One literature documents a significant, black-white gap in average test scores, while another finds a substantial narrowing of the gap during the 1980's, and stagnation in convergence after. We use two data sources -- the Long Term Trends NAEP and AFQT scores for the universe of applicants to...

Chay, Guryan and Mazumder (2009) found substantial racial convergence in AFQT and NAEP scores across cohorts born in the 1960's and early 1970's that was concentrated among blacks in the South. We demonstrated a close tracking between variation in the test score convergence across states and...

We use the Islamic holy month of Ramadan as a natural experiment in fasting and fetal health. In Michigan births 1989-2006, we find prenatal exposure to Ramadan among Arab mothers results in lower birthweight and reduced gestation length. Exposure to Ramadan in the first month of gestation is...

We consider the effects of daytime fasting by pregnant women during the lunar month of Ramadan on their children's test scores at age seven. Using English register data, we find that scores are .05 to .08 standard deviations lower for Pakistani and Bangladeshi students exposed to Ramadan in...

We estimate the impact of weather variation on agricultural output in Indonesia by examining the impact of local rainfall shocks on rice output at the district level. Our analysis makes use of local meteorological data on rainfall in combination with government administrative data on...

In a model of evolution driven by conflict between societies more powerful states have an advantage. When the influence of outsiders is small we show that this results in a tendency to hegemony. In a simple example in which institutions differ in their "exclusiveness" we find that these...

Typical models of bankruptcy and collateral rely on incomplete asset markets. In fact, bankruptcy and collateral add contingencies to asset markets. In some models, these contingencies can be used by consumers to achieve the same equilibrium allocations as in models with complete markets. In...

When considering the incentive of a monopolist to adopt an innovation, the textbook model assumes that it can instantaneously and seamlessly introduce the new technology. In fact, firms often face major problems in integrating new technologies. In some cases, firms have to (temporarily) produce...

A model of security design based on the principle of information aggregation and alignment is used to show that (i) firms needing to finance their operations should issue different securities to different groups of investors in order to aggregate their disparate information and (ii) each...

Intellectual property (IP) protection involves a trade-off between the undesirability of monopoly and the desirable encouragement of creation and innovation. Optimal policy depends on the quantitative strength of these two forces. We give a quantitative assessment of current IP policies. We...