We develop a revealed preference test for optimal acquisition of costly information. The test encompasses models of rational inattention, sequential signal processing, and search. We provide limits on the extent to which attention costs can be recovered from choice data. We experimentally elicit...

With complete information, choice of one option over another conveys preference. Yet when search is incomplete, this is not necessarily the case. It may instead reflect unawareness that a superior alternative was available. To separate these phenomena, we consider non-standard data on the...

We introduce a simple method of recovering attention costs from choice data. Our method rests on a precise analogy with production theory. Costs of attention determine consumer demand and consumer welfare just as a competitive firm's technology determines its supply curve and profits. We...