For political and practical reasons, environmental regulations sometimes treat point source polluters, such as power plants, differently from mobile source polluters, such as vehicles. This paper measures the extent of this regulatory asymmetry in the case of nitrogen oxides (NOx), the criteria...

Renewable fuel standards, low carbon fuel standards, and ethanol subsidies are popular policies to incentivize ethanol production and reduce emissions from transportation. Compared to carbon trading, these policies lead to large shifts in agricultural activity and unexpected social costs. We...