A principal's production decision imposes a negative externality on an agent. The principal may be a pollution-generating firm, the agent may be a nearby town. The principal offers a contract to the agent, who has the right to be free of pollution. Then the agent privately learns the disutility...

We compare heteroskedasticity-robust inference methods with a large-scale Monte Carlo study based on regressions from 155 reproduction packages of leading economic journals. The results confirm established wisdom and uncover new insights. Among well established methods HC2 standard errors with...