Rationing and market: Structure and stability of equilibria

Abstract

In recent years, state control of the economy has increased in many countries. A number of states try to influence prices in key areas of economy, in particular by selling resources at fixed prices within given quotas. However, in real economies the governments cannot prevent economic agents from reselling rationed goods at the free market. The study of impact of rationing on the market prices is a difficult and challenging problem. In the present paper we consider an equilibrium model in which part of the goods within the limits of quotas is sold at fixed prices while the remaining goods are sold at market prices; the goods bought at fixed prices can also be resold at market prices. Economy depends on parameters, viz. total resources, incomes of the participants, quotas, and fixed prices. For special values of parameters, this model reduces to pure exchange and fixed income models and, in a sense, is a combination of these models. Basing on known properties of these special cases and using techniques of elementary differential topology, we study the existence of equilibria and their properties. Depending on the values of parameters, a (sufficiently general) economy may have a finite (even or odd) number of equilibria, and in an important special case when total resources are subject to rationing and the total cost of allocated quotas coincides with the total income of the participants the equilibria form a one-dimensional manifold. We consider a generalized tâtonnement process and study its convergence under certain assumptions. It is shown that in our setup convergence of tâtonnement to an equilibrium may involve endogenous inflation.