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...

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...

In this paper we review some well-known simple models for portfolio selection under Knightian uncertainty, also known as ambiguity, and we compute a number of explicit optimal portfolio rules using elementary mathematical tools. In the case of a single period financial market, new results arise...