Optimal policy rules--including those regarding income taxation, commodity taxation, public goods, and externalities--are typically derived in models with homogeneous preferences. This article reconsiders many central results for the case in which preferences for commodities, public goods, and...

Many analysts have argued that energy efficiency investments offer an enormous "win-win" opportunity to both reduce negative externalities and save money. This overview paper presents a simple model of investment in energy-using capital stock with two types of market failures: first,...

This essay revisits the question of instrument choice for the regulation of externalities in the context of climate change. The central point is that the Pigouvian prescription to equate marginal control costs with the expected marginal benefits of damage reduction should guide the design of...

A substantial literature examines second-best environmental policy, focusing particularly on how the Pigouvian directive that marginal taxes should equal marginal external harms needs to be modified in light of the preexisting distortion due to labor income taxation. Additional literature is...

Is monetary policy less effective at increasing real output during periods of high volatility than during normal times? In this paper, I argue that greater volatility leads to an increase in aggregate price flexibility so that nominal stimulus mostly generates inflation rather than output...

This paper proposes a structural approach to measuring the effects of electoral accountability. We estimate a political agency model with imperfect information in order to identify and quantify discipline and selection effects, using data on U.S. governors for 1982-2012. We find that the...

What are the welfare effects of the information contained in macroeconomic statistics, central-bank communications, or news in the media? We address this question in a business-cycle framework that nests the neoclassical core of modern DSGE models. Earlier lessons that were based on "beauty...

This paper presents a model of information and political regime change. If enough citizens act against a regime, it is overthrown. Citizens are imperfectly informed about how hard this will be and the regime can, at a cost, engage in propaganda so that at face-value it seems hard. This...

Global games of regime change -- that is, coordination games of incomplete information in which a status quo is abandoned once a sufficiently large fraction of agents attacks it -- have been used to study crises phenomena such as currency attacks, bank runs, debt crises, and political change. We...

We consider a bilateral trading problem in which one or both parties makes relationship-specific investments before trade. Without adequate contractual protection, the prospect of later holdups discourages investment. We postulate that the parties can sign noncontingent contracts prior to...