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SMOOTHING POISSON COMMON FACTOR MODEL FOR PROJECTING MORTALITY JOINTLY FOR BOTH SEXES

Published online by Cambridge University Press:  09 January 2018

David Pitt
Affiliation:
Department of Applied Finance and Actuarial Studies, Macquarie University, NSW 2109, Australia E-Mail: david.pitt@mq.edu.au
Jackie Li*
Affiliation:
Department of Applied Finance and Actuarial Studies, Macquarie University, NSW 2109, Australia
Tian Kang Lim
Affiliation:
Department of Applied Finance and Actuarial Studies, Macquarie University, NSW 2109, Australia E-Mail: tian.lim@mq.edu.au

Abstract

We consider a modification to the Poisson common factor model and utilise a generalised linear model (GLM) framework that incorporates a smoothing process and a set of linear constraints. We extend the standard GLM model structure to adopt Lagrange methods and P-splines such that smoothing and constraints are applied simultaneously as the parameters are estimated. Our results on Australian, Canadian and Norwegian data show that this modification results in an improvement in mortality projection in terms of producing more accurate forecasts in the out-of-sample testing. At the same time, projected male-to-female ratio of death rates at each age converges to a constant and the residuals of the models are sufficiently random, indicating that the use of smoothing does not adversely affect the fit of the model. Further, the irregular patterns in the estimates of the age-specific parameters are moderated as a result of smoothing and this model can be used to produce more regular projected life tables for pricing purposes.

Type
Research Article
Copyright
Copyright © Astin Bulletin 2018 

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References

Booth, H., Hyndman, R., Tickle, L. and de Jong, P. (2006) Lee-Carter mortality forecasting: a multi-country comparison of variants and extensions. Demographic Research, 15 (9), 289310.Google Scholar
Booth, H., Maindonald, J. and Smith, L. (2001) Age-time interactions in mortality projection: applying Lee-Carter to Australia. Research School of Social Sciences, Working papers in Demography, Canberra, August 2002.Google Scholar
Booth, H., Maindonald, J. and Smith, L. (2002) Applying Lee-Carter under conditions of variable mortality decline. Population Studies, 56 (3), 325336.Google Scholar
Booth, H. and Tickle, L. (2008) Mortality modelling and forecasting: a review of methods. Annals of Actuarial Science, 3 (1–2), 343.Google Scholar
Brouhns, N., Denuit, M. and Van Keilegom, I. (2005) Bootstrapping the Poisson log-bilinear model for mortality forecasting. Scandinavian Actuarial Journal, 3, 212224.Google Scholar
Brouhns, N., Denuit, M. and Vermunt, J. (2002) A Poisson log-bilinear regression approach to the construction of projected lifetables. Insurance: Mathematics and Economics, 31 (3), 373393.Google Scholar
Cairns, A.J.G., Blake, D., Dowd, K., Coughlan, G.D. and Khalaf-Allah, M. (2011) Bayesian stochastic mortality modelling for two populations. ASTIN Bulletin, 41 (1), 2959.Google Scholar
Chan, W.S., Li, J.S.H. and Li, J. (2014) The CBD mortality indexes: modeling and applications. North American Actuarial Journal, 18 (1), 3558.Google Scholar
Currie, I. (2013) Smoothing constrained generalized linear models with an application to the Lee-Carter model. Statistical Modelling, 13 (1), 6993.CrossRefGoogle Scholar
Currie, I., Durban, M. and Eilers, P. (2004) Smoothing and forecasting mortality rates. Statistical Modelling, 4 (4), 279298.CrossRefGoogle Scholar
Currie, I. (2016) On fitting generalized linear and non-linear models of mortality. Scandinavian Actuarial Journal, 4, 356383.CrossRefGoogle Scholar
De Jong, P. and Tickle, L. (2006) Extending Lee-Carter mortality forecasting. Mathematical Population Studies, 13 (1), 118.CrossRefGoogle Scholar
Delwarde, A., Denuit, M. and Eilers, P. (2007) Smoothing the Lee-Carter and Poisson log-bilinear models for mortality forecasting: a penalized log-likelihood approach. Statistical Modelling, 7 (1), 2948.CrossRefGoogle Scholar
Eilers, P. and Marx, B. (1996) Flexible smoothing with B-splines and penalties. Statistical Science, 11 (2), 89121.Google Scholar
Eilers, P. and Marx, B. (2010) Splines, knots, and penalties. Wiley Interdisciplinary Reviews: Computational Statistics, 2 (6), 637653.Google Scholar
Hastie, T. and Tibshirani, R. (1990) Generalized Additive Models. London: Chapman and HallGoogle Scholar
Hyndman, R.J., Booth, H. and Yasmeen, F. (2013) Coherent mortality forecasting: the product-ratio method with functional time series models. Demography 50 (1), 261283.CrossRefGoogle ScholarPubMed
Hyndman, R. and Dokumentov, A. (2013) Two-dimensional smoothing of mortality rates. Working paper 26/13, November 2013.Google Scholar
Hyndman, R. and Shahid Ullah, M. (2007) Robust forecasting of mortality and fertility rates: A functional data approach. Computational Statistics & Data Analysis, 51 (10), 49424956.Google Scholar
Jarner, S. and Kryger, E. (2011) Modelling adult mortality in small populations: the SAINT model. ASTIN Bulletin, 41 (2), 377418.Google Scholar
Kogure, A., Li, J. and Kamiya, S. (2014) A Bayesian multivariate risk-neutral method for pricing reverse mortgages. North American Actuarial Journal, 18 (1), 242257.CrossRefGoogle Scholar
Koissi, M. and Shapiro, A. (2006) Fuzzy formulation of the Lee-Carter model for mortality forecasting. Insurance: Mathematics and Economics, 39 (3), 287309.Google Scholar
Koissi, M., Shapiro, A. and Högnäs, G. (2006) Evaluating and extending the Lee-Carter model for mortality forecasting: Bootstrap confidence interval. Insurance: Mathematics and Economics, 38 (1), 120.Google Scholar
Lee, R. and Carter, L. (1992) Modelling and forecasting U.S. mortality. Journal of the American Statistical Association, 87 (419), 659671.Google Scholar
Li, J. (2010) Projections of New Zealand mortality using the Lee-Carter model and its augmented common factor extension. New Zealand Population Review, 36, 2753.Google Scholar
Li, J. (2013) A Poisson common factor model for projecting mortality and life expectancy jointly for females and males. Population Studies, 67 (1), 111126.CrossRefGoogle ScholarPubMed
Li, J. (2014a) A quantitative comparison of simulation strategies for mortality projection. Annals of Actuarial Science, 8 (2), 281297.Google Scholar
Li, J. (2014b) An application of MCMC simulation in mortality projection for populations with limited data. Demographic Research, 30 (1), 148.CrossRefGoogle Scholar
Li, N. and Lee, R. (2005) Coherent mortality forecasts for a group of populations: an extension of the Lee-Carter method. Demography, 42 (3), 575594.Google Scholar
McCullagh, P. and Nelder, J. (1989) Generalized Linear Models. 2nd ed. London: Chapman & HallGoogle Scholar
Parr, N., Li, J. and Tickle, L. (2016) A cost of living longer: projections of the effects of prospective mortality improvement on economic support ratios for 14 advanced economies. Population Studies, 70 (2), 181200Google Scholar
Renshaw, A. and Haberman, S. (2003) Lee-Carter mortality forecasting: a parallel generalized linear modelling approach for England and Wales mortality projections. Applied Statistics, 52 (1), 119137.Google Scholar
Renshaw, A. and Haberman, S. (2006) A cohort-based extension to the Lee-Carter model for mortality reduction factors. Insurance: Mathematics and Economics, 38 (3), 556570.Google Scholar
Renshaw, A.E. and Haberman, S. (2008) On simulation-based approaches to risk measurement in mortality with specific reference to Poisson Lee-Carter modelling. Insurance: Mathematics and Economics, 42 (2), 797816.Google Scholar
Renshaw, A., Haberman, S. and Hatzopoulos, P. (1996) The modelling of recent mortality trends in United Kingdom male assured lives. British Actuarial Journal, 2 (2), 449477.Google Scholar
Tan, C.I., Li, J., Li, J.S.H. and Balasooriya, U. (2014) Parametric mortality indexes: from index construction to hedging strategies. Insurance: Mathematics and Economics, 59, 285299.Google Scholar
Tuljapurkar, S., Li, N. and Boe, C. (2000) A universal pattern of mortality decline in the G7 countries. Nature, 405, 789792.Google Scholar
Wilmoth, J.R. (Dec. 1993) Computational methods for fitting and extrapolating the Lee-Carter model of mortality change. Technical Report, University of California, Berkeley. U.S.A.Google Scholar
Wood, S.N. (2006) Generalized Additive Models: An Introduction with R. London: Chapman & Hall/CRC.Google Scholar
Yang, B., Li, J. and Balasooriya, U. (2016) Cohort extensions of the Poisson common factor model for modelling both genders jointly. Scandinavian Actuarial Journal, 2, 93112.Google Scholar