A critical roadblock to modelling inventories of finished goods has been the claim that production and inventory decisions of a perfectly competitive firm are determined independently of each other. A basic goal of this study is to specify fundamental preferences of economic agents, technologies, constraints and market structures that are, in a rough way, capable of generating patterns of serial correlation and cross correlation between inventories and employment of factors of production that are consistent with those observed in the data. The claim is made that the time series for inventories, output and employment can be interpreted as emerging from a well specified dynamic, stochastic competitive equilibrium in which economic agents are assumed to form rational expectations about variables not included in their information sets. Inventories and employment will not be related in a direct way if and only if the price elasticity of demand for output is equal to infinity.
A new approach to market behavior is suggested. This approach has a coherent game theoretic foundaton, addresses such anomalous economic behaviors as strikes, rigid wages and unemployment, regulation of financial markets, depresssion, and nonmarket allocation, and, more generally, provides insights for Finance, Oligopoly Theory, Industrial Organization, and Macroeconomics. The central theme of the approach is that exchange technologies are a basic building block in a model, as are tastes, endowments, and production technologies. Moreover, the key feature of an institution of exchange is that it allows the making of a binding final offer.
General competitive analysis is extended to cover a dynamic, pure-exchange economy with privately observed shocks to preferences. In the linear, infinite-dimensional space containing lotteries we establish the existence of optima, the existence of competitive equilibria, and that every competitive equilibrium is an optimum. An example illustrates that rationing and securities with contrived risk have an equilibrium interpretation.
We use a model of pure, intertemporal exchange with spatially and information-ally separated markets to explain the existence of private securities which circulate and, hence, play a prominent role in exchange. The model, which utilizes a perfect foresight equilibrium concept, implies that a Schelling-type coordination problem can arise. It can happen that the amounts of circulating securities that are required to support an equilibrium and that are issued at the same time in informationally separated markets must satisfy restrictions not implied by individual maximization and market clearing in each market separately.
We study an overlapping generations model which contains a capital good that resembles actual gold. This capital good can he stored without physically depreciating and can, by using other resources, be converted back and forth between gold jewelry which yields utility directly and raw gold which does not.Under the assumption that the three utility-yielding objects—first and second period consumption and jewelry—are gross substitutes, stationary equilibria are shown to exist and are characterized; for some parameter values, there are inefficient equilibria, while for others there are efficient equilibria. Both types can be interpreted as commodity money equilibria.
Cover note : "An earlier version of this paper was presented at a seminar at MIT."
A necessary feature for equilibrium is that beliefs about the behavior of other agents are rational. We argue that in stationary OLG environments this implies that any future generation in the same situation as the initial generation must do as well as the initial generation did in that situation. We conclude that the existing equilibrium concepts in the literature do not satisfy this condition. We then propose an alternative equilibrium concept, organizational equilibrium, that satisfies this condition. We show that equilibrium exists, it is unique, and it improves over autarky without achieving optimality. Moreover, the equilibrium can be readily found by solving a maximization program.
Our goal is to provide a theoretical framework in which both positive and normative aspects of international currency can be addressed in a systematic way. To this end, we use the framework of random matching games and develop a two country model of the world economy, in which two national fiat currencies compete and may be circulated as media of exchange. There are multiple equilibria, which differ in the areas of circulation of the two currencies. In one equilibrium, the two national currencies are circulated only locally. In another, one of the national currencies is circulated as an international currency. There is also an equilibrium in which both currencies are accepted internationally. We also find an equilibrium in which the two currencies are directly exchanged. The existence conditions of these equilibria are characterized, using the relative country size and the degree of economic integration as the key parameters. In order to generate sharper predictions in the presence of multiple equilibria, we discuss an evolutionary approach to equilibrium selection, which is used to explain the evolution of the international currency as the two economies become more integrated. Some welfare implications are also discussed. For example, a country can improve its national welfare by letting its own currency circulated internationally, provided the domestic circulation is controlled for. When the total supply is fixed, however, a resulting currency shortage may reduce the national welfare.
We extend the analysis of Kiyotaki and Wright, who study an economy in which the different commodities that serve as media of exchange are determined endogenously. Kiyotaki and Wright consider only symmetric, steady-state, pure-strategy equilibria, and find that for some parameter values no such equilibria exist. We consider mixed-strategy equilibria and dynamic equilibria. We prove that a steady-state equilibrium exists for all parameter values and that the number of steady-state equilibria is generically finite. We also show, however, that there may be a continuum of dynamic equilibria. Further, some dynamic equilibria display cycles.
This paper surveys implementation theory when players have incomplete or asymmetric information, especially in economic environments. After the basic problem is introduced, the theory of implementation is summarized. Some coalitional considerations for implementation problems are discussed. For economies with asymmetric information, cooperative games based on incentive compatibility constraints or Bayesian incentive compatible mechanisms are derived and examined.
This paper surveys cooperative game theory when players have incomplete or asymmetric information, especially when the TU and NTU games are derived from economic models. First some results relating balanced games and markets are summarized, including theorems guaranteeing that the core is nonempty. Then the basic pure exchange economy is extended to include asymmetric information. The possibilities for such models to generate cooperative games are examined. Here the core is emphasized as a solution, and criteria are given for its nonemptiness. Finally, an alternative approach is explored based on Harsanyi’s formulation of games with incomplete information.
This paper investigates the characteristics of stationary single-price equilibrium in a monetary random-matching model where agents can hold an arbitrary amount of divisible money and where production is costly. At such an equilibrium, agents’ money holdings are endogenously determined and uniformly bounded. A refinement of weakly undominated strategies is argued to be necessary. It is shown that a continuum of single-price equilibria indexed by the aggregate real-money balance exists if one such equilibrium exists. Equilibria with different money-holdings upper bounds, hence different distributions, but with identical aggregate real-money balances, can coexist.