Knowledge that Transforms

The empirical literature on economic growth and development has moved from the study of proximate determinants to the analysis of ever deeper, more fundamental factors, rooted in long-term history. A growing body of new empirical work focuses on the measurement and estimation of the effects of historical variables on contemporary income by explicitly taking into account the ancestral composition of current populations. The evidence suggests that economic development is affected by traits that have been transmitted across generations over the very long run. This article surveys this new literature and provides a framework to discuss different channels through which intergenerationally transmitted characteristics may impact economic development, biologically (via genetic or epigenetic transmission) and culturally (via behavioral or symbolic transmission). An important issue is whether historically transmitted traits have affected development through their direct impact on productivity, or have operated indirectly as barriers to the diffusion of productivity-enhancing innovations across populations.

Home bias is a perennial feature of international capital markets. We review various explanations of this puzzling phenomenon highlighting recent developments in macroeconomic modeling that incorporate international portfolio choices in standard two-country general equilibrium models. We refer to this new literature as Open Economy Financial Macroeconomics. We focus on three broad classes of explanations: (i) hedging motives in frictionless financial markets (real exchange rate and nontradable income risk), (ii) asset trade costs in international financial markets (such as transaction costs or differences in tax treatments between national and foreign assets), and (iii) informational frictions and behavioral biases. Recent theories call for new portfolio facts beyond equity home bias. We present new evidence on cross-border asset holdings across different types of assets: equities, bonds and bank lending and new micro data on institutional holdings of equity at the fund level. These data should inform macroeconomic modeling of the open economy and a growing literature of models of delegated investment.

Harstad and Selten's article in this forum performs a valuable service by highlighting the dominance of optimization-based models over boundedly rational models in modern microeconomics, and questioning whether optimization-based models are a better way forward than boundedly rational models. This article complements Rabin's response to Harstad and Selten, focusing on modeling strategic behavior. I consider Harstad and Selten's examples and proposed boundedly rational models in the light of modern behavioral economics and behavioral game theory, commenting on the challenges that remain and the most promising ways forward.

Transportation is a vital sector of the U.S. economy based on consumers', firms', and government's enormous expenditures in money and time and on its effect on virtually all other sectors in the economy. I assess the performance of the transportation system and consider how it could be improved by analyzing whether the United States has the optimal mix of public and private provision. The empirical evidence indicates that our hugely important transportation system has been compromised by various government policies and the significant welfare costs motivate either vastly improving public provision or expanding the role of the private sector.

Scientists describe the scale of the risks from unmanaged climate change as potentially immense. However, the scientific models, because they omit key factors that are hard to capture precisely, appear to substantially underestimate these risks. Many economic models add further gross underassessment of risk because the assumptions built into the economic modeling on growth, damages and risks, come close to assuming directly that the impacts and costs will be modest and close to excluding the possibility of catastrophic outcomes. A new generation of models is needed in all three of climate science, impact and economics with a still stronger focus on lives and livelihoods, including the risks of large-scale migration and conflicts.

Contingent charges for financial services, such as fees for unauthorized overdrafts, are often controversial. We study the economics of contingent charges in a stylized setting with naive and sophisticated consumers. We contrast situations where the naive benefit from the presence of sophisticated consumers with situations where competition works to subsidize the sophisticated at the expense of the naive, arguably unfairly. The case for regulatory intervention in these situations depends in good part, but not only, on the weight placed on distributional concerns. The economic and legal issues at stake are well illustrated by a case on bank charges recently decided by the U.K. Supreme Court.

The publication of Daniel Kahneman's book, Thinking, Fast and Slow, is a major intellectual event. The book summarizes, but also integrates, the research that Kahneman has done over the past forty years, beginning with his path-breaking work with the late Amos Tversky. The broad theme of this research is that human beings are intuitive thinkers and that human intuition is imperfect, with the result that judgments and choices often deviate substantially from the predictions of normative statistical and economic models. In this review, I discuss some broad ideas and themes of the book, describe some economic applications, and suggest future directions for research that the book points to, especially in decision theory.

In the United States, health care technology has contributed to rising survival rates, yet health care spending relative to GDP has also grown more rapidly than in any other country. We develop a model of patient demand and supplier behavior to explain these parallel trends in technology growth and cost growth. We show that health care productivity depends on the heterogeneity of treatment effects across patients, the shape of the health production function, and the cost structure of procedures such as MRIs with high fixed costs and low marginal costs. The model implies a typology of medical technology productivity: (I) highly cost-effective “home run” innovations with little chance of overuse, such as anti-retroviral therapy for HIV, (II) treatments highly effective for some but not for all (e.g., stents), and (III) “gray area” treatments with uncertain clinical value such as ICU days among chronically ill patients. Not surprisingly, countries adopting Category I and effective Category II treatments gain the greatest health improvements, while countries adopting ineffective Category II and Category III treatments experience the most rapid cost growth. Ultimately, economic and political resistance in the United States to ever-rising tax rates will likely slow cost growth, with uncertain effects on technology growth.

This paper reviews four decades of economics research on the brain drain, with a focus on recent contributions and on development issues. We first assess the magnitude, intensity, and determinants of the brain drain, showing that brain drain (or high-skill) migration is becoming a dominant pattern of international migration and a major aspect of globalization. We then use a stylized growth model to analyze the various channels through which a brain drain affects the sending countries and review the evidence on these channels. The recent empirical literature shows that high-skill emigration need not deplete a country's human capital stock and can generate positive network externalities. Three case studies are also considered: the African medical brain drain, the exodus of European scientists to the United States, and the role of the Indian diaspora in the development of India's information technology sector. We conclude with a discussion of the implications of the analysis for education, immigration, and international taxation policies in a global context.

This paper synthesizes the expanding corporate social responsibility (CSR) literature. We define CSR from an economic perspective and develop a CSR taxonomy that connects disparate approaches to the subject. We explore whether CSR should exist and investigate conditions when CSR may produce higher welfare than other public good provision channels. We also explore why CSR does exist. Here, we integrate theoretical predictions with empirical findings from economic and noneconomic sources. We find limited systematic empirical evidence in favor of CSR mechanisms related to induced innovation, moral hazard, shareholder preferences, or labor markets. In contrast, we uncover consistent empirical evidence in favor of CSR mechanisms related to consumer markets, private politics, and public politics.