New tests of the new-Keynesian Phillips curve

Lagged dependent variables typically play an important role in empirical models of inflation. Do these lags reflect backward-looking inflation expectations, or do they proxy for rational forward-looking expectations, as in the new-Keynesian Phillips curve? Galí and Gertler [1999. Inflation dynamics: a structural econometric analysis. Journal of Monetary Economics 44, 195-222] attempt to answer this question using GMM to estimate specifications incorporating both lagged and future inflation. They report small coefficients on lagged inflation and conclude that the new-Keynesian model provides a good first approximation to inflation dynamics. We show that these tests have low power against alternative backward-looking specifications, and demonstrate that their results are also consistent with a backward-looking Phillips curve. Using an alternative approach, we find that the new-Keynesian pricing model cannot explain the importance of lagged inflation in standard inflation regressions, and find that forward-looking terms play a very limited role in explaining inflation dynamics.     

Optimal monetary policy in an economy with inflation persistence

This paper studies optimal monetary policy in a model where inflation is persistent. Two types of price setters are assumed to exist. One acts rationally given Calvo-type constraints on price setting. The other type sets prices according to a rule-of-thumb. This results in a Phillips curve with both a forward-looking term and a backward-looking term. The Phillips curve nests a standard purely forward-looking Phillips curve as well as a standard purely backward-looking Phillips curve as special cases. A cost push supply shock is derived from microfoundations by adding a time varying income tax and by making the elasticity of substitution between goods stochastic. A central bank loss function for this model is derived from a second-order Taylor approximation of the household's welfare function. Optimal monetary policy for different relative values of the forward- and backward-looking terms is then analyzed for both the commitment case and the case of discretion.     

Intrinsic inflation persistence

Empirical evidence suggests that inflation determination is not purely forward-looking, but models of price setting have struggled to rationalize this finding without directly assuming backward-looking pricing rules for firms. This paper shows that intrinsic inflation persistence can be explained with no deviation from optimizing, forward-looking behaviour if prices that have remained fixed for longer are more likely to be changed than those set recently. A relationship between the probability of price adjustment and the duration of a price spell is shown to imply a simple “hybrid” Phillips curve including lagged and expected inflation, which is estimated using macroeconomic data.     

The New Keynesian Phillips Curve: From Sticky Inflation to Sticky Prices

The New Keynesian Phillips Curve (NKPC) model of inflation dynamics based on forward-looking expectations is of great theoretical significance in monetary policy analysis. Empirical studies, however, often find that backward-looking inflation inertia dominates the dynamics of the short-run aggregate supply curve. This inconsistency is examined by investigating multiple structural changes in the NKPC for the U.S. between 1960 and 2005, employing both inflation expectations survey data and a rational expectations approximation. We find that forward-looking behavior plays a smaller role during the high and volatile inflation regime to 1981 than in the subsequent period of moderate inflation, providing empirical support for sticky price models over the last two decades. A break in the intercept of the NKPC is also identified around 2001 and this may be associated with U.S. monetary policy in that period.     

Estimating New-Keynesian Phillips curves: A full information maximum likelihood approach

The New-Keynesian Phillips curve has recently become an important ingredient in monetary policy models. However, using limited information methods, the empirical support for the New-Keynesian Phillips curve appear to be mixed. This paper argues, by means of Monte Carlo simulations with a simple New-Keynesian sticky price model, that single equations methods, e.g. GMM, are likely to produce imprecise and biased estimates. Then, it is argued that estimating the model with full information maximum likelihood (FIML) is a useful way of obtaining better estimates. Finally, a version of the model used in the Monte Carlo simulations is estimated on U.S. data with FIML and although the pure forward-looking New-Keynesian Phillips curve is rejected, a version with both forward- and backward-looking components provides a reasonable approximation of U.S. inflation dynamics.     

中国MCI指数构建及其反通胀货币政策含义

众多研究表明,我国的菲利普斯曲线是一条兼顾前瞻性和后顾性的新凯恩斯混合型菲利普斯曲线。有鉴于此,本文通过构建新凯恩斯混合菲利普斯曲线模型并基于1994Q1—2010Q3数据估计了我国的标准化和非标准化MCI指数。实证检验表明,新凯恩斯菲利普斯曲线比不合预期的菲利普斯曲线表现出更好的计量经济学特征。本文得到的标准化MCI指数显示,利率变化和;12率变化对通胀的影响力基本相当,但;12率变化对通胀的影响更迅速。本文认为,在利率工具受到制约的通胀背景下,进一步增强人民币汇率弹性,适当利用人民币升值来降低通胀压力,应该是我国反通胀货币政策的一种可行选择。     

Inflation dynamics with search frictions: A structural econometric analysis

The New Keynesian Phillips curve explains inflation dynamics as being driven by current and expected future real marginal costs. In competitive labor markets, the labor share can serve as a proxy for the latter. In this paper, we study the role of real marginal cost components implied by search frictions in the labor market. We construct a measure of real marginal costs by using newly available labor market data on worker finding rates. Over the business cycle, the measure is highly correlated with the labor share. Estimates of the Phillips curve using generalized method of moments reveal that the marginal cost measure remains significant, and that inflation dynamics are mainly driven by the forward-looking component. Bayesian estimation of the full New Keynesian model with search frictions helps us disentangle which shocks are driving the economy to generate the observed unit labor cost dynamics. We find that mark-up shocks are the dominant force in labor market fluctuations.     

Customer markets and the welfare effects of monetary policy

A customer market model in which firms and customers form long-term relations is developed and integrated into the canonical New Keynesian framework. This leads to two important differences compared to the standard model. First, the purely forward-looking Phillips curve is replaced by a hybrid variant where current inflation also depends on past inflation. Second, the welfare cost of inflation is much lower, which leads to an optimal monetary policy where relatively more weight is put on output gap stabilization than previously found in the literature.     

Inflation Dynamics and the New Keynesian Phillips Curve in Four Central European Countries

This paper seeks to shed light on the inflation dynamics of four new central European EU members: the Czech Republic, Hungary, Poland, and Slovakia. To this end, the New Keynesian Phillips curve augmented for open economies is estimated and additional statistical tests applied, with the following results: (1) the claim of New Keynesians that the real marginal cost is the main inflation-forcing variable is fragile, (2) inflation seems to be driven by external factors, and (3) although inflation holds a forward-looking component, the backward-looking component is substantial. An intuitive explanation for higher inflation persistence may be adaptive, rather than rational price setting of local firms.     

Robustness of the estimates of the hybrid New Keynesian Phillips curve

Galí and Gertler [1999. Inflation dynamics: a structural econometric approach. Journal of Monetary Eonomics 44(2), 195-222] developed a hybrid variant of the New Keynesian Phillips curve that relates inflation to real marginal cost, expected future inflation and lagged inflation. GMM estimates of the model suggest that forward-looking behavior is dominant: the coefficient on expected future inflation substantially exceeds the coefficient on lagged inflation. While the latter differs significantly from zero, it is quantitatively modest. Several authors have suggested that our results are the product of specification bias or suspect estimation methods. Here we show that these claims are incorrect, and that our results are robust to a variety of estimation procedures, including GMM estimation of the closed form, and nonlinear instrumental variables. Also, as we discuss, many others have obtained very similar results to ours using a systems approach, including FIML techniques. Hence, the conclusions of GG and others regarding the importance of forward-looking behavior remain robust.     

Do expected future marginal costs drive inflation dynamics?

This article discusses a more general interpretation of the two-step minimum distance estimation procedure proposed in Sbordone (2002). The estimator is again applied to a version of the New Keynesian Phillips curve, where inflation dynamics are driven by the expected evolution of marginal costs. The article clarifies econometric issues, addresses concerns about uncertainty and model misspecification raised in recent studies, and assesses the robustness of previous results. While confirming the importance of forward-looking terms in accounting for inflation dynamics, it suggests how the methodology can be applied to extend the analysis of inflation to a multivariate setting.     

通货膨胀的惯性特征及其货币政策启示

通货膨胀惯性是指通货膨胀在受到随机扰动因素冲击后偏离其长期均衡水平的趋势会持续很久,通常用通胀自回归模型中滞后项系数之和来度量。混合的新凯恩斯主义菲利普斯曲线令人信服地解释了通货膨胀惯性的微观基础,即价格粘性和经济参与人的后视行为。高通货膨胀惯性会削弱货币政策调控的效果,提高中央银行反通胀的社会成本。中央银行承诺在较长时期内钉住一个稳定的名义锚(例如明确或隐性的通货膨胀目标制)则是降低通货膨胀惯性的有效途径。     

The Business Cycle Associated with Exchange Rate-Based Stabilizations

This article examines the effects of disinflation on economicactivity in countries characterized by chronic inflation. Suchcountries have a long history of inflation at rates exceedingthose in industrial countries as well as labor and capital marketsthat have adjusted to function in an inflationary environment.A sample of disinflation programs in several Latin Americancountries and in Israel demonstrates that stabilization effortsin countries with chronic inflation often do not induce theusual Phillips curve tradeoff in the medium run. Specifically,stabilization programs that use the exchange rate as the mainnominal anchor are often associated with a business cycle thatbegins with a boom and ends with a recession. Stabilizationprograms that use money supply as the nominal anchor generallyinduce the expected Phillips curve result: lower inflation isaccompanied by a recession after the program is implemented.     

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.     

通胀—增长权衡和中国菲利普斯曲线的平坦化

近年来发达经济体出现了菲利普斯曲线平坦化现象,但有关中国的研究尚缺乏共识。本文基于实证和理论分析,系统研究了中国菲利普斯曲线的平坦化问题。首先,结合货币政策冲击和月度SVAR框架,发现通胀的响应程度在2010年后大幅下降。由于证据显示总需求曲线并未平坦化,因此通胀响应弱化可解读为菲利普斯曲线的平坦化。数据显示,菲利普斯曲线平坦化与生产率增长放缓同时发生,因此,本文在标准DSGE模型中引入纵向内生增长渠道,该渠道基于研发投入和知识资本积累,从而使生产率内生于经济周期。研究发现:(1)内生增长渠道放大了需求冲击对产出的影响,但缩小了需求冲击对通胀的影响;(2)内生增长渠道改变通胀和增长之间的替代关系,但不改变边际成本向通胀的传导。分段估计显示,2010年后,通胀和增长的关系弱化是边际成本传导变弱和内生增长渠道变强共同作用的结果。本文认为,由于菲利普斯曲线的平坦化,中央银行应继续坚持稳增长和就业优先战略,关注但不必过于担心由此引发的通胀压力。     

A Phillips Curve with Anchored Expectations and Short‐Term Unemployment

This paper examines the behavior of U.S. core inflation, as measured by the weighted median of industry price changes. We find that core inflation since 1985 is well‐explained by an expectations‐augmented Phillips curve in which expected inflation is measured with professional forecasts and labor‐market slack is captured by the short‐term unemployment rate. We also find that expected inflation was backward‐looking until the late 1990s, but then became strongly anchored at the Federal Reserve's target. This shift in expectations changed the relationship between inflation and unemployment from an accelerationist Phillips curve to a level‐level Phillips curve. Our specification explains why high unemployment during the Great Recession did not reduce inflation greatly: partly because inflation expectations were anchored, and partly because short‐term unemployment rose less sharply than total unemployment.     

Inflation Dynamics: The Role of Expectations

This paper estimates the Phillips curve allowing for a simultaneous role of rational and survey expectations. We consider both a reduced form and a structural specification of the Phillips curve. The results suggest that survey expectations can be a statistically significant component of firms' expectations and inflation dynamics. However, rational expectations continue to play a dominant role.     

Predicting inflation expectations: A habit-based explanation under hedging

One of the main challenges monetary policymakers face is predicting the trajectory of short-term inflation, especially considering the consistently flat Phillips curve observed in recent years. A promising approach to tackling this challenge involves modifying the hybrid New Keynesian Phillips curve (HNKPC) by incorporating a hedging factor. This factor accounts for the efforts risk-averse economic agents make to safeguard their spending decisions against uncertainties arising from inflation. Our study provides evidence that the hedging factor plays a crucial role and is a statistically significant predictor of the upcoming year's inflation rate. Specifically, a one-standard-deviation increase in the hedging factor predicts a positive rise in short-term inflation. Furthermore, we demonstrate that the hedging factor significantly determines the common component found in both well-known survey-based and model-based inflation expectation indicators.     

The Phillips curve under state-dependent pricing

We derive a Phillips curve equation from the dynamic stochastic general equilibrium (DSGE) model with state-dependent pricing developed by Dotsey et al. [1999. State-dependent pricing and the general equilibrium dynamics of money and output. Quarterly Journal of Economics 114, 655-690]. This state-dependent Phillips curve encompasses the new Keynesian Phillips curve (NKPC) based on Calvo-type price setting as a special case. We analyze the effect of the state-dependent terms (that is, the variations in the distributions of price vintages) on inflation persistence, and we examine whether the hybrid NKPC (that is, the NKPC extended by a lagged inflation term) can adequately describe inflation dynamics generated in a calibrated state-dependent pricing economy.     

Inflation persistence: Alternative interpretations and policy implications

In this paper, I consider the policy implications of two alternative structural interpretations of observed inflation persistence, which correspond to two alternative specifications of the new Keynesian Phillips curve (NKPC). The first specification allows for some degree of intrinsic persistence by way of a lagged inflation term in the NKPC. The second is a purely forward-looking model, in which expectations farther into the future matter and coefficients are time-varying. In this specification, most of the observed inflation persistence is attributed to fluctuations in the underlying inflation trend, which are a consequence of monetary policy rather than a structural feature of the economy. With a simple quantitative exercise, I illustrate the consequences of implementing monetary policy, assuming a degree of intrinsic persistence that differs from the true one. The results suggest that the costs of implementing a stabilization policy when the policymaker overestimates the degree of intrinsic persistence are potentially higher than the costs of ignoring actual structural persistence; the result is more clear-cut when the policymaker minimizes a welfare-based loss function.