Knowledge that Transforms

This study considers the eradication of hookworm disease from the American South as a test of the quantity-quality (Q-Q) framework of fertility. Eradication was principally a shock to the price of quality because of three factors: hookworm (i) depresses the return to human-capital investment, (ii) had a very low case-fatality rate, and (iii) had negligible prevalence among adults. Consistent with the Q-Q model, we find a significant decline in fertility associated with eradication. Relative sizes of fertility and human-capital responses to hookworm indicate that the Q-Q mechanism is of a similar magnitude to secular co-movements in these same variables.

This paper examines impacts of childhood health on socioeconomic status (SES) outcomes observed during adulthood: levels and trajectories of education, family income, household wealth, individual earnings, and labor supply. The analysis is conducted using panel data that collect these SES measures using a sample who were originally children and are now well into their adult years. Since all siblings are in the panel, unmeasured family and neighborhood background effects can be controlled for. With the exception of education, poor childhood health has a quantitatively large effect on all of these outcomes. Moreover, these estimated effects are larger when unobserved family effects are controlled.

We document that countries with higher initial education levels experienced faster value-added and employment growth in schooling-intensive industries in the 1980s and 1990s. This effect is robust to controls for other determinants of international specialization and becomes stronger when we focus on economies open to international trade. Our finding is consistent with schooling fostering the adoption of new technologies if such technologies are skilled-labor augmenting, as was the case in the 1980s and the 1990s. In line with international specialization theory, we also find that countries where education levels increased rapidly experienced stronger shifts in production toward schooling-intensive industries.

This paper analyzes welfare-state determinants of individual attitudes toward immigrants—within and across countries—and their interaction with labor market drivers of preferences. We consider two mechanisms through which a redistributive welfare system might adjust as a result of immigration. Under the first model, immigration has a larger impact on high-income individuals, while under the second one low-income individuals are those most affected. Individual attitudes are consistent with the first welfare-state model and with labor market determinants. In countries where immigration is unskilled, income is negatively correlated with pro-immigration preferences, while skill is positively correlated with them. These relationships are reversed in economies characterized by skilled migration.

How does firm entry affect innovation incentives in incumbent firms? Microdata suggest that there is heterogeneity across industries. Specifically, incumbent productivity growth and patenting is positively correlated with lagged greenfield foreign firm entry in technologically advanced industries, but not in laggard industries. In this paper we provide evidence that these correlations arise from a causal effect predicted by Schumpeterian growth theory—the threat of technologically advanced entry spurs innovation incentives in sectors close to the technology frontier, where successful innovation allows incumbents to survive the threat, but discourages innovation in laggard sectors, where the threat reduces incumbents' expected rents from innovating. We find that the empirical patterns hold using rich micro panel data for the United Kingdom. We control for the endogeneity of entry by exploiting major European and U.K. policy reforms, and allow for endogeneity of additional factors. We complement the analysis for foreign entry with evidence for domestic entry and entry through imports.

With climate change as prototype example, this paper analyzes the implications of structural uncertainty for the economics of low-probability, high-impact catastrophes. Even when updated by Bayesian learning, uncertain structural parameters induce a critical “tail fattening” of posterior-predictive distributions. Such fattened tails have strong implications for situations, like climate change, where a catastrophe is theoretically possible because prior knowledge cannot place sufficiently narrow bounds on overall damages. This paper shows that the economic consequences of fat-tailed structural uncertainty (along with unsureness about high-temperature damages) can readily outweigh the effects of discounting in climate-change policy analysis.