Model uncertainty has the potential to change importantly how monetary policy should be conducted, making it an issue that central banks cannot ignore. In this paper, I use a standard new Keynesian business cycle model to analyze the behavior of a central bank that conducts policy with...

To conduct policy efficiently, central banks must use available data to infer, or learn, the relevant structural relationships in the economy. However, because a central bank's policy affects economic outcomes, the chosen policy may help or hinder its efforts to learn. This paper examines...

We use robust control techniques to study the effects of model uncertainty on monetary policy in an estimated, semi-structural, small-open-economy model of the U.K. Compared to the closed economy, the presence of an exchange rate channel for monetary policy not only produces new trade-offs for...

The Calvo pricing model that lies at the heart of many New Keynesian business cycle models has been roundly criticized for being inconsistent both with time series data on inflation and with micro-data on the frequency of price changes. In this paper we show that a modified version of the Gali...

Robust control allows policymakers to formulate policies that guard against model misspecification. The principal tools used to solve robust control problems are state-space methods (see Hansen and Sargent, 2006, and Giordani and Soderlind, 2004). In this paper we show that the structural-form...

This paper studies robust control problems when policy is set with commitment. One contribution of the paper is to articulate an approximating equilibrium that differs importantly from that developed in Hansen and Sargent (2003). The paper illustrates how the proposed approximating equilibrium...

This paper considers the optimal degree of monetary-discretion when the central bank conducts policy based on its private information about the state of the economy and is unable to commit. Society seeks to maximize social welfare by imposing restrictions on the central bank's actions over time,...

Many central banks in developed countries have had very low policy rates for quite some time. A growing number are experimenting with official rates that are negative. We develop a New Keynesian model in which the zero lower bound (ZLB) on nominal interest rates is imposed as an occasionally...