappropriate for CAT losses
Insufficient historical claim data
Limited data available due to changing factors
Modules of CAT model
Hazard
Inventory
Vulnerability
Loss
Hazard module
Simulates natural disasters using probabilities of different parameters
Inventory module
Contains properties at risk and their characteristics
Also called the exposure module
Vulnerability module
Estimates susceptibility to damage of each property given simulated CAT
Loss module
Quantifies direct and indirect losses of the event on each property
Three main parameters of a hazard module
Frequency
Severity
Location
These have to do with simulated events, not exposures
Vulnerability module appraoches to estimating damage
Engineering judgment (simple, but arbitrary/not easy to update)
Building response analysis (more accurate, but based on specific buildings)
Class-based BRA
Class-based BRA steps
Divide risks into different classes of buildings
Identify a typical building and analyze in detail
Evaluate building performance to get a damage ratio
Damage ratio
Ratio of repair cost to replacement cost
Two main approaches to determine $ loss from CAT event
Link event parameters directly to expected loss (cannot easily be updated to reflect new information)
First estimate physical damage from an event and use a cost analysis to translate into $
Occurrence Exceedance Probability
Probability that the loss for at least one event exceeds specified loss amount
Useful in per-occurrence excess of loss reinsurance
Aggregate Exceedance Probability
Probability that sum of all losses exceeds specified loss amount
Useful in purchansing aggregate reinsurance
Conditional Exceedance Probability
Probability that the amount on a single event exceeds a specified loss amount, given that the event occurs
Useful for setting reserves after an event occurs
Probable Maximum Loss
Largest loss likely to occur in a given period of time
Occurrence Exceedance Probability, formula
OEP(Li) = 1 - Π(1 - pj)
Sort events in decreasing order by size
Conditional Exceedance Probability formula
CEP(Li) = OEP(Li) / [1 - P(no events)]
Conditions for an insurer to be willing to provide coverage to a risk
(Conditions for a risk to be insurable)
Ability to identify and quantify probability of event and severity of loss
Ability to set premiums for each customer
Considerations in setting rates for CATs
Regulators
Competition
Uncertainty of losses
Correlation of losses
Adverse selection
Moral hazard
Liquidity of assets
Determining whether to provide coverage
As long as P(Loss > nz + A) < p1
p1 is probability of insolvency
n is the # of policies
A is the current surplus
Risk load using standard deviation of OEP curve
How CAT models help determine equitable average annual losses
Structure Attributes
Location Attributes
Regulator concerns with CAT models
Not subject matter experts; makes it tough to evaluate
Modeling firms unwilling to share key proprietary elements
Conflict: present scientifically rational approach to quantifying risk, but may be used to justify increasing rates