Did the Great Inflation occur despite policymaker commitment to a Taylor rule?

The authors study the hypothesis that misperceptions of trend productivity growth during the onset of the productivity slowdown in the United States caused much of the great inflation of the 1970s. They use the general equilibrium, sticky price framework of Woodford (2002), augmented with learning using the techniques of Evans and Honkapohja (2001). The authors allow for endogenous investment as well as explicit, exogenous growth in productivity and the labor input. They assume the monetary policymaker is committed to using a Taylor-type policy rule. The authors study how this economy reacts to an unexpected change in the trend productivity growth rate under learning. They find that a substantial portion of the observed increase in inflation during the 1970s can be attributed to this source.Equilibrium (Economics) ; Monetary policy ; Macroeconomics ; Inflation (Finance) ; Productivity

Central Bank Communication and Expectations Stabilization

This paper analyzes the value of communication in the implementation of monetary policy. The central bank is uncertain about the current state of the economy. Households and firms are uncertain about the statistical properties of aggregate variables, including nominal interest rates, and must learn about their dynamics using historical data. Given these uncertainties, when the central bank implements optimal policy, the Taylor principle is not sufficient for macroeconomic stability: for reasonable parameterizations self-fulfilling expectations are possible. To mitigate this instability, three communication strategies are contemplated: i) communicating the precise details of the monetary policy -- that is, the variables and coefficients; ii) communicating only the variables on which monetary policy decisions are conditioned; and iii) communicating the inflation target. The first two strategies restore the Taylor principle as a sufficient condition for stabilizing expectations. In contrast, in economies with persistent shocks, communicating the inflation target fails to protect against expectations driven fluctuations. These results underscore the importance of communicating the systematic component of monetary policy strategy: announcing an inflation target is not enough to stabilize expectations -- one must also announce how this target will be achieved.

Did the Great Inflation occur despite policymaker commitment to a Taylor rule?

We study the hypothesis that misperceptions of trend productivity growth during the onset of the productivity slowdown in the U.S. caused much of the great inflation of the 1970s. We use the general equilibrium, sticky price framework of Woodford (2003), augmented with learning using the techniques of Evans and Honkapohja (2001). We allow for endogenous investment as well as explicit, exogenous growth in productivity and the labor input. We assume the monetary policymaker is committed to using a Taylortype policy rule. We study how this economy reacts to an unexpected change in the trend productivity growth rate under learning. We find that a substantial portion of the observed increase in inflation during the 1970s can be attributed to this source.Monetary policy ; Productivity

When does determinacy imply expectational stability?

In the recent literature on monetary and fiscal policy design, adoption of policies that induce both determinacy and learnability of equilibrium has been considered fundamental to economic stabilization. We study the connections between determinacy of rational expectations equilibrium, and expectational stability or learnability of that equilibrium, in a general class of purely forward-looking models. We ask what types of economic assumptions drive differences in the necessary and sufficient conditions for the two criteria. We apply our result to a relatively general New Keynesian model. Our framework is sufficiently flexible to encompass lags in information, a cost channel for monetary policy, and either Euler equation or infinite horizon approaches to learning. We are able to isolate conditions under which determinacy does and does not imply learnability, and also conditions under which long horizon forecasts make a clear difference to conclusions about expectational stability. The sharpest result is that informational delays break equivalence connections between determinacy and learnability.Rational expectations (Economic theory)

Does Central Bank Transparency Matter for Economic Stability

This paper studies the impact of monetary policy transparency on economic stability, when economic agents are boundedly rational. I first consider a simple class of microfunded general equilibrium models with nominal rigidities and learning. Under a transparent monetary regime, market participants have information about how monetary policy is conducted and use it when forming their forecasts. The paper shows that under plausible assumptions about the model environment, a transparent implementation of simple policy rules improves stability under learning dynamics. It is also shown that, independently of the degree of central bank transparency, the Taylor Principle is generally not sufficient to guarantee robustness of the rational expectations equilibrium to expectational mistakes by the central bank or the private sector. The paper also attempts an evaluation of the benefits of transparency using a calibrated model of US datalearnability, inflation targeting, simple feedback rules, endogenous fluctuations

Monetary policy rules and economic stability when agents must learn

In most economic models used for theoretical exploration or policy analysis, there is a crucial role for agents' expectations about future outcomes. Generally, it is assumed that economic agents take their decisions according to rationality principles and that they have a fairly accurate knowledge about the economic environment. In other words, they are assumed to know the model of the economy (Rational Expectations Hypothesis). The latter assumption is somewhat extreme, given the evident lack of agreement, even among professionals, about the correct model of the economy. In this thesis I maintain the hypothesis that agents take their decisions rationally, i. e. in order to maximize their utilities given their budget constraints, but I assume that each agent has to learn about the economic environment. More specifically, I consider economic models for monetary policy analysis. The goal is to study how the introduction of learning in these models can affect the design of monetary policy. Policy recommendations that might be sound under Rational Expectations, might lead to disastrous results under learning. I also use learning as a selection device. Some economic models fail to predict a unique Rational Expectations Equilibrium. Nevertheless, a REE is a sensible prediction of the model only if it can be shown that it is the result of some learning process of the economic agents. REE that are unstable under learning are not plausible equilibria

CONDI: a cost-of-nominal-distortions index

We construct a price index with weights on the prices of different PCE goods chosen to minimize the welfare costs of nominal distortions: a cost-of-nominal-distortions index (CONDI). We compute these weights in a multisector New Keynesian model with time-dependent price setting, calibrated using U.S. data on the dispersion of price stickiness and labor shares across sectors. We find that the CONDI weights mostly depend on price stickiness and are less affected by the dispersion in labor shares. Moreover, CONDI stabilization leads to negligible welfare losses compared to the optimal policy and is better approximated by core rather than headline inflation targeting. An even better approximation of the CONDI can be obtained with an adjusted core index that covers total expenditures excluding autos, clothing, energy, and food at home, but that includes food away from home.Inflation (Finance) ; Price indexes ; Monetary policy

Central bank communication and expectations stabilization

The value of communication in monetary policy is analyzed in a model in which expectations need not be consistent with central bank policy - and, therefore, "unanchored" - because agents face difficult forecasting problems. When the central bank implements optimal policy without communication, the Taylor principle is not sufficient for macroeconomic stability: expectations are unanchored and self-fulfilling expectations are possible. To mitigate this instability, three communication strategies are contemplated to ensure consistency between private forecasts and monetary policy strategy: i) communicating the precise details of the monetary policy - that is, the variables and coefficients; ii) communicating only the variables on which monetary policy decisions are conditioned; and iii) communicating the inflation target. The first two strategies restore the Taylor principle as a sufficient condition for anchoring expectations. In contrast, in economies with persistent shocks, communicating the inflation target fails to protect against expectations driven fluctuations. These results underscore the importance of communicating the systematic component of monetary policy strategy: announcing an inflation target is not enough to stabilize expectations - one must also announce how this target will be achieved

Expectations, Learning and Business Cycle Fluctuations

This paper develops a theory of expectations-driven business cycles based on learning. Agents have incomplete knowledge about how market prices are determined and shifts in expectations of future prices affect dynamics. In a real business cycle model, the theoretical framework amplifies and propagates technology shocks. Improved correspondence with data arises from dynamics in beliefs being themselves persistent and because they generate strong intertemporal substitution effects in consumption and leisure. Output volatility is comparable with a rational expectations analysis with a standard deviation of technology shock that is 20 percent smaller, and has substantially more volatility in investment and hours. Persistence in these series is captured, unlike in standard models. Inherited from real business cycle theory, the benchmark model suffers a comovement problem between consumption, hours, output and investment. An augmented model that is consistent with expectations-driven business cycles, in the sense of Beaudry and Portier (2006), resolves these counterfactual predictions.

Labor Supply Heterogeneity and Macroeconomic Co-movement

Standard real-business-cycle models must rely on total factor productivity (TFP) shocks to explain the observed co-movement between consumption, investment and hours worked. This paper shows that a neoclassical model consistent with observed heterogeneity in labor supply and consumption, can generate co-movement in absence of TFP shocks. Intertemporal substitution of goods and leisure induces co-movement over the business cycle through heterogeneity in consumption behavior of employed and unemployed workers. The result is due to two model features that are introduced to capture important characteristics of US labor market data. First, individual consumption is affected by the number of hours worked with employed consuming more on average than unemployed. Second, changes in the employment rate, a central explanator of total hours variation, then affects aggregate consumption. Demand shocks --- such as shifts in the marginal efficiency of investment, government spending shocks and news shocks --- are shown to generate economic fluctuations consistent with observed business cycles.