We determine optimal discretionary monetary policy in a New Keynesian model when nominal interest rates are bounded below by zero. Nominal interest rates should be lowered faster in response to adverse shocks than in the case without bound. Such ‘pre-emptive easing’ is optimal because...

This paper shows that absent a commitment technology, central banks can nevertheless achieve the (timeless-)optimal commitment equilibrium if they are delegated with an objective function that is different from the societal one. In a prototypical forward-looking New Keynesian model, I develop a...

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 Söderlind, 2004). In this paper we show that the structural-form...

This paper considers a general class of nonlinear rational-expectations models in which policymakers seek to maximize an objective function that may be household expected utility. We show how to derive a target criterion that is: (i) consistent with the model's structural equations, (ii) strong...

Inflation-targeting central banks have only imperfect knowledge about the effect of policy decisions on inflation. An important source of uncertainty is the relationship between inflation and unemployment. This Paper studies the optimal monetary policy in the presence of uncertainty about the...

Rational expectations are often used as a strong argument against policy activism, as they may undermine or neutralize the policymaker’s actions. Although this sometimes happens, rational expectations do not always imply policy invariance or ineffectiveness. In fact, in certain circumstances...

Should one think of zero nominal interest rates as an undesirable liquidity trap or as the desirable Friedman rule? I use three different frameworks to discuss this issue. First, I restate Cole and Kocherlakota's (1998) analysis of Friedman's rule: short run increases in the money stock -...

In this Paper we study the role of the exchange rate in conducting monetary policy in an economy with near-zero nominal interest rates as experienced in Japan since the mid-1990s. Our analysis is based on an estimated model of Japan, the United States and the euro area with rational expectations...

Since John Taylor's (1993) seminal paper, a large literature has argued that active interest rate feedback rules, that is, rules that respond to increases in inflation with a more than one-for-one increase in the nominal interest rate, are stabilizing. In this paper, we argue that once the zero...

This paper uses a DSGE model to examine the effects of an expansion in government spending in a liquidity trap. The spending multiplier can be much larger than in the normal situation if the liquidity trap is very prolonged, and the budgetary costs minimal. But given this "fiscal free lunch," it...