The data show large and persistent deviations of real exchange rates from purchasing power parity. Recent work has shown that to a large extent these movements are driven by deviations from the law of one price for traded goods. In the data, real and nominal exchange rates are about 6 times as...

The purpose of this paper is to construct a quantitative equilibrium model with price setting and use it to ask whether staggered price setting can generate persistent output fluctuations following monetary shocks. We construct a business cycle version of a standard sticky price model in which...

We document regularities in the distribution of relative incomes and patterns of investment in countries and over time. We develop a quantitative version of the neoclassical growth model with a broad measure of capital in which investment decisions are affected by distortions. These distortions...

The central finding of the recent structural vector autoregression (SVAR) literature with a differenced specification of hours is that technology shocks lead to a fall in hours. Researchers have used this finding to argue that real business cycle models are unpromising. We subject this SVAR...

We provide an introduction to optimal fiscal and monetary policy using the primal approach to optimal taxation. We use this approach to address how fiscal and monetary policy should be set over the long run and over the business cycle. We find four substantive lessons for policymaking: Capital...

This paper develops the quantitative implications of optimal fiscal policy in a business cycle model. In a stationary equilibrium the ex ante tax rate on capital income is approximately zero. There is an equivalence class of ex post capital income tax rates and bond policies that support a given...

We find conditions for the Friedman rule to be optimal in three standard models of money. These conditions are homotheticity and separability assumptions on preferences similar to those in the public finance literature on optimal uniform commodity taxation. We show that there is no connection...

Robert Solow has criticized our 2006 Journal of Economic Perspectives essay describing "Modern Macroeconomics in Practice." Solow eloquently voices the commonly heard complaint that too much macroeconomic work today starts with a model with a single type of agent. We argue that modern...

The optimal choice of a monetary policy instrument depends on how tight and transparent the available instruments are and on whether policymakers can commit to future policies. Tightness is always desirable; transparency is only if policymakers cannot commit. Interest rates, which can be made...

Financial crises are widely argued to be due to herd behavior. Yet recently developed models of herd behavior have been subjected to two critiques which seem to make them inapplicable to financial crises. Herds disappear from these models if two of their unappealing assumptions are modified: if...