Research Database

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.

In this paper we examine the evidence for two competing views of how monetary and financial disturbances influenced the real economy during the national banking era, 1880-1914. According to the monetarist view, monetary disturbances affected the real economy through changes on the liability side of the banking system's balance sheet independent of the composition of bank portfolios. According to the credit rationing view, equilibrium credit rationing in a world of asymmetric information can explain short-run fluctuations in real output. Using structural VARs we incorporate monetary variables in credit models and credit variables in monetarist models, with inconclusive results. To resolve this ambiguity, we invoke the institutional features of the national banking era. Most of the variation in bank loans is accounted for by loans secured by stock, which in turn reflect volatility in the stock market. When account is taken of the stock market, the influence of credit in the VAR model is greatly reduced, while the influence of money remains robust. The breakdown of the composition of bank loans into stock market loans (traded in open asset markets) and other business loans (a possible setting for credit rationing) reveals that other business loans remained remarkably stable over the business cycle.

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.

This paper proposes a model of diversifiable uncertainty, irreversible investment decisions, and endogenous growth. The detailed microeconomic structure of the model makes it possible to study the. general equilibrium effects of obstacles to labor mobility, due to institutional as well as technological features of the economy. Labor mobility costs reduce private returns to investment, and the resulting slower rate of endogenous growth unambiguously lowers a representative individual's welfare. Turnover costs can have positive effects on full employment equilibrium wages when all external effects are disregarded: this may help explain why policy and institutions often tend to decrease labor mobility in reality, rather than to enhance it. Lower flexibility, however, reduces the growth rate of wages in endogenous growth equilibrium, with negative welfare effects even for agents who own only labor.

In this paper we study the relationship between wealth, income distribution and growth in a game-theoretic context in which property rights are not completely enforcable. We consider equilibrium paths of accumulation which yield players utilities that are at least as high as those that they could obtain by appropriating higher consumption at the present and suffering retaliation later on. We focus on those subgame perfect equilibria which are constrained Pareto-efficient (second best). In this set of equilibria we study how the level of wealth affects growth. In particular we consider cases which produce classical traps (with standard concave technologies): growth may not be possible from low levels of wealth because of incentive constraints while policies (sometimes even first-best policies) that lead to growth are sustainable as equilibria from high levels of wealth. We also study cases which we classify as the "Mancur Olson" type: first best policies are used at low levels of wealth along these constrained Pareto efficient equilibria, but first best policies are not sustainable at higher levels of wealth where growth slows down. We also consider the unequal weighting of players to ace the subgame perfect equiliria on the constrained Pareto frontier. We explore the relation between sustainable growth rates and the level of inequality in the distribution of income.

This paper develops the Kiyotaki-Wright model of monetary general equilibrium in which trade is bilateral and enforced by requiring that transactions be quid pro quo, and studies which goods are chosen, and under what conditions, as media of exchange. We prove the existence of a rational expectations equilibrium in which agents' expectations concerning trading opportunities are realized in the present and all future periods. We also show that, exceptional cases aside, no rational expectations barter equilibrium exists; that an equilibrium generally supports multiple money goods; and that a fiat money (i.e., a good that is produced, has minimum storage costs, but is not consumed) cannot be traded in rational expectations equilibrium.

Results in Lucas (1987) suggest that if public policy can affect the growth rate of the economy, the welfare implications of alternative policies will be large. In this paper, a stochastic, dynamic general equilibrium model with endogenous growth and money is examined. In this setting, inflation lowers growth through its effect on the return to work. However, the welfare costs of higher inflation are extremely modest.