We examine the generalizability of internally valid estimates of causal effects in a fixed population over time when that population is subject to aggregate shocks. This temporal external validity is shown to depend upon the distribution of the aggregate shocks and the interaction between these...

Scholars differ on whether Federal Reserve intervention mitigated banking panics during the Great Depression and in recent years. The last panic prior to the Depression sheds light on this debate. In April 1929, a fruit fly infestation in Florida forced the U.S. government to quarantine fruit...

Corn prices increased sharply in the summer of 2012 due to expected production shortfalls in the United States, which produces roughly 40% of the world's corn. A heat wave in July adversely affected corn production. We extend earlier statistical models of county-level corn yields in the Eastern...

Most American financial crises of the postbellum gold-standard era were caused by fluctuations in the cotton harvest due to exogenous factors such as weather. The transmission channel ran through export revenues and financial markets under the pre-1914 monetary regime. A poor cotton harvest...

We investigate the link between agricultural productivity and net migration in the United States using a county-level panel for the most recent period of 1970-2009. In rural counties of the Corn Belt, we find a statistically significant relationship between changes in net outmigration and...

We present a new framework to identify demand and supply elasticities of agricultural commodities using yield shocks - deviations from a time trend of output per area, which are predominantly caused by weather fluctuations. Demand is identified using current-period shocks that give rise to...

We report results from a large randomized natural field experiment conducted in southwestern China in the context of insurance for sows. Our study sheds light on two important questions about microinsurance. First, how does access to formal insurance affect farmers' production decisions? Second,...

Concern about declining growth in crop yields has renewed debates about the ability of biotechnology to promote food security. While numerous experimental and farm-level studies have found that adoption of genetically engineered crops has been associated with yield gains, aggregate and...

Crop diseases and how they are managed can have a large impact on agricultural productivity. This paper discusses the effects on agricultural productivity of Verticillium dahliae, a soil borne fungus that is introduced to the soil via infested spinach seeds and that causes subsequent lettuce...