Learning about the Term Structure and Optimal Rules for Inflation Targeting

In this paper, we incorporate the term structure of interest rates in the New Keynesian model and analyze optimal policy under uncertainty about private sector expectations and the degree of inflation persistence. The novel result of our paper is that for large deviations of inflation from its target, the active learning policy is less activist—in the sense of responding less aggressively to the state of the economy—than a myopic policy, which ignores the learning channel. Moreover, for most initial beliefs, the incentive for active learning increases as monetary policy’s leverage over the long‐term interest rate increases.     

Monetary Policy with Heterogeneous and Misspecified Expectations

In the recent literature on monetary policy and learning, it has been suggested that private sector's expectations should play a role in the policy rule implemented by the central bank, as they could improve the ability of the policymaker to stabilize the economy. Private sector's expectations, in these studies, are often taken to be homogeneous and rational, at least in the limit of a learning process. In this paper, instead, we consider the case in which private agents are heterogeneous in their expectations formation mechanisms and hold heterogeneous expectations in equilibrium. We investigate the impact of this heterogeneity in expectations on central bank's policy implementation and on the ensuing economic outcomes, and the general result that emerges is that the central bank should disregard inaccurate private sector expectations and solely base its policy on the accurate ones.     

Adaptive learning, forecast-based instrument rules and monetary policy

This paper argues that recently popular forecast-based instrument rules for monetary policy may fail to stabilize economic fluctuations. In a New Keynesian model of output gap and inflation determination in which private agents face multi-period decision problems, but have non-rational expectations and learn over time, if the monetary authority adopts a forecast-based instrument rule and responds to observed private forecasts then this class of policies frequently induce divergent learning dynamics. A central bank that correctly understands private behavior can mitigate such instability by responding to the determinants of private forecasts. This suggests gathering information on the determinants of expectations to be useful.     

Liquidity provision,interest rates,and unemployment

The effective liquidity supply of the economy—the weighted-sum of all assets that serve as media of exchange—matters for interest rates and unemployment. We formalize this idea by adding an over-the-counter market with collateralized trades to the Mortensen–Pissarides model. An increase in public liquidity through a higher supply of real government bonds raises the real interest rate, crowding out private liquidity and increasing unemployment. If unemployment is inefficiently high, keeping liquidity scarce can be socially optimal. A liquidity crisis affecting the acceptability of private assets as collateral widens the rate-of-return difference between private and public liquidity, also increasing unemployment.     

Price‐Level Targeting and Stabilization Policy

We construct a dynamic stochastic general equilibrium model to study optimal monetary stabilization policy. Prices are fully flexible and money is essential for trade. Our main result is that if the central bank pursues a price‐level target, it can control inflation expectations and improve welfare by stabilizing short‐run shocks to the economy. The optimal policy involves smoothing nominal interest rates that effectively smooths consumption across states.     

Dynamic fiscal policies and unemployment in a simple endogenous growth model

This paper analyzes the growth and employment effects of dynamic fiscal policies in an overlapping generations model with endogenous growth and imperfect labour markets. With balanced-budget policies, the modelled closed economy grows at a constant rate which is higher, the lower are the labour tax rate and the unemployment rate. Constant-flow budget policies are not feasible, while government Ponzi games are feasible only if economic agents have implausibly high savings rates. Furthermore, while constant-stock fiscal policies are sustainable, an increase in the debt-to-capital ratio is accompanied by higher taxes, a rise in unemployment and lower economic growth. JEL Classification E24 · J51 · H63 · O41     

Discretionary monetary policy and the zero lower bound on nominal interest rates

Ignoring the existence of the zero lower bound on nominal interest rates one considerably understates the value of monetary commitment in New Keynesian models. A stochastic forward-looking model with an occasionally binding lower bound, calibrated to the U.S. economy, suggests that low values for the natural rate of interest lead to sizeable output losses and deflation under discretionary monetary policy. The fall in output and deflation are much larger than in the case with policy commitment and do not show up at all if the model abstracts from the existence of the lower bound. The welfare losses of discretionary policy increase even further when inflation is partly determined by lagged inflation in the Phillips curve. These results emerge because private sector expectations and the discretionary policy response to these expectations reinforce each other and cause the lower bound to be reached much earlier than under commitment.     

Imperfect credibility and the zero lower bound

As the nominal interest rate cannot fall below zero, a central bank with imperfect credibility faces a significant challenge to stabilize the economy in a New Keynesian model during a large recession. We characterize the optimal monetary policy at the zero lower bound for the nominal interest rate if credibility is imperfect. Confronting monetary policy communication of the U.S. Federal Reserve and the Swedish Riksbank with such a framework, the credibility of both institutions is shown to have been low in the aftermath of the 2008 economic crisis.     

Robustly optimal monetary policy in a microfounded New Keynesian model

We consider optimal monetary stabilization policy in a New Keynesian model with explicit microfoundations, when the central bank recognizes that private-sector expectations need not be precisely model-consistent, and wishes to choose a policy that will be as good as possible in the case of any beliefs close enough to model-consistency. We show how to characterize robustly optimal policy without restricting consideration a priori to a particular parametric family of candidate policy rules. We show that robustly optimal policy can be implemented through commitment to a target criterion involving only the paths of inflation and a suitably defined output gap, but that a concern for robustness requires greater resistance to surprise increases in inflation than would be considered optimal if one could count on the private sector to have “rational expectations.”     

Monetary policy when potential output is uncertain: Understanding the growth gamble of the 1990s

The Fed kept interest rates low and essentially unchanged during the late 1990s despite a booming economy and record-low unemployment. These interest rates were accommodative by historical standards. Nonetheless, inflation remained low. How did the Fed succeed in sustaining rapid economic growth without fueling inflation and inflationary expectations? In retrospect, it is evident that the productive capacity of the economy increased. Yet as events unfolded, there was uncertainty about the expansion of the capacity of the economy and therefore about the sustainability of the Fed's policy.This paper provides an explanation for the success of the Fed in accommodating growth with stable inflation in the late 1990s. It shows that if the central bank is committed to reverse policy errors it makes because of unwarranted optimism, inflation can remain in check even if the central bank keeps interest rates low because of this optimism. In particular, a price level target—which is a simple way to model a commitment to offset errors—can serve to anchor inflation even if the public does not share the central bank's optimism about shifts in potential output. The paper shows that price level targeting is superior to inflation targeting in a wide range of situations. The paper also provides econometric evidence that, in contrast to earlier periods, the Fed has recently put substantial weight on the price level in setting interest rates. Moreover, it shows that CPI announcement surprises lead to reversion in the price level. Finally, it provides textual evidence that Alan Greenspan puts relatively more weight on the price level than inflation.     

Inflation Targeting,Recursive Inattentiveness,and Heterogeneous Beliefs

We consider a monetary authority that provides an explicit inflation target in order to align expectations with the policy objective. However, biased perceptions of the target may arise due to imperfect information flows. We allow agents to revise expectations over time and we model their recursive choice among prediction strategies as an optimization problem under rational inattention. We then investigate whether a simple policy rule can steer the economy toward the targeted equilibrium. Our findings suggest that determinacy under rational expectations may not be sufficient to reach the target. Instead, monetary policy should be fine‐tuned to correct agents' biased beliefs.     

The role of expectations in stabilization policy

This paper develops and tests a theory of the process by which private agents in an economy form expectations about government policy. Agents form and update their beliefs about the true state of government policy in a Bayesian fashion. The ‘credibility’ of a policy is defined to be the subjective probability that the government is pursuing a 'reform' policy rule. The ‘credibility’ of a reform of monetary or exchange rate policies is a function of the parameters of both monetary and fiscal policies. The theory is applied to the Chilean and Argentine exchange reforms of the late 1970's.     

Anticipated fiscal policy and adaptive learning

The impact of anticipated policy changes when agents form expectations using adaptive learning rather than rational expectations is considered. Agents are assumed to combine limited structural knowledge with a standard adaptive learning rule. These issues are analyzed using two well-known set-ups, an endowment economy and the Ramsey model. In our scenario there are important deviations from both rational expectations and purely adaptive learning. The approach could be applied to other frameworks.     

Time inconsistency as a rationale for public unemployment insurance

A role for public unemployment insurance is developed based on the inability of the government to commit to a future rate of unemployment. This is illustrated using a model in which a minimum wage policy combined with unemployment insurance is welfare-improving. Unemployment insurance could be decentralized to the private sector if the government could commit to a minimum wage. However, if not, a government that acts in the interest of the workers will have an incentive to increase the minimum wage to exploit private insurers. In the absence of commitment, an equilibrium with private unemployment insurance will not exist.     

Discretionary monetary policy and inflation persistence

Rational expectations models of staggered price/wage contracts have failed to replicate the observed persistence in inflation and unemployment during disinflationary periods. The current literature on this persistency puzzle has focused on augmenting the nominal contract model with imperfect credibility and learning. In this paper, I re-examine the persistency puzzle by focusing on the discretionary nature of monetary policy. I show that when the central bank is allowed to re-optimize a quadratic loss function each period, imperfect credibility and learning, even in the absence of staggered contracts, can generate a significant amount of inflation persistence and employment losses during a disinflationary period.     

Heterogeneous Expectations,Optimal Monetary Policy,and the Merit of Policy Inertia

The design and analysis of optimal monetary policy is usually guided by the paradigm of homogeneous rational expectations. Instead, we examine the dynamic consequences of design and implementation strategies, when the actual economy features expectational heterogeneity. Agents have either rational or adaptive expectations. Consequently, the central bank's ability to achieve price stability under heterogeneous expectations depends on its objective and implementation strategy. An expectations‐based reaction function, which appropriately conditions on private sector expectations, performs exceptionally well. However, once the objective introduces policy inertia, popular strategies have similar determinacy properties, but they are less operational. This finding calls for new implementation strategies under interest rate stabilization.     

Sterilization of short-term capital inflows—through lower interest rates?

Reductions in international interest rates are a major cause of capital flows to emerging economies. Increases in domestic interest rates are a frequent policy response to the resulting price increases. This is often unsuccessful. The paper suggests a theoretical explanation based on distinctive features of emerging financial markets, including imperfect asset substitutability and imperfect capital mobility for some sectors of the economy. It concludes that the appropriate policy response to capital inflows may be lower interest rates.     

Instrument instability and short-term monetary control

The literature on instrument instability tends support to a policy of smoothing interest rates: it contends that rigid adherence to a monetary rule would bring about explosive interest-rate movements. This contention is examined using a simple model which incorporates rational expectations; the results suggest that instrument instability is associated with interest-rate smoothing rather than with short-term control of the money supply. Furthermore, policy that attempts to stabilize interest rates may itself account for empirical findings which have hitherto been viewed as evidence that instrument instability would occur if the money supply were closely controlled.     

The Evolution of Security Designs

We consider a competitive and perfect financial market in which agents have heterogeneous cash flow valuations. Instead of assuming that agents are endowed with rational expectations, we model their behavior as the product of adaptive learning. Our results demonstrate that adaptive learning affects security design profoundly, with securities mispriced even in the long run and optimal designs trading off underpricing against intrinsic value maximization. The evolutionary dominant security design calls for issuing securities that engender large losses with a small but positive probability, but that otherwise produce stable payoffs, almost the exact opposite of the pure state claims that are optimal in the rational expectations framework.