We study the information design problem in a single-unit auction setting. The information designer controls independent private signals according to which the buyers infer their binary private value. Assuming that the seller adopts Myerson (1981) optimal auction in response, we characterize both...

We investigate Groves mechanisms for economies where (i) a social outcome specifies a group of winning agents, and (ii) a cost function associates each group with a monetary cost. In particular, we characterize both (i) the class of cost functions for which there are Groves mechanisms such that...