Optimal Monetary Policy in a Small Open Economy with Home Bias

We analyze optimal monetary policy in a small open economy characterized by home bias in consumption. Peculiar to our framework is the application of a Ramsey-type analysis to a model of the recent open-economy New Keynesian literature. We show that home bias in consumption is a sufficient condition for inducing the monetary policymaker of an open economy to deviate from a strategy of strict markup stabilization and contemplate some (optimal) degree of exchange rate stabilization. We focus on the optimal setting of policy both in the case of firms setting prices one period in advance and in a gradual fashion subject to adjustment costs. While the first setup allows us to analytically highlight home bias as an independent source of equilibrium markup variability, the second setup allows to study the effects of future expectations on the optimal policy problem and the effect of home bias on optimal inflation volatility. The latter, in particular, is shown to be related to the degree of trade openness in a U-shaped fashion, whereas exchange rate volatility is monotonically decreasing in openness.     

不同目标制下的中国最优货币政策分析

在更灵活的汇率制度下,中国货币政策会对经济产生什么影响？通过建立一个统一的开放宏观经济模型,发现如果中央银行要实现开放经济下不同目标制的最优货币政策,浮动汇率制成为稳定国内经济,有效应对国内外冲击与实施独立和内向型货币政策的最优选择。     

Optimal fiscal and monetary policy with sticky prices

In this paper I consider the role of state-contingent inflation as a fiscal shock absorber in an economy with nominal rigidities. I study the Ramsey equilibrium in a monetary model with distortionary taxation, nominal non-state-contingent debt, and sticky prices. With sticky prices, the Ramsey planner must balance the shock absorbing benefits of state-contingent inflation against the associated resource misallocation costs. For government spending processes resembling post-war experience, introducing sticky prices generates striking departures in optimal policy from the case with flexible prices. For even small degrees of price rigidity, optimal policy displays very little volatility in inflation. Tax rates display greater volatility compared to the model with flexible prices. With sticky prices, tax rates and real government debt exhibit behavior similar to a random walk. For government spending processes resembling periods of intermittent war and peace, optimal policy displays extreme inflation volatility even when the degree of price rigidity is large. As the variability in government spending increases, smoothing tax distortions across states of nature becomes increasingly important, and the shock absorber role of inflation is accentuated.     

Home bias,exchange rate disconnect,and optimal exchange rate policy

This paper examines how much the central bank should adjust the interest rate in response to real exchange rate fluctuations. The paper first demonstrates, in a two-country Dynamic Stochastic General Equilibrium (DSGE) model, that home bias in consumption is important to replicate the exchange rate volatility and exchange rate disconnect documented in the data. When home bias is high, the shock to Uncovered Interest rate Parity (UIP) can substantially drive up exchange rate volatility while leaving the volatility of real macroeconomic variables, such as GDP, almost untouched. The model predicts that the volatility of the real exchange rate relative to that of GDP increases with the extent of home bias. This relation is supported by the data. A second-order accurate solution method is employed to find the optimal operational monetary policy rule. Our model suggests that the monetary authority should not seek to vigorously stabilize exchange rate fluctuations. In particular, when the central bank does not take a strong stance against the inflation rate, exchange rate stabilization may induce substantial welfare loss. The model does not detect welfare gain from international monetary cooperation, which extends Obstfeld and Rogoff's [Obstfeld, M., Rogoff, K.,2002. Global implications of self-oriented national monetary rules, Quarterly Journal of Economics May, 503–535] findings to a DSGE model.     

Real exchange rate persistence and monetary policy rules

The objective of this paper is to analyze the effects of alternative monetary rules on real exchange rate persistence. Using a two-country stochastic dynamic general equilibrium with nominal price stickiness and local currency pricing, we will show how the persistence of purchasing power parity deviations can be related to a monetary theory of these deviations. When monetary policy lean against the wind, there is no relationship of proportionality between the time during which prices remain sticky and the persistence of the response of the real exchange rate: in this case high nominal price rigidity is not sufficient, per se, in generating any persistence following a monetary shock. Moreover, we emphasize the role of interest rates smoothing policies and relative price stickiness within countries in understanding the relationship between the real exchange rate and monetary shocks. With reasonable parameters values, a wide range of monetary policy rules can generate real exchange rate autocorrelations around the ones observed in the data.     

新凯因斯DSGE模型与货币政策法则之汇率动态分析

对于小型开放经济而言,当经济存在价格僵硬的情况下,中央银行在面对不同冲击发生时,各政策法则执行对汇率波动的影响及动态调整过程差异较大。从中国台湾地区的情况为案例来看,在稳定汇率波动方面:当国内技术冲击时,货币法则优于利率法则;当国外通货膨胀时,利率法则优于货币法则;当国外利率冲击时,执行利率法则或货币法则,其结果无显著差异。在汇率动态调整方面:当国外利率调升时,中央银行执行利率法则与货币法则下,汇率的瞬时反应为过度贬值;当国外物价膨胀时,执行利率法则与货币法则下,汇率的瞬时反应表现为立即升值;当国内技术进步冲击时,因为国外冲击对小型开放经济体系影响力道较强,使得国内技术进度对体系的影响相对较小,其中在利率法则下,汇率微幅贬值,而在货币法则下,汇率微幅升值。     

Optimal simple and implementable monetary and fiscal rules

Welfare-maximizing monetary- and fiscal-policy rules are studied in a model with sticky prices, money, and distortionary taxation. The Ramsey-optimal policy is used as a point of comparison. The main findings are: the size of the inflation coefficient in the interest-rate rule plays a minor role for welfare. It matters only insofar as it affects the determinacy of equilibrium. Optimal monetary policy features a muted response to output. Interest-rate rules that feature a positive response to output can lead to significant welfare losses. The welfare gains from interest-rate smoothing are negligible. Optimal fiscal policy is passive. The optimal monetary and fiscal rule combination attains virtually the same level of welfare as the Ramsey-optimal policy.     

World food prices and monetary policy

How should monetary policy respond to large fluctuations in world food prices? We study this question in an open economy model in which imported food has a larger weight in domestic consumption than abroad and international risk sharing can be imperfect. A key novelty is that the real exchange rate and the terms of trade can move in opposite directions in response to world food price shocks. This exacerbates the policy trade-off between stabilizing output prices vis a vis the real exchange rate, to an extent that depends on risk sharing and the price elasticity of exports. We characterize implications for dynamics, optimal monetary policy, and the relative performance of practical monetary rules. While CPI targeting and expected CPI targeting can dominate PPI targeting if international risk sharing is perfect, even seemingly mild departures from the latter make PPI targeting a winner.     

The Interaction between Capital Requirements and Monetary Policy

The interaction between capital requirements and monetary policy is assessed by means of simple rules in a dynamic general equilibrium model featuring a banking sector. In “normal” times, when economic dynamics are driven by supply shocks, an active use of capital requirements generates modest benefits in terms of volatility of the target variables compared to the case in which only the central bank carries out stabilization policies. The lack of cooperation between the two policymakers may result in excessive volatility of the monetary policy rate and capital requirements. The benefits of introducing capital requirements become sizeable when financial shocks, which affect the supply of loans, are important drivers of economic dynamics; the availability of capital requirements as a policy tool yields a significant gain in terms of macroeconomic stabilization, regardless of the type of interaction between monetary and capital requirements policies.     

Capital controls and monetary policy autonomy in a small open economy

Is there a link between capital controls and monetary policy autonomy in a country with a floating currency? Shocks to capital flows into a small open economy lead to volatility in asset prices and credit supply. To lessen the impact of capital flows on financial instability, a central bank finds it optimal to use the domestic interest rate to “manage” the capital account. Capital account restrictions affect the behavior of optimal monetary policy following shocks to the foreign interest rate. Capital controls allow optimal monetary policy to focus less on the foreign interest rate and more on domestic variables.     

Keynesian Inefficiency and Optimal Policy: A New Monetarist Approach

A simple model of monetary/labor search is constructed to study Keynesian indeterminacy and optimal policy. In the model, economic agents have trouble splitting the surplus from exchange appropriately, and we consider monetary and fiscal policies that correct this Keynesian inefficiency. A Taylor rule neither implies determinacy, nor does it support an efficient outcome. An optimal policy yields an efficient and determinate allocation of resources, but equilibrium policy actions, wages, and prices are indeterminate at the optimum.     

Implications of habit formation for optimal monetary policy

We study the implications for optimal monetary policy of introducing habit formation in consumption into a general equilibrium model with sticky prices. Habit formation affects the model's endogenous dynamics through its effects on both aggregate demand and households’ supply of output. We show that the objective of monetary policy consistent with welfare maximization includes output stabilization, as well as inflation and output gap stabilization. We find that the variance of output increases under optimal policy, even though it acquires a higher implicit weight in the welfare function. We also find that a simple interest rate rule nearly achieves the welfare-optimal allocation, regardless of the degree of habit formation. In this rule, the optimal responses to inflation and the lagged interest rate are both declining in the size of the habit, although super-inertial policies remain optimal.     

Exchange rate pass-through in emerging countries: Do the inflation environment,monetary policy regime and central bank behavior matter?

In this paper, we estimate the exchange rate pass-through (ERPT) to import and consumer prices for a sample of 14 emerging countries over the 1994Q1-2015Q3 period. To this end, we augment the traditional bivariate relationship between the nominal effective exchange rate and inflation by accounting for monetary stability proxied by the inflation environment, monetary policy regime and central bank behavior. We show that both the level and volatility of inflation, as well as adopting an inflation target or the transparency of monetary policy decisions clearly reduce ERPT to consumer prices. However, uncertainty about domestic monetary policy seems less relevant in explaining the pass-through to the price of imports.     

Optimal Monetary Policy Rules and House Prices: The Role of Financial Frictions

We probe the scope for reacting to house prices in simple and implementable monetary policy rules, using a New Keynesian model with a housing sector and financial frictions on the household side. We show that the social‐welfare‐maximizing monetary policy rule features a reaction to house price variations, when the latter are generated by housing demand or financial shocks. The sign and size of the reaction crucially depend on the degree of financial frictions in the economy. When the share of constrained agents is relatively small, the optimal reaction is negative, implying that the central bank must move the policy rate in the opposite direction with respect to house prices. However, when the economy is characterized by a sufficiently high average loan‐to‐value ratio, then it becomes optimal to counter house price increases by raising the policy rate.     

The Cost of Nominal Rigidity in NNS Models

We present a model with Calvo wage and price setting, capital formation, and estimated rules for government spending and monetary policy. Our model captures many aspects of U.S. data, including the volatility that has been observed in various efficiency gaps. We estimate the cost of nominal rigidity—welfare under flexible wages and prices minus welfare with nominal rigidities—to be as much as 3% of consumption each period. Since there are interest rate rules that virtually eliminate this cost, our model suggests that—contrary to Lucas's (2003) assertion—there is considerable room for improvement in demand management policy.     

Systemic risk: A new trade-off for monetary policy?

We introduce time-varying systemic risk (à la He and Krishnamurthy, 2014) in an otherwise standard New-Keynesian model to study whether simple leaning-against-the-wind interest rate rules can reduce systemic risk and improve welfare. We find that while financial sector leverage contains additional information about the state of the economy that is not captured in inflation and output leaning against financial variables can only marginally improve welfare because rules are detrimental in the presence of falling asset prices. An optimal macroprudential policy, similar to a counter cyclical capital requirement, can eliminate systemic risk raising welfare by about 1.5%. Also, a surprise monetary policy tightening does not necessarily reduce systemic risk, especially during bad times. Finally, a volatility paradox a la Brunnermeier and Sannikov (2014) arises when monetary policy tries to excessively stabilize output.     

Optimal exchange rate flexibility with large labor unions

We study the optimal volatility of the exchange rate in a two-country model with sectoral non-atomistic wage setters, non-traded goods, nominal rigidities and alternative pricing assumptions – producer or local currency pricing. Labor unions internalize the sectoral impact of their wage settlements through firms' labor demand. With local currency pricing, exchange rate depreciation raises sales revenue, which in turn boosts domestic consumption and labor demand. Unions anticipate this effect and set higher wages accordingly. With small unions and low wage markup, optimal monetary policy enhances exchange rate movements to improve its terms of trade. With large unions and high wage markup, optimal monetary policy curbs exchange rate movements to restrain inflationary wage demands and to stabilize employment.     

Optimal monetary policy with the cost channel

In the standard new Keynesian framework, an optimizing policy maker does not face a trade-off between stabilizing the inflation rate and stabilizing the gap between actual output and output under flexible prices. An ad hoc, exogenous cost-push shock is typically added to the inflation equation to generate a meaningful policy problem. In this paper, we show that a cost-push shock arises endogenously when a cost channel for monetary policy is introduced into the new Keynesian model. A cost channel is present when firms’ marginal cost depends directly on the nominal rate of interest. Besides providing empirical evidence for a cost channel, we explore its implications for optimal monetary policy. We show that its presence alters the optimal policy problem in important ways. For example, both the output gap and inflation are allowed to fluctuate in response to productivity and demand shocks under optimal monetary policy.     

The Value of Interest Rate Stabilization Policies When Agents Are Learning

We examine the expectational stability (E-stability) of rational expectations equilibrium in the "New Keynesian" model where monetary policy is optimally derived and interest rate stabilization is added to the central bank's traditional objectives of inflation and output stabilization. We consider both the case where the central bank lacks a commitment technology and the case of full commitment. We show that for both cases, optimal policy rules yield rational expectations equilibria that are E-stable for a wide range of empirically plausible parameter values. These findings stand in contrast to Evans and Honkapohja's findings for optimal monetary policy rules in environments where interest rate stabilization is not a central bank objective.