Inside and Outside Money, with an Application to the Russian Virtual Economy

We analyze the endogenous appearance of money substitutes, their interaction with outside money, and resulting distortions in the price system of an economy with large monopolies and wide-spread informal networks. The economy consists of productive, individually optimizing agents and less productive colluding agents who issue universally acceptable money substitutes. We distinguish equilibria by types of exchange both between agents of one type and between those of different types and show that for small trading frictions, only three types of equilibria can be sustained. A novelty of the analysis is that the agents issuing money substitutes survive by their collusion.