Signaling games with infinite action spaces may have no sequential equilibrium. We prove that adding cheap talk to these games solves the non-existence problem; the sequential equilibrium outcome correspondence is upper hemi-continuous. In addition, when the signaling space has sufficiently many...

We prove that the English auction (with bidders that need not be ex ante identical and may have interdependent valuations) has an efficient ex post equilibrium. We establish this result for environments where it has not been previously obtained. We also prove two versions of the...

We examine market-clearing prices and allocations in economies where agents' demand functions are undominated relative to their beliefs about other agents' actions. For sufficiently large economies and give certain restrictions on beliefs, the resulting allocations are nearly competitive.

For a class of infinite signaling games, the perfect Bayesian equilibrium strategies of finite approximating games converge to equilibrium strategies of the infinite game. This proves the existence of perfect Bayesian equilibrium for that class of games. It is well known that in general,...

The No Surcharge Rule (NSR) prevents merchants from charging more to consumers who pay by card versus other means ("cash"). We consider a payment network facing local monopolist merchants that serve two consumer groups, card users and cash users. Unlike in prior work, transaction quantities are...