We examine the evolutionary basis for risk aversion with respect to aggregate risk. We study populations in which agents face choices between aggregate risk and idiosyncratic 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 taking 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：我们研究了总风险规避风险的演变基础。我们研究了总风险规避风险的演变基础。我们研究了总风险和特异性风险之间各种物剂面临选择的人群。我们发现,使长期增长率最大化的选择是由不同人群引发的,在人群中,最小和最不愿意风险的物剂分别对承担总风险和获得其线性与和谐性平均值之间持漠不关心态度。此外,通过简单分布,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均匀分布,可以诱发大约最佳的行为。