Humans are notoriously bad at understanding probabilities, exhibiting a host of biases and distortions that are context dependent. This has serious consequences on how we assess risks and make decisions. Several theories have been developed to replace the normative rational expectation theory at...

Consider any investor who fears ruin facing any set of investments that satisfy noarbitrage. Before investing, he can purchase information about the state of nature in the form of an information structure. Given his prior, information structure α is more informative than information structure...

An information transaction entails the purchase of information. Formally, it consists of an information structure together with a price. We develop an index of the appeal of information transactions, which is derived as a dual to the agent’s preferences for information. The index of...

We examine risk taking when the bank's preferences exhibit smooth ambiguity aversion. Ambiguity is modeled by a second-order probability distribution that captures the bank's uncertainty about which of the subjective beliefs govern the financial asset return risk. Ambiguity preferences are...

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...

Knightian uncertainty leads naturally to nonlinear expectations. We introduce a corresponding equilibrium concept with sublinear prices and establish their existence. In general, such equilibria lead to Pareto inefficiency and coincide with Arrow-Debreu equilibria only if the values of net...

Delegation bears an intrinsic form of uncertainty. Investors hire managers for their superior models of asset markets, but delegation outcome is uncertain precisely because managers' model is unknown to investors. We model investors' delegation decision as a trade-off between asset return...

Decision makers often take risky decisions on the behalf of others rather than for themselves. Competing theoretical models predict both, higher as well as lower levels of risk aversion when taking risk for others, and the experimental evidence is mixed. In our within-subject design, money...

In this paper, we study an irreversible investment problem under Knightian uncertainty. In a general framework, in which Knightian uncertainty is modeled through a set of multiple priors, we prove existence and uniqueness of the optimal investment plan, and derive necessary and sufficient...

In real world financial markets, dividend processes as well as fundamental values are governed by imprecision; neither the objective probabilities of returns nor the actual amounts of possible returns are known for certain. With a novel experimental approach, we analyze the impact of risk,...