REQUEST FOR PROPOSAL: Aggregate Loss Distributions:
Convolutions and Time Dependency
December 18, 1996
1. Casualty Actuarial Society (CAS)
The CAS was organized in 1914 as a professional society for
the promotion of actuarial and statistical science as applied
to insurance other than life insurance, such as automobile, liability
other than automobile, workers compensation, fire, homeowners,
commercial multiple peril, and others. Such promotion is accomplished
by communication with those affected by insurance, presentation
and discussion of papers, attendance at seminars and workshops,
collection of a library, research and other means. The membership
of the CAS includes over 2700 actuaries employed by insurance
companies, industry advisory organizations, national brokers,
accounting firms, educational institutions, state insurance departments,
the federal government and independent consultants.
2. Committee on Theory of Risk (CTOR)
The Committee on Theory of Risk is charged with developing
and demonstrating the utility of specific applications of the
theory of risk to various lines of property and casualty insurance.
3. CAS Interest in the Subject
The CAS wishes to enhance the development of tools and models
that improve the accuracy of the estimation of aggregate loss
distributions for blocks of insurance risks. This is an important
step in developing more sophisticated tools for Dynamic Financial
Analysis.
4. Request for Proposal; Project and Proposal Requirements
Aggregate loss distributions are probability distributions
of the total dollar amount of
loss under one or more insurance policies. They combine the separate
effects of the underlying frequency and severity distributions.
Over the past fifteen years, various papers have been published
and models developed that enable actuaries to estimate aggregate
loss distributions. This list includes papers by Heckman &
Meyers, Robertson, Panjer, etc. The issues underlying this RFP
are how to combine aggregate loss distributions for separate but
correlated classes of business as well as how the distribution
changes over time.
The CTOR requests proposals from qualified researchers to produce
a research document that solves one or both of the following two
problems:
A) Assume a book of business is the union of disjoint
classes of business each of which has an aggregate distribution.
These distributions may be given in many different ways. Among
other ways, they may be specified parametrically, e.g. lognormal
with given parameters; they may be given by specifying separate
frequency and severity distributions; e.g. pareto severity and
negative binomial frequency with given parameters or they may
be given as specific discrete distributions. The classes of business
are NOT independent. For this project, assume that you are given
a correlation matrix (or some other easily obtainable measure
of dependency) and that the correlation coefficients vary among
different pairs of classes. The problem is how do you calculate
the aggregate distribution for the whole book.
The Committee has discussed several approaches that may form the
basis for further research. These include:
1) There may be families of distributions (e.g. lognormals or
shifted gammas) such that if each separate distribution is a member
of these families, a closed form and elegant solution is possible.
2) The individual distributions may all be converted to discrete,
piecewise linear, or some other form and then a methodology described
to combine them into a single distribution.
3) Simulation techniques. These are probably the methods most
widely used today by actuaries to solve this problem. The challenge
here would be to create a highly efficient, flexible and sophisticated
algorithm.
4) A somewhat different approach to the ones outlined above would
postulate that the correlation among the classes are all a result
of a number of underlying forces that affect different classes
in different ways. For example, one might attribute all correlation
to be the result of: economic inflation, judicial climate, tort
reform, property catastrophes, health of the economy, and rate
level. The individual aggregate distributions conditional on
specification of these elements would all be independent. One
advantage of this method is that this could be used to deal with
the problem of dependencies among distributions that are different
at different points of the distribution. An example is the effect
a punitive damage cap might have on the aggregate distribution
for both general liability and auto liability.
The Committee is looking for ideas that would, in the judgment
of the Committee, represent a significant advance. The researcher
could produce results along one or more of the above approaches
or present a completely new way of viewing and solving the problem.
The solution(s) should be broad enough to cover most widely used
aggregate loss distributions and should be sophisticated enough
to incorporate parameter uncertainty in some form (e.g. uncertainty
due to model selection, parameter estimation and/or model extrapolation/projection).
B) Assume you know the aggregate loss distribution at
policy inception and you have expected patterns of claims reporting,
losses emerging and losses paid and other pertinent information,
how do you modify the distribution as the policy matures and more
information becomes available? Actuaries have historically dealt
with the problem of modifying the expectation conditional on emerged
information. This expands the problem to continuously modifying
the whole distribution from inception until it decays to a point.
One might expect that there are at least two separate states
that are important. There is the exposure state. It is during
this period that claims can attach to the policy. Once this period
is over no new claims can attach. The second state is the discovery
or development state. In this state claims that already attached
to the policy can become known and their value can begin developing.
These two states may have to be treated separately.
Here again, the Committee is looking for ideas that would, in
the judgment of the Committee, represent a significant advance.
The solution(s) should be broad enough to cover most widely used
aggregate loss distributions.
The research for these projects will be performed under contract
and funded by the CAS. It is expected that the researcher(s)
will work with representatives of the committee on the specific
design of the project.
5. Project Requirements
a. Literature Survey: The paper should survey actuarial
as well as other technical literature for any research relating
to these issues and include a bibliography of such research.
b. Proof of solution: The author would be required to
include within the paper proof that the solution is mathematically
valid.
c. Practical solution: The solution should be presented
in a form that a practicing actuary can implement in a practical
manner solely from reading the paper. Inclusion of software that
would be available to CAS members would be a plus. At a minimum,
an algorithm in some suitable form must be provided.
6. Proposal Requirements
Proposals should include a clear outline of the work that
will be performed and the time frame in which it will be performed
(including key dates). The more specific the better.
This proposal should be reviewed in conjunction with the attached
consulting agreement(s) which defines the terms and conditions
under which the work is performed.
The proposal should be accompanied by the resumes of the researcher(s),
indicating how their background, education, and experience bear
on their qualifications to undertake the research.
Respondents should demonstrate their interest in and familiarity
with the application of loss distributions to insurance problems
by including a resume (if a firm, of the principal consultant(s)
performing or directing the work) showing relevant work/research
experience and professional accomplishments (e.g.. papers published).
The contract will be awarded by the CAS to the respondent who,
in the judgment of the CTOR and entirely on the basis of his or
her written proposal, is best able to perform the work as specified
herein. If the CTOR determines that no proposal meets the requirements
of the RFP, then no contract will be awarded.
Receipt of proposals will be acknowledged by providing each respondent
with a list of all respondents. Respondents not awarded the contract
will be so informed shortly thereafter.
Interested researchers should submit their proposals and any questions
in writing to:
Isaac Mashitz
Casualty Actuarial Society
1100 N. Glebe Road, Suite 600
Arlington, VA 22201
Phone: (703) 276-3100
Fax: (703) 276-3108
The proposals will be reviewed by members of a subcommittee of
CTOR. The current membership of the CTOR includes:
Roger Hayne, Chairperson
Rodney Kreps, Vice Chairperson
John Aquino
Ward M. Brooks
Bob Finger
Louise Francis
Jim Garven
Robin Gillam
Phil Heckman
Stuart Klugman
Isaac Mashitz
Glenn Meyers
Gary Patrik
Richard Roth, Jr.
Gary Venter
William F. Weimer
7. Schedule
January 20, 1997
Deadline for questions (must be written) from researchers
regarding the RFP.
February 1, 1997
All written questions together with their answers will be
distributed to all proposers.
February 17, 1997
Proposal deadline - end of business day
April 4, 1997
Proposal selection by CTOR
December 1, 1997
Report due
8. Compensation
A maximum total of $40,000 is available to be awarded to one
or more reseachers. Payment of award(s) will be contingent upon
delivery of an acceptable research product.
9. Presentation, Ownership and Publication of Report
If asked, the researcher(s) agree to be available to present
the report at a CAS meeting or seminar. If travel is required,
reasonable expenses will be paid in addition to the compensation
provided in Section 8.
The CAS intends to copyright the report and to submit it to the
CAS Committee on Review of Papers for consideration as a CAS Proceedings
paper. Alternately, the CAS may publish the report in the CAS
Forum. It is intended that the results of the report can be used
freely by any interested party. The research will be considered
work-for-hire and all rights thereto belong to the CAS. However,
appropriate credit will be given to the researcher(s).
Guidelines for submitting papers for publishing in the CAS Proceedings
are as stated in the 1996 CAS Yearbook (pages 255-263), a copy
of which is available upon request, or on the CAS Web Site.
10. Consulting Agreement
Aggregate Loss Distributions: Convolutions and Time Dependency
This agreement is made by and between the Casualty Actuarial Society
("CAS") and ___________________ ("CONSULTANT").
The CAS agrees to contract for the services of the CONSULTANT,
and the CONSULTANT agrees to provide services under the terms
and conditions of this agreement.
I. STATEMENT OF WORK
The CONSULTANT shall provide consulting services on behalf
of the CAS to produce a research document discussing existing
actuarial guidance on the subject of risk transfer and the reinsurance
industry responses prompted by the risk transfer criteria of certain
accounting standards, or related areas the CAS or the Committee
on Theory of Risk ("CTOR") may request during the period
of performance, as specified in the Request for Proposal, which
is hereby incorporated herein by reference.
II. PAYMENT FOR SERVICES
In full consideration of the consulting services provided
hereunder, the CAS agrees to pay CONSULTANT a fixed fee of _____
plus reasonable expenses incurred at the request of the CAS or
CTOR, based upon a payment schedule to be agreed upon.
III. PERIOD OF PERFORMANCE
CONSULTANT shall be available for a minimum of ________ and
a maximum of ________ days for the period of performance beginning
_____ and ending _____. This period of performance shall not
be changed without the written authorization of the CAS or CTOR.
IV. NOT-TO-EXCEED TOTAL LIMIT
Total payment under this contract including reasonable expenses
incurred at the request of the CAS or CTOR shall not exceed _____,
unless authorized in writing by CTOR or the CAS.
V. INDEPENDENT CONTRACTOR
It is understood and agreed that CONSULTANT is an independent
contractor in the performance of this Agreement, CONSULTANT is
not an agent of CTOR or the CAS, and CONSULTANT is not authorized
to act on behalf of CTOR or the CAS.
CONSULTANT shall assume full responsibility for payment of all
federal, state and local taxes with respect to performance of
the CONSULTANT's obligations under this Agreement.
VI. RIGHT TO ACT AS CONSULTANT
CONSULTANT warrants to the CAS that he/she is not subject
to any obligations, contracts, covenants or restrictions that
would prevent him from entering into or carrying out the provisions
of this Agreement.
VII. TERMINATION
This Agreement may be terminated by either party at any time
by giving written notice of such termination to the other party.
Upon receipt of such written notice by either party, no further
charges will be made under this Agreement. Termination shall
not affect the CONSULTANT's obligations under articles IX and
X.
VIII. HOLD HARMLESS
CONSULTANT shall indemnify and hold CTOR and the CAS harmless
from any and all suits, claims, damages or losses whatsoever,
resulting from any act or omission of the CONSULTANT, his employees,
agents, and subcontractors in his performance under this Agreement.
IX. CONFIDENTIALLY
CONSULTANT warrants that, to protect the privacy of respondents
to surveys conducted, CONSULTANT will collect only the data needed
for the purpose of their inquiry and inform each potential survey
respondent about the general nature and sponsorship of the inquiry
and the intended uses of the data.
CONSULTANT acknowledges that information it obtains in the performance
of this Agreement is valuable and confidential. Accordingly,
CONSULTANT agrees not to disclose any such information to any
person not authorized by CTOR or the CAS to receive it. Upon
completion of the work, CONSULTANT shall deliver to CTOR all data,
documents, reports, surveys, or other materials prepared by CONSULTANT
in his performance under this Agreement.
X. DISCOVERIES
CONSULTANT will promptly disclose to CTOR all discoveries
made and ideas conceived by CONSULTANT in his performance under
this agreement. CONSULTANT assigns to the CAS all right and title
to such discoveries and ideas, and agrees to execute any and all
such documents, including copyright assignments, as the CAS deems
necessary to secure it all right, title and interest.
XI. AMENDMENT
This Agreement may be amended only by a written document,
signed by both the CAS and CONSULTANT.
XII. ASSIGNMENT
CONSULTANT may not assign this agreement or any right hereunder.
Any such attempted assignment shall be void.
XIII. GOVERNING LAW
This Agreement shall be governed by the laws of ___________
(the jurisdiction of CONSULTANT's principal place of business).
CONSULTANT
by
Name __________________________
Title ___________________________
Date ___________________________
Casualty Actuarial Society
by
Name ___________________________
Title ____________________________
Date ____________________________




