MODELING THE FREQUENCY OF AUTO INSURANCE CLAIMS BY MEANS OF POISSON AND NEGATIVE BINOMIAL MODELS

Mihaela David, Danut-Vasile Jemna

Abstract


Within non-life insurance pricing, an accurate evaluation of claim frequency, also known in theory as count data, represents an essential part in determining an insurance premium according to the policyholder’s degree of risk. Count regression analysis allows the identification of the risk factors and the prediction of the expected frequency of claims given the characteristics of policyholders. The aim of this paper is to verify some aspects related to the methodology of count data models and also to the risk factors used to explain the frequency of claims. In addition to the standard Poisson regression, Negative Binomial models are applied to a French auto insurance portfolio. The best model was chosen by means of the log-likelihood ratio and the information criteria. Based on this model, the profile of the policyholders with the highest degree of risk is determined.


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Keyword(s)


claim frequency, count data models, Poisson model, overdispersion, mixed Poisson models, negative binomial models, risk factors

JEL Codes


G22 - Insurance; Insurance companies; Actuarial Studies

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