Alex Cohen

Postdoctoral Associate, Yale University School of Management

Ph.D., Yale University Department of Economics

I am a postdoctoral associate at the Yale School of Management. I completed my Ph.D. in economics from Yale University in May 2015. As a researcher, I am interested in empirically examining the impact of policies, programs and products designed to promote public well-being across a range of settings. In my work, I use a variety of applied econometric tools, including randomized experiments, instrumental variables, differences-in-differences and dynamic panel estimation.

Working Papers

The Effectiveness of Overlapping Pollution Regulation: Evidence from the Ban on Phosphate in Dishwasher Detergent (with David Keiser) [June 2015] revise and resubmit at the Journal of Public Economics

Summary: In 2010, several U.S. states implemented bans on dishwasher detergents containing high levels of phosphates, which are known to cause costly environmental damage. Using multiple datasets from wastewater treatment facilities, we show that existing regulations at facilities diminished the impacts of this ban. As a result, the ban achieved only a fraction of its intended reductions in phosphorous in waterways and the impacts were lowest in the most polluted waterways, which were more likely to be subject to existing regulation.

Estimating Farm Production Parameters with Measurement Error in Land Area [September 2015] under review

Summary: Measurement error in farm size (land area) can bias estimates of key parameters. One example is the relationship between farm size and productivity, which is important for predicting the effects of land redistribution policies. I develop a novel instrumental variables strategy that enables me to assess and correct bias from error in two commonly used measures of land area: farmers' self-reported area and GPS-estimated area. Using data from Tanzania, I find that there is substantial error in both measures but that bias from measurement error in GPS estimates is particularly severe.

Constraints on Labor and Land and the Return to Microcredit and Microinsurance [November 2015] new draft coming soon

Summary: Across the world, policymakers have devoted substantial attention and resources to relaxing financial constraints on small firms and farms through microcredit and microinsurance. I develop a novel test for whether imperfections in labor and land markets, which are common among small firms and farms in developing countries, weaken the impact of relaxing financial constraints. Applying my test to data from two randomized experiments, I find that these imperfections substantially limit firms' and farms' ability to take advantage of microcredit and microinsurance and may also stifle the effect of other programs designed to spur small firm and farm growth and profits.

Mentions: World Bank Development Impact blog

Dormant Working Paper

Farm Production Function Estimation: Lessons from Firms and Implications for Measuring Misallocation [June 2014]