Evolution and Preference for Local Risk

Heller, Yuval and Robson, Arthur (2019): Evolution and Preference for Local Risk.

Abstract

Our understanding of risk preferences can be sharpened by considering their evolutionary basis. Recently, Robatto and Szentes (2017) found that both aggregate risk and idiosyncratic risk generate the same growth rate in a continuous time setting. We introduce a new source of risk, which is correlated between agents in the same location, but is uncorrelated between agents in different locations. We show that this local risk induces a strictly higher growth rate. This shows that interdependence of risk and population structure have important implications in a continuous-time setting, and that natural selection induces individuals to prefer local risk.

• Item Type: MPRA Paper
• Language: English
• Keywords: Risk preferences, evolution, risk interdependence, long-run growth rate.
• Subjects: D - Microeconomics > D8 - Information, Knowledge, and Uncertainty > D81 - Criteria for Decision-Making under Risk and Uncertainty; D - Microeconomics > D9 - Intertemporal Choice > D91 - Intertemporal Household Choice ; Life Cycle Models and Saving

References

Burkey, Tormod Vaaland. 1999. Extinction in fragmented habitats predicted from stochastic birth–death processes with density dependence. Journal of Theoretical Biology, 199(4),395–406.

Duffie, Darrell, & Sun, Yeneng. 2012. The exact law of large numbers for independent random matching. Journal of Economic Theory, 147(3), 1105–1139.

Heller, Yuval. 2014. Overconfidence and diversification. American Economic Journal: Microeconomics, 6(1), 134–153.

Lehmann, Laurent, & Balloux, François. 2007. Natural selection on fecundity variance in subdivided populations: Kin selection meets bet hedging. Genetics, 176(1), 361–377.

Lewontin, Richard C., & Cohen, Daniel. 1969. On population growth in a randomly varying environment. Proceedings of the National Academy of Sciences, 62(4), 1056–1060.

McNamara, John M. 1995. Implicit frequency dependence and kin selection in fluctuating environments. Evolutionary Ecology, 9(2), 185–203.

McNamara, John M., & Dall, Sasha R. X. 2011. The evolution of unconditional strategies via the multiplier effect. Ecology Letters, 14(3), 237–243.

Robatto, Roberto, & Szentes, Balázs. 2017. On the biological foundation of risk preferences. Journal of Economic Theory, 172, 410–422.

Robson, Arthur J. 1996. A biological basis for expected and non-expected utility. Journal of Economic Theory, 68(2), 397–424.

Robson, Arthur J., & Samuelson, Larry. 2009. The evolution of time preference with aggregate uncertainty. American Economic Review, 99(5), 1925–1953.

Robson, Arthur J, & Samuelson, Larry. 2011. The evolutionary foundations of preferences. Pages 221–310 of: Benhabib, Jess, Bisin, Alberto, & Jackson, Matthew (eds), The Handbook of Social Economics, vol. 1. Elsevier.

Robson, Arthur J., & Samuelson, Larry. 2019. Evolved attitudes to idiosyncratic and aggregate risk in age-structured populations. Journal of Eocnomic Theory, 181, 44–81.

Smith, James N. M., & Hellmann, Jessica J. 2002. Population persistence in fragmented landscapes. Trends in Ecology & Evolution, 17(9), 397–399.