This paper examines the application of quasi-experimental methods in environmental economics. We begin with two observations: i) standard quasi-experimental methods, first applied in other microeconomic fields, typically assume unit-level treatments that do not spill over across units; (ii)...

Between 1990 and 2008, emissions of the most common air pollutants from U.S. manufacturing fell by 60 percent, even as real U.S. manufacturing output grew substantially. This paper develops a quantitative model to explain how changes in trade, environmental regulation, productivity, and consumer...