Volker Wieland

Interest-rate smoothing and optimal monetary policy: a review of recent empirical evidence

Abstract The Federal Reserve and other central banks tend to change short-term interest rates in sequences of small steps in the same direction and reverse the direction of interest rate movements only infrequently. These characteristics, often referred to as interest-rate smoothing, have led to criticism that policy responds too little and too late to macroeconomic developments. This paper, however, argues that interest-rate smoothing may in fact be optimal. We present empirical results from several recent papers that offer three explanations of interest-rate smoothing: forward-looking behavior by market participants, measurement error associated with key macroeconomic variables, and uncertainty regarding relevant structural parameters.

The Performance of Forecast-Based Monetary Policy Rules Under Model Uncertainty

We investigate the performance of forecast-based monetary policy rules using five macroeconomic models that reflect a wide range of views on aggregate dynamics. We identify the key characteristics of rules that are robust to model uncertainty: such rules respond to the one- year-ahead inflation forecast and to the current output gap and incorporate a substantial degree of policy inertia. In contrast, rules with longer forecast horizons are less robust and are prone to generating indeterminacy. Finally, we identify a robust benchmark rule that performs very well in all five models over a wide range of policy preferences.

Price Stability and Monetary Policy Effectiveness when Nominal Interest Rates are Bounded at Zero

This paper employs stochastic simulations of a small structural rational expectations model to investigate the consequences of the zero bound on nominal interest rates. We find that if the economy is subject to stochastic shocks similar in magnitude to those experienced in the United States over the 1980s and 1990s, the consequences of the zero bound are negligible for target inflation rates as low as 2 percent. However, the effects of the constraint are non-linear with respect to the inflation target and produce a quantitatively significant deterioration of the performance of the economy with targets between 0 and 1 percent. The variability of output increases significantly and that of inflation also rises somewhat. Also, we show that the asymmetry of the policy ineffectiveness induced by the zero bound generates a non-vertical long-run Phillips curve. Average output falls increasingly short of potential with lower inflation targets.

Inflation Zone Targeting

We study optimal monetary policy design in a simple model that deviates from the linear-quadratic paradigm and provides a rationale for the practice of inflation zone targeting. We show that the presence of either zone-quadratic preferences or a zone-linear relationship between inflation and economic activity provides strong incentives to deviate from conventional linear policies. We calibrate the model based on parameters for the U.S. and the euro area and employ a numerical dynamic programming algorithm to derive the optimal policies. With this algorithm, we examine the role of uncertainty, model structure and relative preference towards economic stability in determining the width of the implied targeted inflation zone. JEL Classification: E31, E52, E58, E61

Monetary Policy, Parameter Uncertainty and Optimal Learning

Since central banks have limited information concerning the transmission channel of monetary policy, they are faced with the difficult task of simultaneously controlling the policy target and estimating the impact of policy actions. A tradeoff between estimation and control arises because policy actions influence estimation and provide information which may improve future performance. I analyze this tradeoff in a simple model with parameter uncertainty and conduct dynamics simulations of the policymakers decision problem in the presence of the type of uncertainties that arose in the wake of German reunification. A policy that separates learning from control may induce a persistent upward bias in money growth and inflation, just as observed after unification. In contrast, the optimal learning strategy which exploits the tradeoff between control and estimation significantly improves stabilization performance and reduces the likelihood of inflationary bias.

Keynesian government spending multipliers and spillovers in the euro area

The global financial crisis has lead to a renewed interest in discretionary fiscal stimulus. Advocates of discretionary measures emphasize that government spending can stimulate additional private spending --- the so-called Keynesian multiplier effect. Thus, we investigate whether the discretionary spending announced by Euro area governments for 2009 and 2010 is likely to boost euro area GDP by more than one for one. Because of modeling uncertainty, it is essential that such policy evaluations be robust to alternative modeling assumptions and different parameterizations. Therefore, we use five different empirical macroeconomic models with Keynesian features such as price and wage rigidities to evaluate the impact of fiscal stimulus. Four of them suggest that the planned increase in government spending will reduce private spending for consumption and investment purposes significantly. If announced government expenditures are implemented with delay the initial effect on euro area GDP, when stimulus is most needed, may even be negative. Traditional Keynesian multiplier effects only arise in a model that ignores the forward-looking behavioral response of consumers and firms. Using a multi-country model, we find that spillovers between euro area countries are negligible or even negative, because direct demand effects are offset by the indirect effect of euro appreciation.

The zero-interest-rate bound and the role of the exchange rate for monetary policy in Japan

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 and nominal rigidities. First, we provide a quantitative analysis of the impact of the zero bound on the effectiveness of interest rate policy in Japan in terms of stabilizing output and inflation. Then we evaluate three concrete proposals that focus on depreciation of the currency as a way to ameliorate the effect of the zero bound and evade a potential liquidity trap. Finally, we investigate the international consequences of these proposals.

A Quantitative Exploration of the Opportunistic Approach to Disinflation

Under a conventional policy rule, a central bank adjusts its policy rate linearly according to the gap between inflation and its target, and the gap between output and its potential. Under “the opportunistic approach to disinflation” a central bank controls inflation aggressively when inflation is far from its target, but concentrates more on output stabilization when inflation is close to its target, allowing supply shocks and unforeseen fluctuations in aggregate demand to move inflation within a certain band. We use stochastic simulations of a small-scale rational expectations model to contrast the behavior of output and inflation under opportunistic and linear rules.

Monetary Policy and Uncertainty about the Natural Unemployment Rate

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 natural unemployment rate, the short-run inflation-unemployment tradeoff and the degree of inflation persistence in a simple macroeconomic model, which incorporates rational learning by the central bank as well as private sector agents. Two conflicting motives drive the optimal policy. In the static version of the model, uncertainty provides a motive for the policymaker to move more cautiously than she would if she knew the true parameters. In the dynamic version, uncertainty also motivates an element of experimentation in policy. I find that the optimal policy that balances the cautionary and activist motives typically exhibits gradualism, that is, it still remains less aggressive than a policy that disregards parameter uncertainty. Exceptions occur when uncertainty is very high and in inflation close to target.

Learning and control in a changing economic environment

Abstract In this paper we investigate optimal Bayesian learning and control with lagged dependent variables and time-varying unknown parameters. We assess both the performance of alternative decision rules, as in the computationally-oriented dual control literature, as well as the dynamics of learning and convergence of beliefs, as in the more theoretically oriented Bayesian learning literature. Our numerical results indicate that the optimal decision rule involves a noticeable degree of experimentation for moderate to large levels of uncertainty. In most situations though, the optimal rule will remain less activist than a certainty-equivalent rule and induce gradualism. Exceptions occur when the process to be controlled is near the deterministic steady state. In this situation, we find that the decision-maker will repeatedly undertake costly experiments. The extent of optimal experimentation is lower if the unknown parameter is perceived to vary over time. In contrast to the fixed parameter case, however, parameter uncertainty is continually renewed and the incentive to experiment never ceases.