Dedication |
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v | |
Preface |
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vii | |
Introduction |
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ix | |
1 Claims Reserving and Pricing with Run-Off Triangles |
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1 | |
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1.1 The evolving nature of claims and reserves |
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1 | |
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4 | |
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1.2.1 Basic chain ladder method |
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5 | |
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1.2.2 Inflation-adjusted chain ladder method |
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8 | |
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1.3 The average cost per claim method |
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11 | |
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1.4 The BornhuetterFerguson or loss ratio method |
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14 | |
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1.5 An example in pricing products |
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19 | |
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1.6 Statistical modeling and the separation technique |
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26 | |
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27 | |
2 Loss Distributions |
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35 | |
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2.1 Introduction to loss distributions |
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35 | |
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2.2 Classical loss distributions |
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36 | |
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2.2.1 Exponential distribution |
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36 | |
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2.2.2 Pareto distribution |
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39 | |
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43 | |
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2.2.4 Weibull distribution |
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45 | |
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2.2.5 Lognormal distribution |
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47 | |
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2.3 Fitting loss distributions |
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51 | |
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2.3.1 Kolmogorov -Smirnoff test |
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52 | |
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2.3.2 Chi-square goodness-of-fit tests |
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54 | |
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2.3.3 Akaike information criteria |
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58 | |
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2.4 Mixture distributions |
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58 | |
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2.5 Loss distributions and reinsurance |
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61 | |
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2.5.1 Proportional reinsurance |
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62 | |
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2.5.2 Excess of loss reinsurance |
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62 | |
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68 | |
3 Risk Theory |
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77 | |
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3.1 Risk models for aggregate claims |
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77 | |
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3.2 Collective risk models |
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78 | |
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3.2.1 Basic properties of compound distributions |
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79 | |
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3.2.2 Compound Poisson, binomial and negative binomial distributions |
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79 | |
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3.2.3 Sums of compound Poisson distributions |
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85 | |
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3.2.4 Exact expressions for the distribution of S |
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87 | |
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3.2.5 Approximations for the distribution of S |
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92 | |
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3.3 Individual risk models for S |
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94 | |
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3.3.1 Basic properties of the individual risk model |
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95 | |
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3.3.2 Compound binomial distributions and individual risk models |
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97 | |
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3.3.3 Compound Poisson approximations for individual risk models |
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98 | |
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3.4 Premiums and reserves for aggregate claims |
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99 | |
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3.4.1 Determining premiums for aggregate claims |
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99 | |
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3.4.2 Setting aside reserves for aggregate claims |
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103 | |
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3.5 Reinsurance for aggregate claims |
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107 | |
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3.5.1 Proportional reinsurance |
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109 | |
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3.5.2 Excess of loss reinsurance |
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111 | |
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3.5.3 Stop-loss reinsurance |
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116 | |
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120 | |
4 Ruin Theory |
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129 | |
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4.1 The probability of ruin in a surplus process |
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129 | |
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4.2 Surplus and aggregate claims processes |
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129 | |
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4.2.1 Probability of ruin in discrete time |
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132 | |
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4.2.2 Poisson surplus processes |
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132 | |
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4.3 Probability of ruin and the adjustment coefficient |
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134 | |
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4.3.1 The adjustment equation |
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135 | |
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4.3.2 Lundberg's bound on the probability of ruin ψ(U) |
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138 | |
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4.3.3 The probability of ruin when claims are exponentially distributed |
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140 | |
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4.4 Reinsurance and the probability of ruin |
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146 | |
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4.4.1 Adjustment coefficients and proportional reinsurance |
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147 | |
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4.4.2 Adjustment coefficients and excess of loss reinsurance |
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149 | |
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152 | |
5 Credibility Theory |
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159 | |
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5.1 Introduction to credibility estimates |
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159 | |
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5.2 Classical credibility theory |
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161 | |
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161 | |
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5.2.2 Partial credibility |
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163 | |
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5.3 The Bayesian approach to credibility theory |
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164 | |
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5.3.1 Bayesian credibility |
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164 | |
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5.4 Greatest accuracy credibility theory |
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170 | |
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5.4.1 Bayes and linear estimates of the posterior mean |
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172 | |
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5.4.2 Predictive distribution for Xn+1 |
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175 | |
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5.5 Empirical Bayes approach to credibility theory |
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176 | |
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5.5.1 Empirical Bayes credibility Model 1 |
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177 | |
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5.5.2 Empirical Bayes credibility Model 2 |
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180 | |
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183 | |
6 No Claim Discounting in Motor Insurance |
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191 | |
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6.1 Introduction to No Claim Discount schemes |
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191 | |
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6.2 Transition in a No Claim Discount system |
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193 | |
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6.2.1 Discount classes and movement in NCD schemes |
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193 | |
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6.2.2 One-step transition probabilities in NCD schemes |
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195 | |
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6.2.3 Limiting distributions and stability in NCD models |
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198 | |
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6.3 Propensity to make a claim in NCD schemes |
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204 | |
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6.3.1 Thresholds for claims when an accident occurs |
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205 | |
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6.3.2 The claims rate process in an NCD system |
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208 | |
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6.4 Reducing heterogeneity with NCD schemes |
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212 | |
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214 | |
7 Generalized Linear Models |
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221 | |
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7.1 Introduction to linear and generalized linear models |
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221 | |
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7.2 Multiple linear regression and the normal model |
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225 | |
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7.3 The structure of generalized linear models |
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230 | |
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7.3.1 Exponential families |
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232 | |
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7.3.2 Link functions and linear predictors |
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236 | |
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7.3.3 Factors and covariates |
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238 | |
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238 | |
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7.3.5 Minimally sufficient statistics |
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244 | |
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7.4 Model selection and deviance |
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245 | |
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7.4.1 Deviance and the saturated model |
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245 | |
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7.4.2 Comparing models with deviance |
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248 | |
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7.4.3 Residual analysis for generalized linear models |
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252 | |
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258 | |
8 Decision and Game Theory |
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265 | |
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265 | |
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267 | |
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8.2.1 Zero-sum two-person games |
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268 | |
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8.2.2 Minimax and saddle point strategies |
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270 | |
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8.2.3 Randomized strategies |
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273 | |
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8.2.4 The Prisoner's Dilemma and Nash equilibrium in variable-sum games |
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278 | |
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8.3 Decision making and risk |
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280 | |
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8.3.1 The minimax criterion |
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283 | |
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8.3.2 The Bayes criterion |
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283 | |
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8.4 Utility and expected monetary gain |
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288 | |
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8.4.1 Rewards, prospects and utility |
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290 | |
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8.4.2 Utility and insurance |
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292 | |
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295 | |
References |
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304 | |
Appendix A Basic Probability Distributions |
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309 | |
Appendix B Some Basic Tools in Probability and Statistics |
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313 | |
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B.1 Moment generating functions |
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313 | |
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B.2 Convolutions of random variables |
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316 | |
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B.3 Conditional probability and distributions |
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317 | |
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B.3.1 The double expectation theorem and E(X) |
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319 | |
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B.3.2 The random variable V(X|Y) |
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322 | |
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B.4 Maximum likelihood estimation |
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324 | |
Appendix C An Introduction to Bayesian Statistics |
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327 | |
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327 | |
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328 | |
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C.1.2 Loss functions and Bayesian inference |
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329 | |
Appendix D Answers to Selected Problems |
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335 | |
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D.1 Claims reserving and pricing with run-off triangles |
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335 | |
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335 | |
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337 | |
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338 | |
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338 | |
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D.6 No claim discounting in motor insurance |
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340 | |
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D.7 Generalized linear models |
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340 | |
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D.8 Decision and game theory |
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341 | |
Index |
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345 | |