Choice Group

A variety of findings in psychology and economics support the idea that some types of evidence are more "ambiguous" than others. Although widely discussed, there is no generally-accepted model of ambiguous evidence. I propose a new one: evidence is ambiguous iff it warrants higher-order uncertainty, i.e. warrants being uncertain about how uncertain it warrants being. I'll argue that this theory is formally tenable and philosophically attractive. Then I'll put it to empirical work: understanding ambiguity in terms of higher-order uncertainty helps to explain a variety of empirical effects, including biased processing of evidence, overconfidence and conservatism, and ambiguity aversion.