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Full Credibility with Generalized Linear and Mixed Models

Published online by Cambridge University Press:  09 August 2013

Jun Zhou
Affiliation:
Research and Development, Aviva Canada Inc., 8th floor, 630 René Lévesque W., Montreal, QC, H3B 1S6, Canada, E-mail: [email protected]

Abstract

Generalized linear models (GLMs) are gaining popularity as a statistical analysis method for insurance data. For segmented portfolios, as in car insurance, the question of credibility arises naturally; how many observations are needed in a risk class before the GLM estimators can be considered credible? In this paper we study the limited fluctuations credibility of the GLM estimators as well as in the extended case of generalized linear mixed model (GLMMs). We show how credibility depends on the sample size, the distribution of covariates and the link function. This provides a mechanism to obtain confidence intervals for the GLM and GLMM estimators.

Type
Research Article
Copyright
Copyright © International Actuarial Association 2009

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Footnotes

* This research was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant 36860–06.

References

Aitkin, M., Anderson, D., Francis, B. and Hinde, J. (1989) Statistical Modelling in GLIM. Oxford Science Publications, Oxford.Google Scholar
Antonio, K. and Beirlant, J. (2007) Actuarial statistics with generalized linear mixed models. Insurance: Mathematics and Economics, 40(1), 5876.Google Scholar
Bailey, A. (1950) Credibility procedures, Laplace's generalization of Bayes' rule and the combination of collateral knowledge with observed data. Proc. of the Casualty Actuarial Society, 37, 723 (with discussions, 94-115).Google Scholar
Bühlmann, H. (1967) Experience rating and credibility. ASTIN Bulletin, 4(3), 199207.CrossRefGoogle Scholar
Bühlmann, H. (1969) Experience rating and credibility. ASTIN Bulletin, 5(2), 157165.Google Scholar
Bühlmann, H. and Straub, E. (1970) Glaubwürdigkeit für Schadensätze. Bulletin of the Swiss Association of Actuaries, 111133.Google Scholar
Cordeiro, G.M. and McCullagh, P. (1991) Bias correction in generalized linear models. Journal of the Royal Statistical Society, B 53(3), 629643.Google Scholar
Demindenko, E. (2004) Mixed Models: Theory and Applications. Hoboken, New Jersey.Google Scholar
Dobson, A. (1990) An Introduction to Generalized Linear Models. Chapman and Hall, London.CrossRefGoogle Scholar
Fahrmeir, L. and Kaufmann, H. (2003) Consistency and asymptotic normalty of the maximum likelihood estimator in generalized linear models. The Annuals of Statistics, 13(1), 342368.Google Scholar
Haberman, S. and Renshaw, A.E. (1996) Generalized linear models and actuarial science. The Statistician, 45(4), 407436.Google Scholar
Hachemeister, C.A. (1975) Credibility for regression models with application to trend. In Credibility, Theory and Application. Academic Press, New York, 129163.Google Scholar
Harbin, J.W. and Hilbe, J.M. (2007) Generalized Linear Models and Extensions, 2nd Edition. Chapman and Hall/CRC, Boca Raton.Google Scholar
Jewell, W.S. (1975) The use of collateral data in credibility theory: A hierarchical model. Giornale dell'Instituto Italiano degli Attuari, 38, 116.Google Scholar
Lee, Y., Nelder, J.A. and Pawitan, Y. (2007) Generalized Linear Models With Random Effects. Chapman and Hall/CRC, Boca Raton.Google Scholar
Liang, K.Y. and Zeger, S.L. (1986) Longitudinal data analysis using generalized linear models. Biometrika, 73(1), 1322.CrossRefGoogle Scholar
McCullagh, P. and Nelder, J.A. (1989) Generalized Linear Models. Chapman and Hall, New-York.Google Scholar
McCulloch, C.E. and Searle, S.R. (2001) Generalized, Linear and Mixed Models. Wiley, New York.Google Scholar
Mowbray, A.H. (1914) How extensive a payroll exposure is necessary to give a dependable pure premium. Proc. of the Casualty Actuarial Society, 1, 2430.Google Scholar
Nelder, J.A. and Verrall, R.J. (1997) Credibility theory and generalized linear models. ASTIN Bulletin, 27(1), 7182.Google Scholar
SAS Technical Report P-243 (1993) SAS/STAT Software: The GENMOD Procedure, Release 6.09, SAS Institute Inc., Cary, NC.Google Scholar
SAS/STAT Software (2006) GLIMMIX Procedure, Release 9.1, June 2006, SAS Institute Inc., Cary, NC.Google Scholar
Schabenberger, O. and Gregoire, T.G. (1996) Population-averaged and subject-specific approaches for clustered categorical data. Journal of Statistical Computation and Simulation, 54, 231253.CrossRefGoogle Scholar
Schmitter, H. (2004) The sample size needed for the calculation of a GLM tariff. ASTIN Bulletin, 34(1), 249262.Google Scholar
Whitney, A.W. (1918) The theory of experience rating. Proc. of the Casualty Actuarial Society, 4, 274292.Google Scholar
Wolfinger, R. and O'Connell, M. (1993) Generalized linear mixed models: a pseudo-likelihood approach. Journal of Statistical Computation and Simulation, 4, 233243.Google Scholar