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Asymmetry in mortality volatility and its implications on index-based longevity hedging

Published online by Cambridge University Press:  05 May 2020

Kenneth Q. Zhou
Affiliation:
Department of Statistics and Actuarial Science, University of Waterloo, Ontario, Canada School of Mathematical and Statistical Sciences, Arizona State University, Tempe, AZ, USA
Johnny Siu-Hang Li*
Affiliation:
Department of Statistics and Actuarial Science, University of Waterloo, Ontario, Canada Department of Economics, University of Melbourne, Melbourne, Australia
*
* Corresponding author. E-mail: [email protected]

Abstract

Mortality volatility is crucially important to many aspects of index-based longevity hedging, including instrument pricing, hedge calibration and hedge performance evaluation. This paper sets out to develop a deeper understanding of mortality volatility and its implications on index-based longevity hedging. First, we study the potential asymmetry in mortality volatility by considering a wide range of generalised autoregressive conditional heteroskedasticity (GARCH)-type models that permit the volatility of mortality improvement to respond differently to positive and negative mortality shocks. We then investigate how the asymmetry of mortality volatility may impact index-based longevity hedging solutions by developing an extended longevity Greeks framework, which encompasses longevity Greeks for a wider range of GARCH-type models, an improved version of longevity vega, and a new longevity Greek known as “dynamic Delta”. Our theoretical work is complemented by two real-data illustrations, the results of which suggest that the effectiveness of an index-based longevity hedge could be significantly impaired if the asymmetry in mortality volatility is not taken into account when the hedge is calibrated.

Type
Paper
Copyright
© Institute and Faculty of Actuaries 2020

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References

Badescu, A., Elliott, R.J. & Ortega, J.-P. (2014). Quadratic hedging schemes for non-Gaussian GARCH models. Journal of Economic Dynamics and Control, 42, 1332.CrossRefGoogle Scholar
Bekaert, G. & Wu, G. (2000). Asymmetric volatility and risk in equity markets. Review of Financial Studies, 13(1), 142.CrossRefGoogle Scholar
Biffis, E. & Blake, D. (2014). Keeping some skin in the game: how to start a capital market in longevity risk transfers. North American Actuarial Journal, 18(1), 1421.10.1080/10920277.2013.872552CrossRefGoogle Scholar
Blake, D., Cairns, A., Coughlan, G., Dowd, K. & Macminn, R. (2013). The new life market. Journal of Risk and Insurance, 80(3), 501557.10.1111/j.1539-6975.2012.01514.xCrossRefGoogle Scholar
Brouhns, N., Denuit, M. & Vermunt, J.K. (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. (2011). Modelling and management of longevity risk: approximations to survivor functions and dynamic hedging. Insurance: Mathematics and Economics, 49(3), 438453.Google Scholar
Cairns, A.J. (2013). Robust hedging of longevity risk. Journal of Risk and Insurance, 80(3), 621648.CrossRefGoogle Scholar
Cairns, A.J., Blake, D. & Dowd, K. (2006). A two-factor model for stochastic mortality with parameter uncertainty: theory and calibration. Journal of Risk and Insurance, 73(4), 687718.CrossRefGoogle Scholar
Cairns, A.J., Dowd, K., Blake, D. & Coughlan, G.D. (2014). Longevity hedge effectiveness: a decomposition. Quantitative Finance, 14(2), 217235.CrossRefGoogle Scholar
Campbell, J.Y. & Hentschel, L. (1992). No news is good news: an asymmetric model of changing volatility in stock returns. Journal of Financial Economics, 31(3), 281318.CrossRefGoogle Scholar
Chai, C.M.H., Siu, T.K., Zhou, X., Hui, M., Chai, C.M.H., Kuen, T. & Xian, S. (2013). A double-exponential GARCH model for stochastic mortality. European Actuarial Journal, 3(2), 385406.CrossRefGoogle Scholar
Chen, H., MacMinn, R. & Sun, T. (2015). Multi-population mortality models: a factor copula approach. Insurance: Mathematics and Economics, 63, 135146.Google Scholar
Coughlan, G., Epstein, D., Sinha, A. & Honig, P. (2007). q-Forwards: Derivatives for Transferring Longevity and Mortality Risks. JPMorgan Pension Advisory Group, London.Google Scholar
Coughlan, G.D., Khalaf-Allah, M., Ye, Y., Kumar, S., Cairns, A.J., Blake, D. & Dowd, K. (2011). Longevity hedging 101. North American Actuarial Journal, 15(2), 150176.10.1080/10920277.2011.10597615CrossRefGoogle Scholar
De Rosa, C., Luciano, E. & Regis, L. (2017). Basis risk in static versus dynamic longevity-risk hedging. Scandinavian Actuarial Journal, 2017(4), 343365.CrossRefGoogle Scholar
Duan, J.-C. (2009). The GARCH Option Pricing Model Theory, Numerical Methods, Evidence and Applications. Risk Management Institute and Department of Finance National U of Singapore.Google Scholar
Engle, R.F. & Ng, V.K. (1993). Measuring and testing the impact of news on volatility. The Journal of Finance, 48(5), 1749.CrossRefGoogle Scholar
Engle, R.F. & Rosenberg, J.V. (1995). GARCH gamma. Journal of Derivarives, 2(4), 4759.CrossRefGoogle Scholar
Fung, M.C., Peters, G.W. & Shevchenko, P.V. (2017). A unified approach to mortality modelling using state-space framework: characterisation, identification, estimation and forecasting. Annals of Actuarial Science, 11(02), 343389.10.1017/S1748499517000069CrossRefGoogle Scholar
Gao, Q. & Hu, C. (2009). Dynamic mortality factor model with conditional heteroskedasticity. Insurance: Mathematics and Economics, 45(3), 410423.Google Scholar
Giacometti, R., Bertocchi, M., Rachev, S.T. & Fabozzi, F.J. (2012). A comparison of the Lee-Carter model and AR-ARCH model for forecasting mortality rates. Insurance: Mathematics and Economics, 50(1), 8593.Google Scholar
Glosten, L.R., Jagannathan, R. & Runkle, D.E. (1993). On the relation between the expected value and the volatility of the nominal excess return on stocks. The Journal of Finance, 48(5), 17791801.CrossRefGoogle Scholar
Koutmos, G. & Booth, G. (1995). Asymmetric volatility transmission in international stock markets. Journal of International Money and Finance, 14(6), 747762.CrossRefGoogle Scholar
Lee, R. & Miller, T. (2001). Evaluating the performance of the Lee-Carter method for forecasting mortality. Demography, 38(4), 537549.10.1353/dem.2001.0036CrossRefGoogle ScholarPubMed
Li, J.S.-H. & Hardy, M.R. (2011). Measuring basis risk in longevity hedges. North American Actuarial Journal, 15(2), 177200.CrossRefGoogle Scholar
Lin, T., Wang, C.W. & Tsai, C.C.-L. (2015). Age-specific copula-AR-GARCH mortality models. Insurance: Mathematics and Economics, 61, 110124.Google Scholar
Liu, Y. & Li, J.S.-H. (2016). The locally linear Cairns-Blake-Dowd model: a note on delta-nuga hedging of longevity risk. ASTIN Bulletin, 47(1), 79151.CrossRefGoogle Scholar
Luciano, E. & Regis, L. (2014). Efficient versus inefficient hedging strategies in the presence of financial and longevity (value at) risk. Insurance: Mathematics and Economics, 55(1), 6877.Google Scholar
Luciano, E., Regis, L. & Vigna, E. (2012). Delta-gamma hedging of mortality and interest rate risk. Insurance: Mathematics and Economics, 50(3), 402412.Google Scholar
Luciano, E., Regis, L. & Vigna, E. (2017). Single- and cross-generation natural hedging of longevity and financial risk. Journal of Risk and Insurance, 84(3), 961986.CrossRefGoogle Scholar
Michaelson, A. & Mulholland, J. (2014). Strategy for increasing the global capacity for longevity risk transfer: developing transactions that attract capital markets investors. The Journal of Alternative Investments, 17(1), 1827.CrossRefGoogle Scholar
Nelson, D.B. (1991). Conditional heteroskedasticity in asset returns: a new approach. Econometrica, 59(2), 347.CrossRefGoogle Scholar
Wang, Z. & Li, J.S.-H. (2016). A DCC-GARCH multi-population mortality model and its applications to pricing catastrophic mortality bonds. Finance Research Letters, 16, 103111.CrossRefGoogle Scholar
Zakoian, J.-M. (1994). Threshold heteroskedastic models. Journal of Economic Dynamics and Control, 18(5), 931955.CrossRefGoogle Scholar
Zhou, K.Q. & Li, J.S.-H. (2017). Dynamic longevity hedging in the presence of population basis risk: a feasibility analysis from technical and economic perspectives. The Journal of Risk and Insurance, 84(S1), 417437.CrossRefGoogle Scholar
Zhou, K.Q. & Li, J.S.-H. (2019a). Longevity Greeks: what do insurers and capital market investors need to know? North Americal Actuarial Journal, DOI: 10.1080/10920277.2019.1650283.CrossRefGoogle Scholar
Zhou, K.Q. & Li, J.S.-H. (2019b). Delta-hedging longevity risk under the M7–M5 model: the impact of cohort effect uncertainty and population basis risk. Insurance: Mathematics and Economics, 84, 121.Google Scholar