@techreport{NBERw10840,
 title = "Optimal Monetary and Fiscal Policy in a Liquidity Trap",
 author = "Gauti B. Eggertsson and Michael Woodford",
 institution = "National Bureau of Economic Research",
 type = "Working Paper",
 series = "Working Paper Series",
 number = "10840",
 year = "2004",
 month = "October",
 URL = "http://www.nber.org/papers/w10840",
 abstract = {In previous work (Eggertsson and Woodford, 2003), we characterized the optimal conduct of monetary policy when a real disturbance causes the natural rate of interest to be temporarily negative, so that the zero lower bound on nominal interest rates binds, and showed that commitment to a history-dependent policy rule can greatly increase welfare relative to the outcome under a purely forward-looking inflation target. Here we consider in addition optimal tax policy in response to such a disturbance, to determine the extent to which fiscal policy can help to mitigate the distortions resulting from the zero bound, and to consider whether a history-dependent monetary policy commitment continues to be important when fiscal policy is appropriately adjusted. We find that even in a model where complete tax smoothing would be optimal as long as the zero bound never binds, it is optimal to temporarily adjust tax rates in response to a binding zero bound; but when taxes have only a supply-side effect, the optimal policy requires that the tax rate be raised during the "trap", while committing to lower tax rates below their long-run level later. An optimal policy commitment is still history-dependent, in general, but the gains from departing from a strict inflation target are modest in the case that fiscal policy responds to the real disturbance in an appropriate way.},
}