Below are some of the projects that I am working on currently.


Vertical Migration Externalities with Mark Colas

Regional Science and Urban Economics, 2023

State income taxes affect federal income tax revenue by shifting the spatial distribution of households between high- and low-productivity states, thereby changing household incomes and tax payments. We derive an expression for these fiscal externalities of state taxes in terms of estimable statistics. An empirical quantification using American Community Survey data reveals that the externalities range from large and negative in some states, to large and positive in others. In California, an increase in the state income tax rate and the resulting change in the distribution of households across states lead to a decrease in federal income tax revenue of 39 cents for every dollar of California tax revenue raised. The externality amounts to a 0.27% decrease in total federal income tax revenue for a 1 pp increase in California’s state tax rate. Our results raise the possibility that state taxes may be set too high in high-productivity states, and set too low in low-productivity states.

Working Papers

Optimal Subsidies for Residential Solar with Mark Colas

We study the optimal design of spatially differentiated subsidies for residential solar panels. We build a structural model of solar panel demand and electricity production across the US and estimate the model by combining 1) remotely sensed data on residential solar panels, 2) power-plant-level data on hourly production and emissions, and 3) a state-of-the-art air pollution model. The current subsidies lead to severe spatial misallocation. National funding for subsidies under the current system exceeds the unconstrained optimum by seven-fold.

CESifo Working Paper 10446. This paper was previously titled, “Optimal Solar Subsidies”

**Left:** Optimal solar subsidies. **Right:** Installations as a percent of optimal.**Left:** Optimal solar subsidies. **Right:** Installations as a percent of optimal.

Left: Optimal solar subsidies. Right: Installations as a percent of optimal.

Works in Progress

Perinatal health effects of herbicides: Glyphosate, Roundup, and the rollout of GM crops with Ed Rubin

The advent of herbicide-tolerant genetically modified (GM) crops led to rapid and widespread use of the herbicide glyphosate throughout US agriculture. In the two decades following GM-seed introduction, the volume of glyphosate used in the US increased by more than 750%. Despite glyphosate’s breadth and scale, science and policy remain unresolved re- garding its effects on human health. To identify the causal effect of glyphosate exposure on perinatal health, we combine (1) county-level variation in glyphosate use driven by (2) the timing of the release of GM technology and (3) differential geographic suitability for GM crops. Our results suggest glyphosate significantly reduces average birth weight and gestational length. We find effects across the birth-weight distribution, but low-weight births experienced the largest reductions. While our estimates may provide lower bounds— they are net of health benefits from reduced exposure to other pesticides—they suggest that glyphosate exposure accounted for 27-45% of the birth-weight decline rural counties experienced in the past twenty years.

The Distributional Impacts of Climate Change across U.S. Local Labor Markets with John Morehouse

Climate change has affected households around the globe, but its impacts are not homogenous across space. We show that climate change has thus far disproportionately exposed disadvantaged demographic groups. However, household adaptation also impacts the welfare consequences of this unequal burden. We develop and estimate a new spatial equilibrium model of local labor markets, allowing households to adapt to climate change by choosing their city, energy consumption, and housing. We then simulate counterfactual climates and decompose the value of each adaptation mechanism. The lowest income decile has welfare effects an order of magnitude larger than the highest income decile. Additionally, Black households are worse off by \(1.5\%\) of income relative to white households due to climate change to-date, and we project that gap to grow by an additional \(5-7\%\) by the end of the century.

Means Tested Solar Subsidies with Mark Colas