Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-10T14:51:56.423Z Has data issue: false hasContentIssue false

A Simple Geometric Proof that Comonotonic Risks Have the Convex-Largest Sum

Published online by Cambridge University Press:  29 August 2014

R. Kaas
Affiliation:
Faculty of Economics and Econometrics, Dept KE, University of Amsterdam, Roetersstraat 11, 1018 WB Amsterdam, The Netherlands, E-mail: robkaas@fee.uva.nl
J. Dhaene
Affiliation:
Center for Risk and Insurance Studies, Catholic University of Leuven, Naamsestraat 69, 3000 Leuven, Belgium, E-mail: Jan.Dhaene@econ.kuleuven.ac.be
D. Vyncke
Affiliation:
Center for Risk and Insurance Studies, Catholic University of Leuven, Naamsestraat 69, 3000 Leuven, Belgium, E-mail: David.Vyncke@econ.kuleuven.ac.be
M.J. Goovaerts
Affiliation:
Center for Risk and Insurance Studies, Catholic University of Leuven, Naamsestraat 69, 3000 Leuven, Belgium, E-mail: Marc.Goovaerts@econ.kuleuven.ac.b
M. Denuit
Affiliation:
Institut de Statistique, Université Catholique de Louvain, Voie du Roman Pays 20, 1348 Louvain-la-Neuve, Belgium, E-mail: denuit@stat.ucl.ac.b
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

In the recent actuarial literature, several proofs have been given for the fact that if a random vector (X1X2, …, Xn) with given marginals has a comonotonic joint distribution, the sum X1 + X2 + … + Xn is the largest possible in convex order. In this note we give a lucid proof of this fact, based on a geometric interpretation of the support of the comonotonic distribution.

Type
Articles
Copyright
Copyright © International Actuarial Association 2002

References

Bäuerle, N. and Müller, A. (1998) “Modeling and comparing dependencies in multivariate risk portfolios”, ASTIN Bulletin 28, 5976.CrossRefGoogle Scholar
Dhaene, J. and Denuit, M. (1999) “The safest dependency structure among risks”, Insurance: Mathematics & Economics 25, 1121.Google Scholar
Dhaene, J. and Goovaerts, M. (1996) “Dependency of risks and stop-loss order”, ASTIN Bulletin 26, 201212.CrossRefGoogle Scholar
Dhaene, J. and Goovaerts, M.J. (1997) “On the dependency of risks in the individual life model”, Insurance: Mathematics & Economics 19, 243253.Google Scholar
Dhaene, J., Wang, S., Young, V. and Goovaerts, M.J. (2000) “Comonotonicity and maximal stop-loss premiums”, Bulletin of the Swiss Association of Actuaries, 2000(2), 99113.Google Scholar
Fréchet, M. (1951) “Sur les tableaux de corrélation dont les marges sont données”, Ann. Univ. Lyon Sect. A, Series 3, 14, 5377.Google Scholar
Goovaerts, M.J. and Dhaene, J. (1999) “Supermodular ordering and stochastic annuities”, Insurance: Mathematics & Economics, 24(3), 281290.Google Scholar
Goovaerts, M.J., Dhaene, J. and De Schepper, A. (2000) “Stochastic Upper Bounds for Present Value Functions”, Journal of Risk and Insurance Theory, 67.1, 114.CrossRefGoogle Scholar
Goovaerts, M.J. and Kaas, R. (2002) “Some problems in actuarial finance involving sums of dependent risks”, Statistica Neerlandica, to appear.Google Scholar
Goovaerts, M.J., Kaas, R., Van Heerwaarden, A.E. and Bauwelinckx, T. (1990) “Effective Actuarial Methods”. North-Holland, Amsterdam.Google Scholar
Goovaerts, M.J. and Redant, R. (1999) “On the distribution of IBNR reserves”, Insurance: Mathematics & Economics 25, 19.Google Scholar
Hoeffding, W. (1940) “Masstabinvariante Korrelationstheorie”, Schriften des mathematischen Instituts und des Instituts für angewandte Mathematik der Universität Berlin 5, 179233.Google Scholar
Kaas, R., Van Heerwaarden, A.E. and Goovaerts, M.J. (1994) “Ordering of actuarial risks”, Institute for Actuarial Science and Econometrics, University of Amsterdam, Amsterdam.Google Scholar
Kaas, R., Dhaene, J. and Goovaerts, M.J. (2000). “Upper and lower bounds for sums of random variables”, Insurance: Mathematics & Economics 23, 151168.Google Scholar
Kaas, R., Goovaerts, M.J., Dhaene, J. and Denuit, M. (2001). “Modern Actuarial Risk Theory”, Kluwer, Dordrecht.Google Scholar
Meilijson, I. and Nadas, A. (1979) “Convex majorization with an application to the length of critical paths”, Journal of Applied Probability, 16, 671677.CrossRefGoogle Scholar
Müller, A. (1997) “Stop-loss order for portfolios of dependent risks”, Insurance: Mathematics & Economics 21, 219223.Google Scholar
Roëll, A. (1987) “Risk aversion in Quiggin and Yaari‘s rank-order model of choice under uncertainty”, The Economic Journal 97 (Conference 1987), 143159.CrossRefGoogle Scholar
Schmeidler, D. (1986) “Integral representation without additivity”, Proceedings of the American Mathematical Society 97, 255261.CrossRefGoogle Scholar
Shared, M. and Shanthikumar, J.G. (1994) Stochastic orders and their applications. Probability and Mathematical Statistics, Academic Press.Google Scholar
Wang, S. and Dhaene, J. (1998) “Comonotonicity, correlation order and stop-loss premiums”, Insurance: Mathematics & Economics 22, 235243.Google Scholar
Wang, S. and Young, V. (1998) “Ordering risks: expected utility versus Yaari's dual theory of choice under risk”. Insurance: Mathematics & Economics 22, 145162.Google Scholar
Yaari, M.E. (1987) “The dual theory of choice under risk”, Econometrica 55, 95115.CrossRefGoogle Scholar