American Economic Review 104 (10), October 2014, 3154-3185 | With Swanson
According to standard macroeconomic models, the zero lower bound greatly reduces the effectiveness of monetary policy and increases the
efficacy of fiscal policy. However, private-sector decisions depend on the entire path of expected future short-term interest rates, not just the current short-term rate. Put differently, longer-term yields matter. We show how to measure the zero bound’s effects on yields of any maturity. Indeed, 1- and 2-year Treasury yields were surprisingly unconstrained throughout 2008 to 2010, suggesting that monetary and fiscal policy were about as effective as usual during this period. Only beginning in late 2011 did these yields become more constrained.
Journal of International Economics 92 (S1), 2014, 2-21 | With Swanson
The zero lower bound on nominal interest rates began to constrain many central banks’ setting of short-term interest rates in late 2008 or early 2009. According to standard macroeconomic models, this should have greatly reduced the effectiveness of monetary policy and increased the efficacy of fiscal policy. However, these models also imply that asset prices and private-sector decisions depend on the entire path of expected future short-term interest rates, not just the current level of the monetary policy rate. Thus, interest rates with a year or more to maturity are arguably more relevant for asset prices and the economy, and it is unclear to what extent those yields have been affected by the zero lower bound. In this paper, we apply the methods of Swanson and Williams (2013) to medium- and longer-term yields and exchange rates in the U.K. and Germany. In particular, we compare the sensitivity of these rates to macroeconomic news during periods when short-term interest rates were very low to that during normal times. We find that: 1) USD/GBP and USD/EUR exchange rates have been essentially unaffected by the zero lower bound, 2) yields
on German bunds were essentially unconstrained by the zero bound until late 2012, and 3) yields on U.K. gilts were substantially constrained by the zero lower bound in 2009 and 2012, but were surprisingly responsive to news in 2010–11. We compare these findings to the U.S. and discuss their broader implications.
Journal of Macroeconomics 38, 2013, 137-150
This paper examines the implications of uncertainty about the effects of monetary policy for optimal monetary policy with an application to the current situation. Using a stylized macroeconomic model, I derive optimal policies under uncertainty for both conventional and unconventional monetary policies. According to an estimated version of this model, the U.S. economy is currently suffering from a large and persistent adverse demand shock. Optimal monetary policy absent uncertainty would quickly restore real GDP close to its potential level and allow the inflation rate to rise temporarily above the longer-run target. By contrast, the optimal policy under uncertainty is more muted in its response. As a result, output and inflation return to target levels only gradually. This analysis highlights three important insights for monetary policy under uncertainty. First, even in the presence of considerable uncertainty about the effects of monetary policy, the optimal policy nevertheless responds strongly to shocks: uncertainty does not imply inaction. Second, one cannot simply look at point forecasts and judge whether policy is optimal. Indeed, once one recognizes uncertainty, some moderation in monetary policy may well be optimal. Third, in the context of multiple policy instruments, the optimal strategy is to rely on the instrument associated with the least uncertainty and use alternative, more uncertain instruments only when the least uncertain instrument is employed to its fullest extent possible.
In The Great Inflation: The Rebirth of Modern Central Banking, ed. by Michael D. Bordo and Athanasios Orphanides | The University of Chicago Press, 2013. 255-297 | With Orphanides
What monetary policy framework, if adopted by the Federal Reserve, would have avoided the Great Inflation of the 1960s and 1970s? We use counterfactual simulations of an estimated model of the U.S. economy to evaluate alternative monetary policy strategies. We show that policies constructed using modern optimal control techniques aimed at stabilizing inflation, economic activity, and interest rates would have succeeded in achieving a high degree of economic stability as well as price stability only if the Federal Reserve had possessed excellent information regarding the structure of the economy or if it had acted as if it placed relatively low weight on stabilizing the real economy. Neither condition held true. We document that policymakers at the time both had an overly optimistic view of the natural rate of unemployment and put a high priority on achieving full employment. We show that in the presence of realistic informational imperfections and with an emphasis on stabilizing economic activity, an optimal control approach would have failed to keep inflation expectations well anchored, resulting in high and highly volatile inflation during the 1970s. Finally, we show that a strategy of following a robust first-difference policy rule would have been highly effective at stabilizing inflation and unemployment in the presence of informational imperfections. This robust monetary policy rule yields simulated outcomes that are close to those seen during the period of the Great Moderation starting in the mid-1980s.
Journal of Money, Credit and Banking 44, 2012, 47-82 | With Chung, Laforte, and Reifschneider
Before the recent recession, the consensus among researchers was that the zero lower bound (ZLB) probably would not pose a significant problem for monetary policy as long as a central bank aimed for an inflation rate of about 2 percent; some have even argued that an appreciably lower target inflation rate would pose no problems. This paper reexamines this consensus in the wake of the financial crisis, which has seen policy rates at their effective lower bound for more than two years in the United States and Japan and near zero in many other countries. We conduct our analysis using a set of structural and time series statistical models. We find that the decline in economic activity and interest rates in the United States has generally been well outside forecast confidence bands of many empirical macroeconomic models. In contrast, the decline in inflation has been less surprising. We identify a number of factors that help to account for the degree to which models were surprised by recent events. First, uncertainty about model parameters and latent variables, which were typically ignored in past research, significantly increases the probability of hitting the ZLB. Second, models that are based primarily on the Great Moderation period severely understate the incidence and severity of ZLB events. Third, the propagation mechanisms and shocks embedded in standard DSGE models appear to be insufficient to generate sustained periods of policy being stuck at the ZLB, such as we now observe. We conclude that past estimates of the incidence and effects of the ZLB were too low and suggest a need for a general reexamination of the empirical adequacy of standard models. In addition to this statistical analysis, we show that the ZLB probably had a first-order impact on macroeconomic outcomes in the United States. Finally, we analyze the use of asset purchases as an alternative monetary policy tool when short-term interest rates are constrained by the ZLB, and find that the Federal Reserve’s asset purchases have been effective at mitigating the economic costs of the ZLB. In particular, model simulations indicate that the past and projected expansion of the Federal Reserve’s securities holdings since late 2008 will lower the unemployment rate, relative to what it would have been absent the purchases, by 1-1/2 percentage points by 2012. In addition, we find that the asset purchases have probably prevented the U.S. economy from falling into deflation.
In Handbook of Monetary Economics, 3B, ed. by Benjamin Friedman and Michael Woodford | North-Holland, 2011. 829-860
This paper focuses on simple normative rules for monetary policy which central banks can use to
guide their interest rate decisions. Such rules were first derived from research on empirical
monetary models with rational expectations and sticky prices built in the 1970s and 1980s.
During the past two decades substantial progress has been made in establishing that such rules
are robust. They perform well with a variety of newer and more rigorous models and policy
evaluation methods. Simple rules are also frequently more robust than fully optimal rules.
Important progress has also been made in understanding how to adjust simple rules to deal with
measurement error and expectations. Moreover, historical experience has shown that simple
rules can work well in the real world in that macroeconomic performance has been better when
central bank decisions were described by such rules. The recent financial crisis has not changed
these conclusions, but it has stimulated important research on how policy rules should deal with
asset bubbles and the zero bound on interest rates. Going forward the crisis has drawn attention
to the importance of research on international monetary issues and on the implications of
discretionary deviations from policy rules.
Journal of Applied Econometrics 25, January 2010, 129-143 | With Edge and Laubach
This paper examines welfare-maximizing monetary policy in an estimated micro-founded general equilibrium model of the U.S. economy where the policymaker faces uncertainty about model parameters. Uncertainty about parameters describing preferences and technology implies uncertainty about the model’s dynamics, utility-based welfare criterion, and the “natural” rates of output and interest that would prevail absent nominal rigidities. We estimate the degree of uncertainty regarding natural rates due to parameter uncertainty. We find that optimal Taylor rules under parameter uncertainty respond less to the output gap and more to price inflation than would be optimal absent parameter uncertainty. We also show that policy rules that focus solely on stabilizing wages and prices yield welfare outcomes very close to the first-best.
Imperfect Knowledge and the Pitfalls of Optimal Control Monetary Policy
In Central Banking, Analysis and Economic Policies: Monetary Policy Under Uncertainty and Learning, 13, ed. by Klaus Schmidt-Hebbel and Carl Walsh | Central Bank of Chile, 2009. 115-144 | With Orphanides
This paper examines the robustness characteristics of optimal control policies derived under the assumption of rational expectations to alternative models of expectations formation
and uncertainty about the natural rates of interest and unemployment. We assume that agents have imperfect knowledge about the precise structure of the economy and form expectations using a forecasting model that they continuously update based on incoming data. We also allow for central bank uncertainty regarding the natural rates of interest and unemployment. We find that the optimal control policy derived under the assumption of perfect knowledge about the structure of the economy can perform poorly when knowledge is imperfect. These problems are exacerbated by natural rate uncertainty, even when the central bank’s estimates of natural rates are efficient. We show that the optimal control approach can be made more robust to the presence of imperfect knowledge by deemphasizing the stabilization of real economic activity and interest rates relative to inflation in the central bank loss function. That is, robustness to the presence of imperfect knowledge about the economy provides an incentive to employ a “conservative” central banker. We then examine two types of simple monetary policy rules from the literature that have been
found to be robust to model misspecification in other contexts. We find that these policies are robust to the alternative models of learning that we study and natural rate uncertainty and outperform the optimal control policy and generally perform as well as the robust
optimal control policy that places less weight on stabilizing economic activity and interest rates.
Forecasting Recessions: The Puzzle of the Enduring Power of the Yield Curve
Journal of Business and Economic Statistics 27(4), 2009, 492-503 | With Rudebusch
We show that professional forecasters have essentially no ability to predict future recessions a few quarters ahead. This is particularly puzzling because, for at least the past two decades, researchers have provided much evidence that the yield curve, specifically the spread between long- and short-term interest rates, does contain useful information at that forecast horizon for predicting aggregate economic activity and, especially, for signalling future recessions. We document this puzzle and suggest that forecasters have generally placed too little weight on yield curve information when projecting declines in the aggregate economy.
Heeding Daedalus: Optimal Inflation and the Zero Lower Bound
Brookings Papers on Economic Activity 2009(2), Fall 2009, 1-37
This paper reexamines the implications of the zero lower bound on interest rates for monetary policy and the optimal choice of steady-state inflation in light of the experience of the recent global recession. There are two main findings. First, the zero lower bound did not materially contribute to the sharp declines in output in the United States and many other economies through the end of 2008,
but it is a significant factor slowing recovery. Model simulations imply that an additional 4 percentage points of rate cuts would have kept the unemployment rate from rising as much as it has and
would bring the unemployment and inflation rates more quickly
to steady-state values, but the zero bound precludes these actions. This inability to lower interest rates comes at
the cost of $1.8 trillion of foregone output over four years.
Second, if recent events are a harbinger of a significantly more adverse macroeconomic climate than experienced over the preceding two decades, then a 2 percent steady-state inflation rate may provide an inadequate buffer to keep the zero bound from having noticeable deleterious effects on the macroeconomy assuming the central bank follows the standard Taylor Rule. In such an adverse environment, stronger systematic countercyclical fiscal policy and/or alternative monetary policy strategies can mitigate the harmful effects of the zero bound with a 2 percent inflation target. However, even with such policies, an inflation target of 1 percent or lower could entail significant costs in terms of macroeconomic volatility.
American Economic Journal: Macroeconomics 1(1), January 2009, 58-83 | With Taylor
The recent financial crisis saw a dramatic and persistent jump in interest rate spreads between overnight federal funds and longer-term interbank loans. The Fed took several actions to reduce these spreads, including the creation of the Term Auction Facility (TAF). The effectiveness of these policies depends on the cause of the increased spreads such as counterparty risk, liquidity, or other factors. Using a no-arbitrage pricing framework and various measures of risk, we find robust evidence that increased counterparty risk contributed to the rise in spreads but do not find robust evidence that the TAF had a significant effect on spreads.
Journal of Monetary Economics 55, September 2008, S80-S96 | With Orphanides
The optimal control approach to monetary policy has garnered increased attention in recent years. Optimal control policies, however, are designed for the specific features of a particular model and therefore may not be robust to model misspecification. One important source of potential misspecification is how agents form expectations. Specifically, whether they know the complete structure of the model as assumed in rational expectations or learn using a forecasting model that they update based on incoming data. Simulations of an estimated model of the U.S. economy show that the optimal control policy derived under the assumption of rational expectations can perform poorly when agents learn. The optimal control approach can be made more robust to learning by deemphasizing the stabilization of real economic activity and interest rates relative to inflation in the central bank loss function. That is, robustness to learning provides an incentive to employ a “conservative” central banker. In contrast to optimal control policies, two types of simple monetary policy rules from the literature that have been found to be robust to model misspecification in other contexts are shown to be robust to learning.
In Asset Prices and Monetary Policy, ed. by J.Y. Campbell | Chicago: University of Chicago Press, 2008. 247-284 | With Rudebusch | Posted with the permission of the University Chicago Press.
The modern view of monetary policy stresses its role in shaping the entire yield curve of interest rates in order to achieve various macroeconomic objectives. A crucial element of this process involves guiding financial market expectations of future central bank actions. Recently, a few central banks have started to explicitly signal their future policy intentions to the public, and two of these banks have even begun publishing their internal interest rate projections. We examine the macroeconomic effects of direct revelation of a central bank’s expectations about the future path of the policy rate. We show that, in an economy where private agents have imperfect information about the determination of monetary policy, central bank communication of interest rate projections can help shape financial market expectations and may improve macroeconomic performance.
Learning and Shifts in Long-Run Productivity Growth
Journal of Monetary Economics 54(8), November 2007, 2421-2438 | With Edge and Laubach
An extensive literature has analyzed the macroeconomic effects of shocks to the level of aggregate productivity; however, there has been little corresponding research on sustained shifts in the growth rate of productivity. In this paper, we examine the effects of shocks to productivity growth in a dynamic general equilibrium model where agents do not directly observe whether shocks are transitory or persistent. We show that an estimated Kalman filter model using real-time data describes economists’ long-run productivity growth forecasts in the United States extremely well and that filtering has profound implications for the macroeconomic effects
of shifts in productivity growth.
Robust Monetary Policy with Imperfect Knowledge
Journal of Monetary Economics 54, August 2007, 1406-1435 | With Orphanides
We examine the performance and robustness properties of monetary policy rules in an estimated macroeconomic model in which the economy undergoes structural change and where private agents and the central bank possess imperfect knowledge about the true structure of the economy. Policymakers follow an interest rate rule aiming to maintain
price stability and to minimize fluctuations of unemployment around its natural rate but are uncertain about the economy’s natural rates of interest and unemployment and how private agents form expectations. In particular, we consider two models of expectations formation: rational expectations and learning. We show that in this environment the ability to stabilize the real side of the economy is significantly reduced relative to an economy under rational expectations with perfect knowledge. Furthermore, policies that would be optimal under perfect knowledge can perform very poorly if knowledge is imperfect. Efficient policies that take account of private learning and misperceptions of natural rates call for greater policy inertia, a more aggressive response to inflation, and a smaller response to the perceived unemployment gap than would be optimal if everyone had perfect knowledge of the economy. We show that such policies are quite robust to potential misspecification of private sector learning and the magnitude of variation in natural rates.
Inflation Targeting under Imperfect Knowledge
In Monetary Policy under Inflation Targeting, 11, ed. by Frederic Mishkin, Klaus Schmidt-Hebbel | Santiago, Chile: Central Bank of Chile, 2007. 77-123 | With Orphanides
A central tenet of inflation targeting is that establishing and maintaining well-anchored inflation expectations are essential. In this paper, we reexamine the role of key elements of the inflation targeting framework towards this end, in the context of an economy where economic agents have an imperfect understanding of the macroeconomic landscape within which the public forms expectations and policymakers must formulate and implement monetary policy. Using an estimated model of the U.S. economy, we show that monetary policy rules that would perform well under the assumption of rational expectations can perform very poorly when we introduce imperfect knowledge. We then examine the performance of an easily implemented policy rule that incorporates three key characteristics of inflation targeting: transparency, commitment to maintaining price stability, and close monitoring of inflation expectations, and find that all three play an important role in assuring its success. Our analysis suggests that simple difference rules in the spirit of Knut Wicksell excel at tethering inflation expectations to the central bank’s goal and in so doing achieve superior stabilization of inflation and economic activity in an environment of imperfect knowledge.
Monetary Policy under Uncertainty in Micro-Founded Macroeconomic Models
In NBER Macroeconomics Annual 2005, ed. by Gertler and Rogoff | Cambridge, MA: MIT Press, 2006. 229-287 | With Levin, Onatski, and N. Williams
We use a micro-founded macroeconometric modeling framework to investigate the design of monetary policy when the central bank faces uncertainty about the true structure of the economy. We apply Bayesian methods to estimate the parameters of the baseline specification using postwar U.S. data and then determine the policy under commitment that maximizes household welfare. We find that the performance of the optimal policy is closely matched by a simple operational rule that focuses solely on stabilizing nominal wage inflation. Furthermore, this simple wage stabilization rule is remarkably robust to uncertainty about the model
parameters and to various assumptions regarding the nature and incidence of the innovations. However, the characteristics of optimal policy are very sensitive to the specification of the wage contracting mechanism, thereby highlighting the importance of additional research regarding the structure of labor markets and wage determination.
Monetary Policy with Imperfect Knowledge
Journal of the European Economic Association 4(2-3), April 2006 | With Orphanides
We examine the performance and robustness of monetary policy rules when the central bank and the public have imperfect knowledge of the economy and continuously update their estimates of model parameters. We find that versions of the Taylor rule calibrated to perform well under rational expectations with perfect knowledge perform very poorly when agents are learning and the central bank faces uncertainty regarding natural rates. In contrast, difference rules, in which the change in the interest rate is determined by the inflation rate and the change in the unemployment rate, perform well when knowledge is both perfect and imperfect.
In Monetary Policy in an Environment of Low Inflation; Proceedings of the Bank of Korea International Conference 2006 | Seoul: Bank of Korea, 2006. 199-228
In theory, monetary policies that target the price level, as opposed to the inflation rate, should be highly effective at stabilizing the economy and avoiding deflation in the presence of the zero lower bound on nominal interest rates. With such a policy, if the short-term interest rate is constrained at zero and the inflation rate declines below its trend, the public expects that policy will eventually engineer a period of above-trend inflation that restores the price level to its target level. Expectations of future monetary accommodation stimulate output and inflation today, mitigating the effects of the zero bound. The effectiveness of such a policy strategy depends crucially on the alignment of the public’s and the central bank’s expectations of future policy actions. In this paper, we consider an environment where private agents have imperfect knowledge of the economy and therefore continuously reestimate the forecasting model that they use to form expectations. We find that imperfect knowledge on the part of the public, especially regarding monetary policy, can undermine the effectiveness of price-level-targeting strategies that would work well if the public had complete knowledge. For low inflation targets, the zero lower bound can cause a dramatic deterioration in macroeconomic performance with severe recessions occurring with alarming frequency. However, effective communication of the policy strategy that reduces the public’s confusion about the future course of monetary policy significantly reduces the stabilization costs associated with the zero bound. Finally, the combination of learning and the zero bound implies the need for a stronger policy response to movements in the price level than would otherwise be optimal and such a rule is effective at stabilizing both inflation and output in the presence of learning and the zero bound even with a low inflation target.
The Decline of Activist Monetary Policy: Natural Rate Misperceptions, Learning, and Expectations
Journal of Economic Dynamics and Control 29(11), November 2005, 1927-1950 | With Orphanides
We develop an estimated model of the U.S. economy in which agents form expectations by continually updating their beliefs regarding the behavior of the economy and monetary policy. We explore the effects of policymakers’ misperceptions of the natural rate of unemployment during the late 1960s and 1970s on the formation of expectations and macroeconomic outcomes. We find that the combination of monetary policy directed at tight stabilization of unemployment near its perceived natural rate and large real-time errors in estimates of the natural rate uprooted heretofore quiescent inflation expectations and contributed to poor macroeconomic performance. Had monetary policy reacted less aggressively to perceived unemployment gaps, inflation expectations would have remained anchored and the stagflation of the 1970s would have been avoided. Indeed, we find that less activist policies would have been more effective at stabilizing both inflation and unemployment. We argue that policymakers, learning from the experience of the 1970s, eschewed activist policies in favor of policies that concentrated on the achievement of price stability, contributing to the subsequent improvements in macroeconomic performance of the U.S. economy.
Using a Long-Term Interest Rate as the Monetary Policy Instrument
Journal of Monetary Economics 52(5), July 2005, 855-879 | With Rudebusch and McGough
Using a short-term interest rate as the monetary policy instrument can be
problematic near its zero-bound constraint. An alternative strategy is to use a long-term
interest rate as the policy instrument. We find when Taylor-type policy rules are used to
set the long rate in a standard New Keynesian model, indeterminacy–that is, multiple
rational expectations equilibria–may often result. However, a policy rule with a long rate
policy instrument that responds in a “forward-looking” fashion to inflation expectations
can avoid the problem of indeterminacy.
Review of Economic Dynamics 8(2), April 2005, 498-527 | With Orphanides
Central bankers frequently emphasize the critical importance of anchoring private inflation expectations for successful monetary policy and macroeconomic stabilization. In most monetary policy models, however, expectations are already anchored through the assumption of rational expectations and perfect knowledge of the economy. In this paper, we reexamine the role of inflation expectations by relaxing the assumption of rational expectations with perfect knowledge and positing, instead, that agents have imperfect knowledge of the precise structure of the economy and policymakers’ preferences, and rely on a perpetual learning technology to form expectations. We find that with learning, disturbances can give rise to endogenous inflation scares, that is, significant and persistent deviations of inflation expectations from those implied by rational expectations, even at long horizons. The presence of learning increases the sensitivity of inflation expectations and the term structure of interest rates to economic shocks, in line with the empirical evidence. We also explore the role of private
inflation expectations for the conduct of efficient monetary policy.
Under rational expectations, inflation expectations equal a linear combination
of macroeconomic variables and as such provide no additional information
to the policymaker. In contrast, under learning, private inflation
expectations follow a time-varying process and provide useful information
for the conduct of monetary policy.
Review of Economic Dynamics 8(1), January 2005, 1-27 | With Gilchrist
We embed the microeconomic decisions associated with investment under uncertainty, capacity utilization, and machine replacement in a general equilibrium model based on putty-clay technology. In the presence of irreversible factor proportions, a mean-preserving spread in the productivity of investment reduces investment at the project level, but raises aggregate investment, productivity, and output. Increases in uncertainty have important dynamic implications, causing sustained increases in investment and hours and a medium-term expansion in the growth rate of labor productivity.
Robust Estimation and Monetary Policy with Unobserved Structural Change
In Models and Monetary Policy: Research in the Tradition of Dale Henderson, Richard Porter, and Peter Tinsley, ed. by J. Faust, A. Orphanides, and D. Reifschneider | Washington, DC: Federal Reserve Board of Governors, 2005
This paper considers the joint problem of model estimation and implementation of monetary policy in the face of uncertainty regarding the process of structural change in the economy. I model unobserved structural change through time variation in the natural rates of interest and unemployment. I show that certainty equivalent optimal policies perform poorly when there is model uncertainty about the natural rate processes. I then examine the properties of combined estimation methods and policy rules that are robust to this type of model uncertainty. I find that weighted averages of sample means perform well as estimators of natural rates. The optimal policy under uncertainty responds more aggressively to inflation and less so to the perceived unemployment gap than the certainty equivalent policy. This robust estimation/policy combination is highly effective at mitigating the effects of natural rate mismeasurement.
Imperfect Knowledge, Inflation Expectations, and Monetary Policy
In Inflation Targeting, ed. by Bernanke and Woodford | Chicago: University of Chicago Press, 2004. 201-234 | With Orphanides
This paper investigates the role that imperfect knowledge about the structure of the economy plays in the formation of expectations, macroeconomic dynamics, and the efficient formulation of monetary policy. Economic agents rely on an adaptive learning technology to form expectations and to update continuously their beliefs regarding the dynamic structure of the economy based on incoming data. The process of perpetual learning introduces an additional layer of dynamic interaction between monetary policy and economic outcomes. We find that policies that would be efficient under rational expectations can perform poorly when knowledge is imperfect. In particular, policies that fail to maintain tight control over inflation are prone to episodes in which the public’s expectations of inflation become uncoupled from the policy objective and stagflation results, in a pattern similar to that experienced in the United States during the 1970s. Our results highlight the value of effective communication of a central bank’s inflation objective and of continued vigilance against inflation in anchoring inflation expectations and fostering macroeconomic stability.
Review of Economics and Statistics 85(4), 2003, 1063-1070 | With Laubach
The natural rate of interest–the real interest rate consistent with output equaling its natural rate and stable inflation–plays a central role in macroeconomic theory and monetary policy. Estimation of the natural rate of interest, however, has received little attention. We apply the Kalman filter to estimate jointly time-varying natural rates of interest and output and trend growth. We find a close link between the natural rate of interest and the trend growth rate, as predicted by theory. Estimates of the natural rate of interest, however, are very imprecise and subject to considerable real-time measurement error.
Journal of Monetary Economics 50(5), July 2003, 945-975 | With Levin
The existing literature on robust monetary policy rules has largely focused on the case in which the policymaker has a single reference model while the true economy lies within a specified neighborhood of the reference model. In this paper, we show that such rules may perform very poorly in the more general case in which non-nested models represent competing perspectives about controversial issues such as expectations formation and inflation persistence. Using Bayesian and minimax strategies, we then consider whether any simple rule can provide robust performance across such divergent representations of the economy. We find that a robust outcome is attainable only in cases where the objective function places substantial weight on stabilizing both output and inflation; in contrast, we are unable to find a robust policy rule when the sole policy objective is to stabilize inflation. We analyze these results using a new diagnostic approach, namely, by quantifying the fault tolerance of each model economy with respect to deviations from optimal policy.
American Economic Review 93(3), June 2003, 622-645 | With Levin and Wieland
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.
Robust Monetary Policy Rules with Unknown Natural Rates
Brookings Papers on Economic Activity 2002(2), December 2002, 63-145 | With Orphanides
We examine the performance and robustness properties of alternative monetary policy rules in the presence of structural change that renders the natural rates of interest and unemployment uncertain. Using a forward-looking quarterly model of the U.S. economy, estimated over the 1969-2002 period, we show that the cost of underestimating the extent of misperceptions regarding the natural rates significantly exceeds the costs of overestimating such errors. Naive adoption of policy rules optimized under the false presumption that misperceptions regarding the natural rates are likely to be small proves particularly costly.
Our results suggest that a simple and effective approach for dealing with ignorance about the degree of uncertainty in estimates of the natural rates is to adopt difference rules for monetary policy, in which the short-term nominal interest rate is raised or lowered from its existing level in response to inflation and changes in economic activity. These rules do not require knowledge of the natural rates of interest or unemployment for setting policy and are consequently immune to the likely misperceptions in these concepts. To illustrate the differences in outcomes that could be attributed to the alternative policies we also examine the role of misperceptions for the stagflationary experience of the 1970s and the disinflationary boom of the 1990s.
Three Lessons for Monetary Policy in a Low Inflation Era
Journal of Money, Credit, and Banking, November 2000, 936-966 | With Reifschneider
Putty-Clay and Investment: A Business Cycle Analysis
Journal of Political Economy, October 2000, 928-960 | With Gilchrist
Too Much of a Good Thing?
Journal of Economic Growth, March 2000, 65-85 | With Jones
Robustness of Simple Monetary Policy Rules under Model Uncertainty
In Monetary Policy Rules, ed. by Taylor | Chicago: University of Chicago Press, 1999 | With Levin and Wieland
Measuring the Social Return to R&D
Quarterly Journal of Economics, November 1998, 1119-1135 | With Jones