A carbon tax is a promising tool for discouraging the greenhouse gas emissions that cause climate change. In principle, a well-designed tax could reduce the risk of climate change, minimize the cost of emissions reductions, encourage innovation in low-carbon technologies, and raise new public revenue. But designing a real-world carbon tax poses significant challenges. We analyze those challenges from a public finance perspective, emphasizing three tax policy design issues: setting the tax rate, collecting the tax, and using the resulting revenue. The benefits of a carbon tax will depend on how policymakers address those issues.

This paper reports on recent research showing that the severe recession of 2007-2009 and the weak recovery have been due to poor economic policies and the failure to implement good policies during the past decade. Monetary policy, fiscal policy, and regulatory policy became more discretionary, more interventionist, and less predictable in comparison with the previous two decades of better economic performance. At best these policies led to growth spurts, but were followed by retrenchments, averaging to poor performance. The paper also considers alternative views-that the equilibrium interest rate declined during the decade and that the seriousness of financial crisis caused the slow recovery.

Organs for transplantation are a scarce resource. Paying to increase the supply of organs is illegal in much of the world. We review efforts to increase transplantation by increasing the supply of available organs from living and deceased donors. Progress has been made in increasing the availability of living donor kidneys through kidney exchange. Recent legislation in Israel aims at encouraging deceased donation by awarding priority for receiving organs to registered donors. We also explore the manner in which organ donation is solicited and present evidence to suggest that some recent movement towards 'mandated choice' may be counterproductive.

The influence of peers could play an important role in the take up of social programs. However, estimating peer effects has proven challenging given the problems of reflection, correlated unobservables, and endogenous group membership. We overcome these identification issues in the context of paid paternity leave in Norway using a regression discontinuity design. We find strong evidence for substantial peer effects of program participation in both workplace and family networks. Coworkers and brothers are 11 and 15 percentage points, respectively, more likely to take paternity leave if their peer was exogenously induced to take up leave. The most likely mechanism is information transmission about the costs and benefits of taking paternity leave, including increased knowledge of how an employer will react. The estimated peer effect snowballs over time, as the first peer interacts with a second peer, the second peer interacts with a third peer, and so on. This leads to long-run participation rates which are substantially higher than would otherwise be expected.

We show that, among college graduates, earnings differentials across field of study have increased substantially since the early 1990s. We study the degree to which this increase can be accounted for by changes in the labor market return to skills associated with a major. To do so, we define major-specific measures of the relative importance of abstract, routine, and manual tasks on the job, by linking majors to the occupations they typically lead to. Changes in the relationship between earnings and these measures can account for about two-thirds of the rise in inequality.

When regulated firms are offered compensation to prevent them from relocating, efficiency requires that payments be distributed across firms so as to equalize marginal relocation probabilities, weighted by the damage caused by relocation. We formalize this fundamental economic logic and apply it to analyzing compensation rules proposed under the EU Emissions Trading Scheme, where emission permits are allocated free of charge to carbon-intensive and trade-exposed industries. We show that this practice results in substantial overcompensation for given carbon leakage risk. Efficient permit allocation reduces the aggregate risk of job loss by more than half without increasing aggregate compensation.