Random matching models with a continuum population are widely used in economics to study environments where agents interact in small coalitions. This paper provides foundations to such models. In particular, the paper establishes an existence result for random matchings that are universal in the sense that certain desirable properties are satisfied for any assignment of types to agents. The result applies to infinitely many types of agents, thus covering random matching models which are currently used in the literature without a foundation. Furthermore, the paper provides conditions guaranteeing uniqueness of random matching.
JEL classification: C00, C02, C73, C78Keywords: Random matching; Involution; Independence; Continuum population; Fubini extension * We thank an anonymous referee for valuable comments and for suggestions on how to improve the presentation of the material of this paper.