Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-22T15:10:18.428Z Has data issue: false hasContentIssue false

FORECASTING MULTIPLE FUNCTIONAL TIME SERIES IN A GROUP STRUCTURE: AN APPLICATION TO MORTALITY

Published online by Cambridge University Press:  18 February 2020

Han Lin Shang*
Affiliation:
Research School of Finance, Actuarial Studies and Statistics, Australian National University, Canberra, ACT2601, Australia, E-Mail: [email protected]
Steven Haberman
Affiliation:
Cass Business School, City, University of London, LondonEC1V 0HB, UK, E-Mail: [email protected]

Abstract

When modelling subnational mortality rates, we should consider three features: (1) how to incorporate any possible correlation among subpopulations to potentially improve forecast accuracy through multi-population joint modelling; (2) how to reconcile subnational mortality forecasts so that they aggregate adequately across various levels of a group structure; (3) among the forecast reconciliation methods, how to combine their forecasts to achieve improved forecast accuracy. To address these issues, we introduce an extension of grouped univariate functional time-series method. We first consider a multivariate functional time-series method to jointly forecast multiple related series. We then evaluate the impact and benefit of using forecast combinations among the forecast reconciliation methods. Using the Japanese regional age-specific mortality rates, we investigate 1–15-step-ahead point and interval forecast accuracies of our proposed extension and make recommendations.

Type
Research Article
Copyright
© Astin Bulletin 2020

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bates, J.M. and Granger, C.W.J. (1969) The combination of forecasts. Operational Research Quarterly, 20(4), 451468.CrossRefGoogle Scholar
Cannon, E. and Tonks, I. (2008) Annuity Markets. Oxford: Oxford University Press.CrossRefGoogle Scholar
Dickson, D.C.M., Hardy, M.R. and Waters, H.R. (2009) Actuarial Mathematics for Life Contingent Risks. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Fung, M.C., Peters, G.W. and Shevchenko, P.V. (2017) A unified approach to mortality modelling using state-space framework: Characterisation, identification, estimation and forecasting. Annals of Actuarial Science, 11(2), 343389.CrossRefGoogle Scholar
Gaba, A., Tsetlin, I. and Winkler, R.L. (2017) Combining interval forecasts. Decision Analysis, 14(1), 174.CrossRefGoogle Scholar
Gaille, S.A. and Sherris, M. (2015) Causes-of-death mortality: What do we know on their dependence?. North American Actuarial Journal, 19(2), 116128.Google Scholar
Gneiting, T. and Raftery, A.E. (2007) Strictly proper scoring rules, prediction and estimation. Journal of the American Statistical Association, 102(477), 359–378.CrossRefGoogle Scholar
Hatzopoulos, P. and Haberman, S. (2013) Common mortality modelling and coherent forecasts - an empirical analysis of worldwide mortality data. Insurance: Mathematics and Economics, 52(2), 320337.Google Scholar
Hyndman, R.J., Ahmed, R.A., Athanasopoulos, G. and Shang, H. L. (2011) Optimal combination forecasts for hierarchical time series. Computational Statistics and Data Analysis, 55(9), 25792589.CrossRefGoogle Scholar
Hyndman, R.J. and Khandakar, Y. (2008) Automatic time series forecasting: The forecast package for R. Journal of Statistical Software, 27(3).CrossRefGoogle Scholar
Hyndman, R.J. and Ullah, M.S. (2007) Robust forecasting of mortality and fertility rates: A functional data approach. Computational Statistics & Data Analysis, 51(10), 49424956.CrossRefGoogle Scholar
Japanese Mortality Database (2019) National Institute of Population and Social Security Research. Available at http://www.ipss.go.jp/p-toukei/JMD/index-en.html. data downloaded on July 18, 2018.Google Scholar
Lee, R.D. and Carter, L.R. (1992) Modeling and forecasting U.S. mortality. Journal of the American Statistical Association, 87(419), 659671.Google Scholar
Li, H., Li, H., Lu, Y. and Panagiotelis, A. (2019) A forecast reconciliation approach to cause-of-death mortality modeling. Insurance: Mathematics and Economics, 86, 122133.Google 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.CrossRefGoogle Scholar
Olivieri, A. and Pitacco, E. (2016) Frailty and risk classification for life annuity portfolios. Risks, 4(4), 39.Google Scholar
O’Meara, T. and Bruhn, A. (2013) Compulsory Annuitisation: A policy option for Australia? Australasian Accounting Business and Finance Journal, 7(3), 530.CrossRefGoogle Scholar
Richman, R. and Wüthrich, M.V. (2020a, in press) A neural network extension of the Lee–Carter model to multiple populations. Annals of Actuarial Science.CrossRefGoogle Scholar
Richman, R. and Wüthrich, M.V. (2020b), Lee and Carter go machine learning: Recurrent neural networks. Working paper, ETH Zurich. Available at SSRN: https://papers.ssrn.com/abstract=3441030.CrossRefGoogle Scholar
Shang, H.L. (2020, in press) Dynamic principal component regression for forecasting functional time series in a group structure. Scandinavian Actuarial Journal.CrossRefGoogle Scholar
Shang, H.L., Booth, H. and Hyndman, R.J. (2011) Point and interval forecasts of mortality rates and life expectancy: A comparison of ten principal component methods. Demographic Research, 25(5), 173214.CrossRefGoogle Scholar
Shang, H.L. and Haberman, S. (2017) Grouped multivariate and functional time series forecasting: An application to annuity pricing. Insurance: Mathematics and Economics, 75, 166179.Google Scholar
Shang, H.L. and Hyndman, R.J. (2017) Grouped functional time series forecasting: An application to age-specific mortality rates. Journal of Computational and Graphical Statistics, 26(2), 330343.CrossRefGoogle Scholar
Villegas, A.M. and Haberman, S. (2014) On the modeling and forecasting of socioeconomic mortality differentials: An application to deprivation and mortality in England. North American Actuarial Journal, 18(1), 168193.CrossRefGoogle Scholar
Wickramasuriya, S.L., Athanasopoulos, G. and Hyndman, R.J. (2019) Optimal forecast reconciliation for hierarchical and grouped time series through trace minimization. Journal of the American Statistical Association: Theory and Methods, 114(526), 804819.CrossRefGoogle Scholar
Yaari, M.E. (1965) Uncertain lifetime, life insurance, and the theory of the consumer. The Review of Economic Studies, 32(2), 137150.CrossRefGoogle Scholar
Supplementary material: File

Shang and Haberman supplementary material

Shang and Haberman supplementary material 1

Download Shang and Haberman supplementary material(File)
File 5 MB
Supplementary material: File

Shang and Haberman supplementary material

Shang and Haberman supplementary material 2

Download Shang and Haberman supplementary material(File)
File 2.8 MB