A REVELATION PRINCIPLE FOR COMPETING MECHANISMS

In modelling competition among mechanism designers, it is necessary to specify the set of feasible mechanisms. These specifications are often borrowed from the optimal mechanism design literature and exclude mechanisms that are natural in a competitive environment; for example, mechanisms that depend on the mechanisms chosen by competitors. This paper constructs a set of mechanisms that is universal in that any specific model of the feasible set can be embedded in it. An equilibrium for a specific model is robust if and only if it is an equilibrium also for the universal set of mechanisms. A key to the construction is a language for describing mechanisms that is not tied to any preconceived notions of the nature of competition.