The wide cross-country disparity in rates of economic growth is the most puzzling feature of the development process. This paper describes a class of models in which this heterogeneity in growth experiences can be the result of cross-country differences in government policy. These differences can also create incentives for labor migration from slow-growing to fast-growing countries. In the models considered, growth is endogeneous despite the absence of increasing returns because there is a "core" of capital goods that can be produced without the direct or indirect contribution of factors that cannot be accumulated, such as land.

Recent estimates of the potential growth effects of tax reform vary wildly, ranging from zero to eight percentage points. Using an endogenous growth model, we assess which model features and parameter values are important for determining the quantitative impact of tax reform. We find that the critical parameters are factor shares, depreciation rates, the elasticity of intertemporal substitution, and the elasticity of labor supply. The elasticities of substitution in production, on the other hand, are relatively unimportant. The quantitative estimates in several recent papers are compared with each other and with some of the evidence from U.S. experience. We find that Robert Lucas's conclusion, that tax reform would have little or no effect on the U.S. growth rate, is theoretically robust and consistent with the evidence.

Why do the countries of the world display considerable disparity in long-term growth rates? This paper examines the hypothesis that the answer lies in differences in national public policies that affect the incentives that individuals have to accumulate capital in both its physical and human forms. Our analysis shows that these incentive effects can induce large differences in long-run growth rates. Since many of the key tax rates are difficult to measure, our procedure is an indirect one. We work within a calibrated, two-sector endogenous growth model, which has its origins in the microeconomic literature on human capital formation. We show that national taxation can substantially affect long-run growth rates. In particular, for small open economies with substantial capital mobility, national taxation can readily lead to "development traps" (in which countries stagnate or regress) or to "growth miracles" (in which countries shift from little growth to rapid expansion). This influence of taxation on the rate of economic growth has important welfare implications: in basic endogenous growth models, the welfare cost of a 10 percent increase in the rate of income tax can be 40 times larger than in the basic neoclassical model.

Neoclassical transitional dynamics are a central element of standard macroeconomic theory. Quantitative experiments with the fixed-savings-rate models of the 1960's showed lengthy transitions, thus potentially rationalizing sustained differences in growth rates across countries. We investigate quantitative transitional dynamics in various neoclassical models with intertemporally optimizing households. Lengthy transitions occur only with very low intertemporal substitution. Generally, when one tries to explain sustained economic growth with transitional dynamics, there are extremely counterfactual implications. These result from the fact that implied marginal products are extraordinarily high in the early stages of development.

This paper investigates the sensitivity of Solow residual based measures of technology shocks to labor hoarding behavior. Using a structural model of labor hoarding and the identifying restriction that innovations to technology shocks are orthogonal to innovations in government consumption, we estimate the fraction of the variability of the Solow residual that is due to technology shocks. Our results support the view that a significant proportion of movements in the Solow residual are artifacts of labor hoarding behavior. Specifically, we estimate that the variance of innovations to technology is roughly 50 percent less than that implied by standard real business cycle models. In addition, our results suggest that existing real business cycle studies substantially overstate the extent to which technology shocks account for the variability of postwar aggregate U.S. output.

The wide cross-country disparity in rates of economic growth is the most puzzling feature of the development process. This paper describes a class of models in which this heterogeneity in growth experiences can be the result of cross-country differences in government policy. These differences can also create incentives for labor migration from slow-growing to fast-growing countries. In the models considered, growth is endogenous, despite the absence of increasing returns, because there is a "core" of capital goods that can be produced without the direct or indirect contribution of factors that cannot be accumulated, such as land. Copyright 1991 by University of Chicago Press.

[We study the properties of the carry trade, a currency speculation strategy in which an investor borrows low-interest-rate currencies and lends high-interest-rate currencies. This strategy generates payoffs that are on average large and uncorrelated with traditional risk factors. We argue that these payoffs reflect a peso problem. The underlying peso event features high values of the stochastic discount factor rather than very large negative payoffs.]

The influential Krugman-Flood-Garber (KFG) model of balance of payment crises assumes that a fixed exchange rate is abandoned if and only if international reserves reach a critical threshold value. From a positive standpoint, the KFG rule is at odds with many episodes in which the central bank has plenty of international reserves at the time of abandonment. We study the optimal exit policy and show that from a normative standpoint, the KFG rule is generally suboptimal. We consider a model in which the fixed exchange rate regime has become unsustainable due to an unexpected increase in government spending. We show that when there are no exit costs, it is optimal to abandon immediately. When there are exit costs, the optimal abandonment time is a decreasing function of the size of the fiscal shock. For large fiscal shocks, immediate abandonment is optimal. Our model is consistent with evidence suggesting that many countries exit fixed exchange rate regimes with still plenty of international reserves in the central bank's vault.

Aggregate and sectoral comovement are central features of business cycles, so the ability to generate comovement is a natural litmus test for macroeconomic models. But it is a test that most models fail. We propose a unified model that generates aggregate and sectoral comovement in response to contemporaneous and news shocks about fundamentals. The fundamentals that we consider are aggregate and sectoral total factor productivity shocks as well as investment-specific technical change. The model has three key elements: variable capital utilization, adjustment costs to investment, and preferences that allow us to parameterize the strength of short-run wealth effects on the labor supply. (JEL E13, E20, E32)

We propose a model consistent with two observations. First, the tax rates adopted by different countries are generally uncorrelated with their growth performance. Second, countries that drastically reduce private incentives to invest severely hurt their growth performance. In our model, the effects of taxation on growth are highly nonlinear. Low tax rates have a very small impact on long-run growth rates. But as tax rates rise, their negative impact on growth rises dramatically. The median voter chooses tax rates that have a small impact on growth prospects, making the relation between tax rates and economic growth difficult to measure empirically.