Title: NAIC Catastrophe Computer Modeling Handbook
1NAIC Catastrophe Computer Modeling Handbook
2Purpose of the Handbook
What on Earth do we need this for?
- The purpose of the Catastrophe Modeling Handbook
is to explore in some detail catastrophe computer
models and to discuss issues that have arisen or
can be expected to arise from their use. - Used by insurance regulators to review models
primarily used in underwriting, rate-making and
solvency procedures.
3User Perspectives of Models
Well heres what we think...
- Insurers Perspective
- Old rate making methods underestimate the cost of
insuring catastrophe prone areas. - Consumers Perspective
- Modelers must disclose input and output so
independent tests can be run to assure that
results are reasonable.
4User Perspectives of Models (continued)
- Regulators Perspective
- Must learn to replace traditional models with a
methodology that is in its relative infancy in
terms of producing consistently reliable results. -
- Must work with modelers to provide enough
disclosure to make informed decisions while
preserving the confidentiality of proprietary
details.
5Components of the Model
The whole is greater than the sum of its parts.
- Science Module
- Physical characteristics about the catastrophe
(factors include wind speeds, landfall
location, magnitude, location of fault,
liquefaction potential). - Engineering Module
- Estimates the effect of catastrophic events on
different types of structures (factors include
age of structure, construction type, attachment
anchoring). - Insurance Module
- Estimates the insured damage at a location
(factors include guaranteed replacement cost
multiplier, deductible, reinsurance limits).
6Considerations of Model Inputs
Whatever goes in...
- Models use expected future exposures as the basis
for analysis whereas more traditional techniques
use historical data. - Models can be modified to utilize exposure data
maintained by companies and statistical agents. - Currently, exposure data is not collected
specifically to be used in catastrophe modeling
which can significantly impact a models results.
7Model Output
must come out.
- Average Annual Losses
- Provides an estimate of the amount a company
needs to collect from policyholders each year to
fund long-run catastrophe losses. - Loss Costs
- Defined as Average Annual Losses divided by the
number of exposure units giving rise to those
losses.
8Model Output (continued)
- Distribution of Losses
- The probability distribution that a company will
experience losses less than or equal to a
specified amount, used to - estimate parameters when the form of the
distribution has been assumed - create an empirical loss distribution.
- Exceeding Probability Distribution
- Represents the probability that a client
companys portfolio of risks will experience
losses greater than a given amount.
9Model Output (continued)
- Individual Event Losses
- Shows the event characteristics as well as
detailed estimates on the losses for a specific
simulated catastrophic event for a specified
portfolio or risks. - Historical Event Losses
- Characteristics of a particular historical event
are used to simulate the loss experience for a
specific exposure distribution, typically the
clients current distribution.
10Model Validation, Updating and Evaluation
Because you can never be too sure.
- Accuracy and Comparison to Historical Data
- Compare modeled results to actual results for a
historic event. - Convergence
- Confirm the model was calculated using sufficient
iterations.
11Model Validation, Updating and Evaluation
(continued)
- Expert Opinion/Peer Review
- Confirm that modelers disclose the extent to
which the model has been verified or
substantiated by independent expert opinion. - Input Data Provided by Company
- Modelers should perform validation checks on
provided data and disclose how invalid data is
treated in their model.
12Model Validation, Updating and Evaluation
(continued)
- Logical Relationship to Risk
- Verify that modeled loss costs increase as
exposure to potential loss is assumed to increase
and should decrease as exposures decrease. - Model Updates
- Verify that modelers update zip code databases on
a regular basis.
13Model Validation, Updating and Evaluation
(continued)
- Probabilistic Range
- Verify that models produce results over ranges
that can be reasonably expected. - Sensitivity
- Test to see how a change in input or in a model
parameter affects the outputs. - Stability
- Verify that sampling and aggregation have a
negligible contribution to error.
14Model Validation, Updating and Evaluation
(continued)
- Questions to Ask About
- Company data input to models
- Computer simulation models
- Model output
15Proprietary Information
Everything is Sacred.
- Two Conflicting Sides of the Coin
- Catastrophe modelers are dependent upon keeping
their model assumptions and parameters out of the
hands of competitors. - Regulators are governed by Freedom of Information
of Sunshine laws concerning what information must
be disclosed to the general public.
16Proprietary Information (continued)
- Three Regulator Options to the Dilemma
- These laws occasionally contain a waiver from
disclosing data if it considered to be a trade
secret. - Modelers may allow regulators to perform an
on-site visit and assist regulators in reviewing
and understanding a specific model and its
application to insurer data. - Regulators may ask state seismologists and
geologists to assist them in understanding
scientific aspects of the modeling process.
17Education and Outreach
- Explanation of how computer models are used in
rate-making or portfolio management. - An overview of the technical information that the
models contain should be supplied. - Educational materials should be prepared to
increase public awareness of catastrophe risk. - Educational materials should be developed and
distributed through the mail and the Internet. - Establish speakers bureaus for cities, towns,
civic/business/religious organizations and
educational institutions to identify available
resources.
18Other Suggestions
Let us not forget the kitchen sink!
- Related Activities
- Actuarial Standards for Model Use
- Using Models Outside the Actuarys Area of
Expertise (Property and Casualty) - Pre-Tax Loss Reserves for Companies
- NAIC has been working on a proposal for a
statutory tax deductible pre-event catastrophe
reserve.
19Contact Information
As if this isnt more than you wanted to know!
For a copy of the NAICs Catastrophe Computer
Modeling Handbook, contact Davin Cermak at
dcermak_at_naic.org, or NAIC 2301
McGee, Suite 800 Kansas City, MO 64108