摘要：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 information transactions has a simple analytic characterization in terms of the relative entropy from priors to posteriors, and it also connects naturally with a recent index of riskiness
关键词：informativeness; information transactions; Kullback-Leibler di-;vergence; relative entropy; decision under uncertainty; investment; Blackwell;ordering.
