I analyze energy-efficiency policy as a prescription of a minimum-efficiency standard for energyusing household goods like cars, building insulation, and home appliances. Such a policy has two effects. At the intensive margin, a household that invests will choose a more efficient device. At the...

Policy-makers have increasingly turned to ‘in-work transfers’ to boost incomes among poorer workers and strengthen work incentives. One attraction of these is that labour supply elasticities are typically greatest at the extensive margin. Because in-work transfers are normally subject to...