First-Order and Second-Order Ambiguity Aversion
定义了不确定性决策中的一阶与二阶模糊厌恶，指出二阶模糊厌恶下最优决策取决于主观信念，而一阶模糊厌恶下零模糊暴露可能是最优的，并用金融、保险和合同实例说明其经济意义。
Different models of uncertainty aversion imply strikingly different economic behavior. The key to understanding these differences lies in the dichotomy between first-order and second-order ambiguity aversion, which I define here. My definition and its characterization are independent of specific representations of decisions under uncertainty. I show that with second-order ambiguity aversion, a positive exposure to ambiguity is optimal if and only if there is a subjective belief such that the act’s expected outcome is positive. With first-order ambiguity aversion, zero exposure to ambiguity can be optimal. Examples in finance, insurance, and contracting demonstrate the economic relevance of this dichotomy. This paper was accepted by Han Bleichrodt, decision analysis.