We examine the evolutionary basis for risk aversion with respect to aggregate risk. We study populations in which agents face choices between alternatives with different levels of aggregate risk. We show that the choices that maximize the long-run growth rate are induced by a heterogeneous population in which the least and most risk-averse agents are indifferent between facing an aggregate risk and obtaining its linear and harmonic mean for sure, respectively. Moreover, approximately optimal behavior can be induced by a simple distribution according to which all agents have constant relative risk aversion, and the coefficient of relative risk aversion is uniformly distributed between zero and two.

翻译：我们研究总风险规避风险的演变基础。我们研究的是,各种物剂在不同风险水平的替代品之间面临选择的人群。我们发现,使长期增长率最大化的选择是由不同人群引起的,其中最小和最不愿意风险的物剂分别对面临总风险和获得其线性与合力的肯定值之间漠不关心。此外,通过简单的分布,所有物剂都具有持续的相对风险规避风险,相对风险规避系数在零和二之间统一分布,可以诱发大约最佳的行为。