Model builders face ambiguity about the true data generating process. Consequently, they need to deal with ambiguity attitudes (inside uncertainty) and ambiguous financial reality (outside uncertainty) when developing and estimating financial models. We introduce a novel approach for...

We investigate what it means for one act to be more ambiguous than another. The question is evidently analogous to asking what makes one prospect riskier than another, but beliefs are neither objective nor representable by a unique probability. Our starting point is an abstract class of...

This paper studies the pricing implications of the sole ambiguity aversion, in a Lucas’ tree economy where asset returns are ambiguous. Abstracting from a specific functional form, we disentangle the model-specific effect from the effect of ambiguity aversion. In addition, we allow the...

Between August and September 2012, the American political magazine, Foreign Policy asked a total of 62 well-known US economists what they saw as the main reason for the slow recovery of the labor market. The most common response was "uncertainty" (31 percent). But what exactly does this term...