Market failure, government inefficiency, and optimal R&D policy

This paper presents a growth model that can explain the coexistence of intellectual property rights and R&D subsidies as a response to the presence of both market and government failures. The framework can also generate the observed positive correlation between these two policy tools

Health cycles and health transitions

We study the dynamics of poverty and health in a model of endogenous growth and rational health behavior. Population health depends on the prevalence of infectious diseases that can be avoided through costly prevention. The incentive to do so comes from the negative effects of ill health on the quality and quantity of life. The model can generate a poverty trap where infectious diseases cycle between high and low prevalence. These cycles originate from the rationality of preventive behavior in contrast to the predator-prey dynamics of epidemiological models. We calibrate the model to reflect sub-Saharan Africa's recent economic recovery and analyze policy alternatives. Unconditional transfers are found to improve welfare relative to conditional health-based transfers: at low income levels, income growth (quality of life) is valued more than improvements to health (quantity of life)

Paths of Development in Open Economies: The Role of Land

This paper shows, within a Heckscher-Ohlin version of the two-sector neoclassical growth model, that land, besides having long-run effects, is also a main determinant of the speed of convergence toward the steady state when there are cross-sector capital share differences. This result stands in sharp contrast to the predictions of standard neoclassical growth frameworks, and calls for a reinterpretation of the conditional-convergence and the resource-curse findings. More specifically, the model predicts that the former finding requires the existence not only of diminishing returns but also of relatively small differences in capital shares across sectors. With respect to the latter finding, our results imply that it may be a consequence of purely transitional effects of natural riches on growth, and that it can not be interpreted as evidence that natural inputs necessarily harm long-run welfare. We produce empirical evidence on the relationship between land, income levels, and growth rates, and present data on cross-sector capital shares. We claim that most of that evidence is consistent with the predictions of the model.

Diseases and Development

This paper examines two related questions: what effects do infectious diseases exert on growth and development, and are they quantitatively important? We present evidence on the effect of health and infectious diseases on economic development using Hansen’s (2000) endogenous threshold methodology. Taking into account various proxies for infectious diseases as potential threshold variables we show that countries are clustered in regimes that obey different growth paths and thus provide direct evidence of threshold effects. Motivated by this evidence we propose an epidemiological overlapping generations model where the transmission and incidence of an infectious disease depend upon economic incentives and rational behavior. The economic cost of the disease comes from its effect on mortality (infected individuals can die prematurely) and morbidity (lower productivity and/or lower flow of utility from a given consumption bundle). Our main theoretical finding is that if infectious diseases are particularly virulent or debilitating, growth- or development-traps are possible. Numerical results from a calibrated version of the model show that threshold effects of diseases are quantitatively important and in particular, significant health interventions are required to propel disease-afflicted countries to a high-growth trajectory.

Convergence in a dynamic Heckscher–Ohlin model with land

Convergence among nations that share the same preferences and technologies is a key result of the closed-economy neoclassical growth framework that has received substantial support in the data. However, Heckscher–Ohlin versions of the two-sector neoclassical growth model predict that nations that differ in their capital–labor ratios may not converge to the same steady state, even if they are identical in all other aspects. This is a puzzling result that warns us about potential dangers of international trade. In this paper we show that when land, an input in fixed supply, is introduced into the model, international trade in goods no longer limits the capacity of poor nations to catch up with the advanced world

Neoclassical growth and the natural resource curse puzzle

We advance a novel mechanism that helps to explain the puzzling evidence on the natural resource curse. The new channel arises in a standard dynamic Heckscher-Ohlin model composed of small-open economies that take international output prices as given. Within this framework, a more capital-intensive primary sector implies that natural-resource abundant economies grow more slowly along the adjustment path. This effect might be only temporary because the natural input also affects long-run income, and not necessarily in the same direction as transitional growth. We produce quantitative results that show that the new mechanism can account for a significant fraction of the observed output growth gap between resource rich and resource poor U.S. states

The public and private marginal product of capital

Why doesn't capital flow to developing countries as predicted by the neoclassical model? What are the direction and degree of capital misallocation across nations? We revisit these questions by removing public capital from total capital to achieve a more accurate estimate of the marginal productivity of private capital. We calculate MPK schedules in a large sample of advanced and developing countries. Our main result is that, in terms of the Lucas paradox, private capital is allocated remarkably efficiently across nations. Tentative estimates of the marginal productivity of public capital suggest that the deadweight loss from public capital misallocation across countries can be much larger than the one from private capital