We consider a production economy with a finite number of heterogeneous, infinitely lived consumers. We show that, if the economy is smooth enough, equilibria are locally unique for almost all endowments. We do so by converting the infinite dimensional fixed point problem stated in terms of prices and commodities into a finite dimensional Negishi problem involving individual weights in a social value function. By adding a set of artificial fixed factors to utility and production functions, we can write the equilibrium conditions equating spending and income for each consumer entirely in terms of time zero factor endowments and derivatives of the social value function.

In 1950 Mexico entered an economic takeoff and grew rapidly for more than 30 years. Growth stopped during the crises of 1982–1995, despite major reforms, including liberalization of foreign trade and investment. Since then growth has been modest. We analyze the economic history of Mexico 1877–2010. We conclude that the growth 1950–1981 was driven by urbanization, industrialization, and education and that Mexico would have grown even more rapidly if trade and investment had been liberalized sooner. If Mexico is to resume rapid growth — so that it can approach U.S. levels of income — it needs further reforms.

To illustrate the use of social accounting matrices (SAMs) in applied general equilibrium (GE) modeling, we use an aggregated SAM for the Spanish economy to calibrate a simple applied GE model. The idea is to construct artificial people—households, government, and a foreign sector—who make the same transactions in the equilibrium of the model economy as do their counterparts in the data. This calibration procedure can be augmented, or partially substituted for, by statistical estimation of key parameters. We show the usefulness of such a model by presenting the results of a comparative exercise that mimics the policy changes that took place in Spain during its 1986 integration into the European Community. Sub-sequent data shows the model results to be remarkably accurate, especially if we account for other major shocks affected the Spanish economy in 1986.

The current tool of choice for analyzing the impact of a potential North American Free Trade Agreement on the economies of Canada, Mexico, and the United States is the static applied general equilibrium model. Although this type of model can do a good job in analyzing, and even in predicting, the impact of trade liberalization or tax reform on relative prices and resource allocation over a short time horizon, it does not attempt to capture the impact of government policy on growth rates. For this we need a dynamic model. This paper outlines some of the issues that confront a researcher interested in building a dynamic general equilibrium model to assess the potential economic impact of a NAFTA, including the impact on growth rates. Simple calculations based on preliminary empirical work indicate that the dynamic benefits of increased openness could dwarf the static benefits found by more conventional applied general equilibrium models.

In 1985–86 the authors were members of a team that constructed a static applied general equilibrium model that was used to analyze the impact on the Spanish economy of the 1986 fiscal reform, which accompanied Spain’s entry into the European Community. This paper compares the results obtained to recently published data for 1985–87; we find that the model performed well in predicting the changes in relative prices and resource allocation that actually occurred, particularly if we incorporate exogenous shocks that affected the Spanish economy in 1986. We also analyze the sensitivity of the results to alternative specifications of the labor market and macroeconomic closure rules; we find that the central results are robust.

Economic equilibria are usually solutions to fixed point problems rather than solutions to convex optimization problems. This leads to two difficulties that are closely related: First, equilibria may be difficult to compute. Second, a model economy may have more than one equilibrium. This paper explores these issues for a number of stylized economies, including static economies that involve both pure exchange and production, economies that have infinite numbers of goods because of time and uncertainty, and economies with distortionary taxes and externalities. There are numerous numerical examples that illustrate the theory and could serve as test problems for algorithms.

We develop a theory of general equilibrium with endogenous debt limits in the form of individual rationality constraints similar to those in the dynamic consistency literature. If an agent defaults on a contract, he can be excluded from future contingent claims markets trading and can have his assets seized. He cannot be excluded from spot markets trading, however, and he has some private endowments that cannot be seized. All information is publicly held and common knowledge, and there is a complete set of contingent claims markets. Since there is complete information, an agent cannot enter into a contract in which he would have an incentive to default in some state. In general there is only partial insurance: variations in consumption may be imperfectly correlated across agents; interest rates may be lower than they would be without constraints; and equilibria may be Pareto ranked.