Knowledge that Transforms

This research examines the climatic origins of the diffusion of Neolithic agriculture across countries and archaeological sites. The theory suggests that a foraging society's history of climatic shocks shaped the timing of its adoption of farming. Specifically, as long as climatic disturbances did not lead to a collapse of the underlying resource base, the rate at which hunter-gatherers were climatically propelled to experiment with their habitats determined the accumulation of tacit knowledge complementary to farming. Consistent with the proposed hypothesis, the empirical investigation demonstrates that, conditional on biogeographic endowments, climatic volatility has a hump-shaped effect on the timing of the adoption of agriculture.

A common assumption is that the rise of drug testing among U.S. employers must have had negative consequences for black employment. I use variation in the timing and nature of drug testing regulation to identify the impacts of testing on black hiring. I find that adoption of protesting legislation increases black employment in the testing sector by 7% to 30% and relative wages by 1.4% to 13.0%, with the largest shifts among low-skilled black men. The results are consistent with ex ante discrimination and suggest that drug testing may benefit African Americans by enabling nonusing blacks to prove their status to employers.

Some have suggested that housing policy, embodied by the Community Reinvestment Act (CRA) and affordable housing goals of the government-sponsored enterprises (GSEs), caused the subprime crisis. We examine if these programs led to worse mortgage outcomes using two approaches. The first examines whether more activity by CRA-covered lenders, or more loan sales to the GSEs, was associated with worse outcomes. The second uses regression discontinuity to determine if outcomes were worse at the geographic thresholds used by each program. Our results suggest that neither program played a significant role in the subprime crisis.

Previous studies have demonstrated that a multitude of options can lead to choice overload, reducing decision quality. Through controlled experiments, we examine sequential choice architectures that enable the choice set to remain large while potentially reducing the effect of choice overload. A specific tournament-style architecture achieves this goal. An alternate architecture in which subjects compare each subset of options to the most preferred option encountered thus far fails to improve performance due to the status quo bias. Subject preferences over different choice architectures are negatively correlated with performance, suggesting that providing choice over architectures might reduce the quality of decisions.

A leading explanation in the economic literature is that monetary policy has real effects on the economy because firms incur a cost when changing prices. Using a unique database of cost and retail price changes, we find that variation in menu costs results in up to 13.3% fewer price increases. We confirm that these effects are allocative and have a persistent impact on both prices and unit sales. We provide evidence that the menu cost channel operates only when cost increases are small in magnitude, which is consistent with theory and provides the first empirical evidence of boundary conditions.

Climate policy has favored costly measures that implicitly or explicitly subsidize lowcarbon fuels.We simulate four transportation sector policies: cap and trade (CAT), ethanol subsidies, a renewable fuel standard (RFS), and a lowcarbon fuel standard. Our simulations confirm that alternatives to CAT are 2.5 to 4 times more costly but are amenable to adoption due to right-skewed distributions of gains. We analyze voting on the Waxman-Markey (WM) CAT bill. Conditional on a district’s CAT gains, a district’s RFS gains are negatively correlated with the likelihood of voting for WM. Our analysis supports campaign contributions as a partial mechanism.

We employ a weighted repeat rent estimator to construct quarterly indexes that expand the profession’s ability to make cross-sectional comparisons of housing markets. Our analysis shows that there is considerable heterogeneity in the behavior of rents across cities over the 2000–2010 decade, but the number of cities and years for which nominal rents fell is substantial; rents fell in many cities following the onset of the housing crisis in 2007; and the repeat rent and Bureau of Labor Statistics indexes differ due to sampling and construction methods.

We evaluate the role skin color plays in earnings and employment for black males in the NLSY97. By applying a novel, scaled measure of skin tone to a nationally representative sample and by estimating the evolution of labor market differentials over time, we bridge a burgeoning literature on skin color with more established literatures on wage differentials and labor market discrimination. We find that while intraracial wage gaps widen with experience, gaps between the lightest-skinned black workers and whites remain constant, suggesting that a blurring of the color line elicits subtle yet meaningful variation in earnings differentials over time.

Based on two strands of theoretical research, this paper provides new evidence on how fares are jointly affected by in-flight seat availability and purchasing date. As capacity-based theories predict, it emerges that fares monotonically and substantially increase with flight occupancy. After controlling for capacity utilization, our analysis also supports time-based theories, indicating a U-shaped temporal profile over a two-month booking period, as well as a sharp increase in fares in the two weeks prior to departure.

Using detailed U.S. and Spanish export data, we document that trade costs of a per-shipment nature are associated with less frequent and larger shipments (i.e., more lumpiness) in international trade. This finding is pervasive across broad product categories, but most apparent for industrial supplies, parts and accessories, and food products.