Accounting for loss of variety and factor reallocations in the welfare cost of regulations

This paper develops a multi-sector general equilibrium model with heterogeneous firms to account for both the direct cost of regulations on regulated firms as well as the indirect cost associated with loss of variety and factor reallocations. The model derives an analytical marginal abatement cost function, dividing the cost according to these direct and indirect effects, and explores the implications for optimal environmental policy. The model is numerically simulated using parameters for the U.S. manufacturing sector for criteria air pollutants, demonstrating that the direct cost of regulations understates the true cost. Moreover, because marginal abatement costs vary across industries, reallocating pollution across industries to achieve cost-effectiveness can generate modest cost savings.