People often need to choose between alternatives with known probabilities (risk) and alternatives with unknown probabilities (ambiguity). Such decisions are characterized by attitudes towards ambiguity, which are distinct from risk attitudes. Most studies of ambiguity attitudes have focused on...

Bayesian updating is the dominant theory of learning. However, the theory is silent about how individuals react to events that were previously unforeseeable or unforeseen. Building on a recently developed axiomatic framework to analyze such situations, we test if subjects update their beliefs...

There is a large literature showing that willingness-to-accept (WTA) is usually much higher than willingness-to-pay (WTP) in empirical studies although they should be roughly equal according to traditional economic theory. A second stream of literature shows that people are typically ambiguity...

An extensive literature has studied ambiguity aversion in economic decision making, and how ambiguity aversion can account for empirically observed violations of expected utility-based theories. Almost all relevant applied models presume a general dislike of ambiguity. In this paper, we provide...