Distributions for Actuaries
By David Bahnemann · Casualty Actuarial Society · 2015 · CAS Monograph No. 2
Study guide: Exam 8
A brief exposition of the standard probability distributions and their applications by property/casualty actuaries. The focus is on the use of parametric distributions fitted to empirical claim data to solve standard actuarial problems, such as the creation of increased limit factors, the pricing of deductibles, and the evaluation of the effect of aggregate limits. It is the second monograph in the CAS Monograph Series, published in 2015.
On the syllabus
- Exam 8 — objectives B1–B3; Chapters 5 and 6, including errata; the material in Chapters 1-4 is assumed to be familiar.
Foreword
Preface
1 Introduction
- 1.1 Probability Spaces
- 1.2 Random Variables and Probability Distributions
- 1.3 Mathematical Expectation
- 1.4 Random Samples
- 1.5 Fitting Distributions
- 1.6 Problems
2 Claim Size
- 2.1 Claim-Size Random Variables
- 2.2 Limited Moments
- 2.3 Gamma Distributions
- 2.4 Lognormal Distributions
- 2.5 Pareto Distributions
- 2.6 Estimation with Modified Data
- 2.7 Transformations
- 2.8 Inflation Effects
- 2.9 Problems
3 Claim Counts
- 3.1 An Elementary Claim Process
- 3.2 Poisson Claim Processes
- 3.3 Parameter Uncertainty
- 3.4 Negative Binomial Distributions
- 3.5 Claim Contagion
- 3.6 Portfolio Claims
- 3.7 Problems
4 Aggregate Claims
- 4.1 A Discrete Example
- 4.2 Aggregate Distribution Properties
- 4.3 Approximation by Matching Moments
- 4.4 Recursion
- 4.5 Fourier Approximation
- 4.6 Discontinuities
- 4.7 Simulation
- 4.8 Problems
5 Excess Claims
- 5.1 Excess Claim Size
- 5.2 Excess Severity
- 5.3 Layers of Coverage
- 5.4 Excess Claim Counts
- 5.5 Inflation Effects
- 5.6 Aggregate Layer Claims
- 5.7 Problems
6 Limits and Deductibles
- 6.1 Premium Concepts
- 6.2 Increased Limit Factors
- 6.3 Risk Load
- 6.4 Aggregate Limits
- 6.5 Deductibles
- 6.6 Problems
Appendix
- A.1 Distribution Approximation
- A.2 Answers to Selected Problems
- A.3 References
Sources
- Distributions for Actuaries, CAS Monograph Series Number 2 (Casualty Actuarial Society, 2015) — the document: title page, abstract, copyright page and ISBN, foreword, and the contents pages for every chapter and section (read in full; sha256 d4d172f9646852ab018ae3f0df95e5fbdbfabda4db55d6d4596977ed2eaa3ef8; the PDF's front matter lists the print edition's ISBN 978-0-9624762-8-0 and the electronic edition's 978-0-9624762-9-7)
- Distributions for Actuaries, Errata (Casualty Actuarial Society) — the errata sheet the Exam 8 outline assigns with the monograph (corrections to pages 145, 170, 173-175, 177, 182, 189 and 199); not summarised here
- CAS Exam 8 Content Outline, Fall 2026 — the citation and the assigned scope (task statements B1-B3; Chapters 5 and 6)