What determines the relationship between pollution and growth? Are the forces that explain the behavior over time of these quantities potentially useful to understand more generally the relationship between policies and growth? In this paper, we make a first attempt to analyze the equilibrium behavior of two quantities—the level of pollution and the level of income—in a setting in which societies choose, via voting, how much to regulate pollution. Our major finding is that, consistent with the evidence, the relationship between pollution and growth need not be monotone and that the precise equilibrium nature of the relationship between the two variables depends on whether individuals vote over effluent charges or directly restrict the choice of technology. Moreover, our analysis of the pollution problem suggests that, more generally, endogenous policy choices should be taken seriously as potential sources of heterogeneity when studying cross country differences in economic performance.

We consider a real business cycle model with an externality in production. Depending on parameter values, the model has sunspot equilibria, cyclical and chaotic equilibria, and equilibria with deterministic or stochastic regime switching. We study the implications of this model environment for automatic stabilizer tax systems. Stabilization is desirable because the efficient allocations are characterized by constant employment and output growth. We identify an automatic stabilizer income tax-subsidy schedule that supports the efficient allocations as the unique equilibrium outcome. That schedule has two properties: (i) it specifies the tax rate to be an increasing function of aggregate employment, and (ii) earnings are subsidized when aggregate employment is at its efficient level. The first feature eliminates ine¢cient, fluctuating equilibria, while the second induces agents to internalize the externality.

This paper uses a tractable macroeconomic model with idiosyncratic human capital risk and incomplete markets to analyze the growth and welfare effects of business cycles. The analysis is based on the assumption that the elimination of business cycles eliminates the variation in idiosyncratic risk. The paper shows that a reduction in the variation in idiosyncratic risk decreases the ratio of physical to human capital and increases the total investment return and welfare. If the degree of risk aversion is less than or equal to one, then economic growth is enhanced. This paper also provides a quantitative assessment of the macroeconomic effects of business cycles based on a calibrated version of the model. Even for relatively small degrees of risk aversion (around one) the model implies that the elimination of business cycles has substantial effects on investment in physical and human capital, economic growth, and welfare. JEL Classification: D52, E32, O40

∗I thank Leonard Dudley, Bentley MacLeod, and seminar participants at Queens Uni-versity for useful comments. Financial support from the C.R.D.E. and from the FCAR is gratefully acknowledged. Forthcoming Journal of Economic Theory. 1

I examine a model with two sectors of production: consumption and investment. In the model, indeterminacy of equilibria results due to the presence of small sector-specific externalities in production. In fact, I find that indeterminacy results with a certain, minimum value of the externality in the investment sector, even with no externality in the consumption sector. I find that the indeterminacy properties of the model vary, depending on the form of the utility function. For example, with utility that is logarithmic in consumption, these properties are completely independent of the value of the externality in the consumption sector.

In this paper we present a recursive method for the computation of dynamic competitive equilibria in models with heterogeneous agents and market frictions. This method is based on a convergent operator over an expanded set of state variables. The fixed point of this operator defines the set of all Markovian equilibria. We study approximation properties of the operator as well as the convergence of the moments of simulated sample paths. We apply our numerical algorithm to two growth models, an overlapping generations economy with money, and an asset pricing model with financial frictions.

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The aim of the paper is to explore the link between agent’s heterogeneity and indeterminacy in a general equilibrium economy. The framework is provided by the two-sector growth model with technological externalities of Boldrin and Rustichini (1994) in which heterogeneous agents are introduced. We first show that the occurrence of indeterminacy depends on the distribution in labor endowments and in shares on initial capital among the agents as well as on preferences and technology. We find that the sign of the effect of heterogeneity on indeterminacy is not pinned down by the standard properties of preferences, a fact that might be surprising in view of some recent results (as in Herrendorf et al. (2000)). However, when risk aversion is a concave or a slightly convex function, then heterogeneity is a factor that opposes the external effects in generating indeterminacy.

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Summary. In the present paper a tractable two-sector growth model with technological externalities and many countries is considered. It is shown that the occurrence of indeterminacy, a typical side-product of externalities, may appear due to the enlargement of the markets for goods and factors. Various scenarios of progressive levels of integration are considered. In particular, it is found that the integration into a common market on which countries trade the produced good and the inputs may lead to indeterminacy even when the equilibrium under full autarchy is determinate. A similar result holds when integration only affects consumption and capital goods. However, such result doesn’t occur if the inverse of relative risk aversion is a linear or concave function. We conclude that in many usual situations, as the one with CES preferences, indeterminacy and the associated fragility of expectations and financial instability, is not likely to be increased by market integration.