These notes are intended as a do-it-yourself course in economic growth along lines suggested by Lucas ("On the Mechanics of Economic Development"). We examine in turn the neoclassical growth model; theories of endogenous growth, including learning-by-doing, increasing returns to scale, and externalities; and dynamic comparative advantage in trade. Salient features of growing economies and microeconomic evidence on production processes are used to evaluate alternatives. Exercises supplement the text.

This paper presents a simple counterexample to the belief that policy cooperation among benevolent governments is desirable. It also explains circumstances under which such counterexamples are possible and relates them to the literature on time inconsistency.

This paper presents a simple counterexample to the belief that policy cooperation among benevolent governments is desirable. It also explains circumstances under which such counterexamples are possible and relates them to the literature on time inconsistency.

We show that in a dynamic Heckscher-Ohlin model the timing of a country’s development relative to the rest of the world affects the path of the country’s development. A country that begins the development process later than most of the rest of the world—a late-bloomer—ends up with a permanently lower level of income than the early-blooming countries that developed earlier. This is true even though the late-bloomer has the same preferences, technology, and initial capital stock that the early-bloomers had when they started the process of development. This result stands in stark contrast to that of the standard one-sector growth model in which identical countries converge to a unique steady state, regardless of when they start to develop.

In the modern theory of growth, monopoly plays a crucial role both as a cause and an effect of innovation. Innovative firms, it is argued, would have insufficient incentive to innovate should the prospect of monopoly power not be present. This theme of monopoly runs throughout the theory of growth, international trade, and industrial organization. We argue that monopoly is neither needed for, nor a necessary consequence of, innovation. In particular, intellectual property is not necessary for, and may hurt more than help, innovation and growth. We argue that, as a practical matter, it is more likely to hurt.

In models in which convergence in income levels across closed countries is driven by faster accumulation of a productive factor in the poorer countries, opening these countries to trade can stop convergence and even cause divergence. We make this point using a dynamic Heckscher-Ohlin model — a combination of a static two-good, two-factor Heckscher-Ohlin trade model and a two-sector growth model — with infinitely lived consumers where international borrowing and lending are not permitted. We obtain two main results: First, countries that differ only in their initial endowments of capital per worker may converge or diverge in income levels over time, depending on the elasticity of substitution between traded goods. Divergence can occur for parameter values that would imply convergence in a world of closed economies and vice versa. Second, factor price equalization in a given period does not imply factor price equalization in future periods.

We contrast the properties of dynamic Heckscher-Ohlin models with overlapping generations with those of models with infinitely lived consumers under both closed and open international capital markets. In both environments, if capital is mobile, factor price equalization occurs after the initial period. If capital is not mobile, the properties of equilibria differ drastically across environments: With infinitely lived consumers, factor prices equalize in any steady state or cycle and, in general, there is positive trade in any steady state or cycle. With overlapping generations, we construct examples with steady states and cycles in which factor prices are not equalized, and any equilibrium that converges to a steady state or a cycle with factor price equalization has no trade after a finite number of periods.

Applied general equilibrium (AGE) models, which feature multiple countries, multiple industries, and input-output linkages across industries, have been the dominant tool for evaluating the impact of trade reforms since the 1980s. We review how these models are used to perform policy analysis and document their shortcomings in predicting the industry-level effects of past trade reforms. We argue that, to improve their performance, AGE models need to incorporate product-level data on bilateral trade relations by industry and better model how trade reforms lower bilateral trade costs. We use the least traded products methodology of Kehoe et al. (2015) to provide guidance on how improvements can be made. We provide further suggestions on how AGE models can incorporate recent advances in quantitative trade theory to improve their predictive ability and better quantify the gains from trade liberalization.