Trading Uncertainty and Market Form

This paper examines purely random multilateral matching among a large number of informationally isolated individuals who desire to trade. The structure of links among traders is characterized by means of random graphs, defined by a parameter that is chosen by prospective traders. Trading groups of all sizes (including pairs as a special case) result, but the size distribution may contain a mass point at infinity. That is, within a certain subset of the entire economy, trading uncertainty is entirely eliminated. The equilibrium price distribution consists of a mass point and of a mixture of densities.