Quantifying and sustaining welfare gains from monetary commitment

Our objectives are: to quantify the stabilization welfare gains from commitment; to examine how commitment to an optimal rule can be sustained as an equilibrium; to find a simple interest rate rule that approximates the optimal commitment one. We utilize an empirical micro-founded euro-area DSGE model, a quadratic approximation of household utility as the welfare criterion, employing a nominal interest rate lower bound. In contrast to previous studies, we find significant commitment stabilization gains of around a 0.4-0.5% equivalent permanent consumption increase, and with higher price stickiness gains over 2%. We find that a simple optimized commitment rule responding to inflation and the real wage mimics the optimal one.     

Optimal monetary policy with durable consumption goods

We document that the durable goods sector is much more interest-sensitive than the nondurables sector, and then investigate the implications of these sectoral differences for monetary policy. We formulate a two-sector general equilibrium model that is calibrated both to match the sectoral responses to a monetary shock derived from our empirical VAR and to imply an empirically realistic degree of sectoral output volatility and comovement. While the social welfare function involves sector-specific output gaps and inflation rates, the performance of the optimal policy rule can be closely approximated by a simple rule that targets a weighted average of aggregate wage and price inflation. In contrast, a rule that stabilizes a more narrow measure of final goods price inflation performs poorly in terms of social welfare.     

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.     

Phillips Curve Instability and Optimal Monetary Policy

Empirical evidence suggests the Phillips curve has flattened over the past few decades. To capture this feature of the data, I develop a framework where firms face a changing cost of price adjustment, which produces a Phillips curve with a slope coefficient that varies over time. To evaluate the implications for monetary policy, I construct the utility‐based welfare criterion where the relative weight on output gap deviations changes synchronously with the slope of the Phillips curve. The systematic component of the rule that implements optimal policy is constant under discretion and commitment.     

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.     

Trend inflation, wage and price rigidities, and productivity growth

What are the steady-state implications of inflation in a general-equilibrium model with real per capita output growth and staggered nominal price and wage contracts? Surprisingly, a benchmark calibration implies an optimal inflation rate of -1.9 percent. The analysis also shows that trend inflation has important effects on the economy when combined with nominal contracts and real output growth. Steady-state output and welfare losses are quantitatively important even for low values of trend inflation. Further, nominal wage contracting is found to be quantitatively more important than nominal price contracting in generating the results. This conclusion does not arise from price dispersion per se, but from an effect of nominal output growth on the optimal markup of monopolistically competitive labour suppliers. Finally, accounting for productivity growth is found to be important for calculating the welfare costs of inflation. Indeed, the presence of 2 percent productivity growth increases the welfare costs of inflation in the benchmark specification by a factor of four relative to the no-growth case.     

Price Stability in Economies with Habit Persistence

This paper shows that the divine‐coincidence does not hold in a sticky price model with external habit if a time‐varying tax rate on labor income is not implemented to fully eliminate the time‐varying distortions associated with external habit and monopoly power in goods market. The required labor income tax rate is inversely related to the risk‐free real interest rate and the markup in the goods market, but it is proportional to the degree of external habit. Under this circumstance, the optimal monetary policy commands a countercyclical interest rate, having a perfect negative correlation with tax rate in the sticky price model with external habit. If a time‐invariant tax is the only fiscal instrument, then the degree of external habit entails a gap between the private marginal rate of substitution between consumption and labor and the social marginal rate of substitution, generating an endogenous trade‐off between the stabilization of welfare‐relevant output gap and inflation. Under this circumstance, price stability is not the optimal policy. The monetary policy authority should optimally try to undo the time‐varying distortions associated with external habit and monopoly power in goods market by deviating from price stability.     

Optimal monetary policy in a small open economy with staggered wage and price contracts

We study optimal monetary policy for a small open economy in a model where both domestic prices and wages are sticky due to staggered contracts. The simultaneous presence of the two forms of nominal rigidities introduces an additional trade-off between domestic inflation and the output gap. We derive a second-order approximation to the average welfare losses that can be expressed in terms of the unconditional variances of the output gap, domestic price inflation, and wage inflation. As a consequence, the optimal policy seeks to minimize a weighted average of these variances. We analyze welfare implications of several alternative simple policy rules, and find that domestic price inflation targeting generates relatively large welfare losses, whereas CPI inflation targeting performs nearly as well as the optimal rule.     

Inflation and Welfare in Retail Markets: Prior Production and Imperfectly Directed Search

This paper considers the effect of monetary policy and inflation on retail markets: goods are dated and produced prior to being retailed; buyers direct their search on price and general quality; buyers’ match‐specific tastes are private information. Sellers set the same price for all buyers, some of whom do not value the good highly enough to buy it. The market economy is typically inefficient as a social planner would have the good consumed. Under free entry of sellers, the Friedman rule is optimal policy. When the upper bound on the number of participating sellers binds, moderate levels of inflation can be welfare improving.     

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.     

Robust monetary policy with imperfect knowledge

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 (RE) 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 RE 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.     

Monetary Policy in a Low‐Inflation Environment: Developing a State‐Contingent Price‐Level Target

A number of academic studies find that either price‐level targeting or temporary above‐average inflation are nearly optimal policies to address a liquidity trap crisis. Still, central bankers and the public generally question whether even a temporarily higher inflation rate could be beneficial in addressing a liquidity trap or could be consistent with price stability over the longer term. At the same time, however, the Federal Reserve's projections for high unemployment and low inflation do not seem to be consistent with the best monetary policies to address the Fed's dual mandate responsibilities. Accordingly, it is useful to seriously discuss these potentially beneficial alternative policies.     

Optimal Simple Monetary and Fiscal Rules under Limited Asset Market Participation

The combination of limited asset market participation and consumption habits generates indeterminacy for empirically plausible calibrations of a business cycle model characterized by price and nominal wage rigidities. Equilibrium determinacy is restored by demand management policies based on simple fiscal rules. In this regard, fiscal control of nominal income growth is particularly effective. In addition the complementarity between the Taylor rule and the fiscal feedback on nominal income growth produces relatively large welfare gains, limiting both aggregate and intragroup volatilities.     

Optimal Monetary Policy and Transparency under Informational Frictions

This paper examines the optimal monetary policy and central bank transparency in an economy where firms set prices under informational frictions. The economy is subject to two types of shocks determining the efficient output level and firms' desired markups. To minimize the welfare‐reducing output gap and price dispersion between firms, the central bank controls firms' incentives and expectations by using a monetary instrument and disclosing information on the realized shocks. This paper shows that an optimal policy comprises the disclosure of a linear combination of the two shocks and the adjustment of monetary instruments contingent on the disclosed information.     

Optimal monetary policy with international trade in intermediate inputs

This paper examines optimal monetary policy in a two-country New Keynesian model with international trade in intermediate inputs. We derive the loss function of a cooperative monetary policymaker and find that the optimal monetary policy must target intermediate-goods price inflation rates, final-goods price inflation rates, final-goods output gaps, and relative-price gaps. We use the welfare loss under the optimal monetary policy as a benchmark to evaluate the welfare implications of three Taylor-type monetary policy rules. A main finding is that the degree of price stickiness at the stage of intermediate-goods production is a key factor to determine which policy rule should be followed. Specifically, when the degree of price stickiness at the stage of intermediate-goods production is high, the policymaker should follow intermediate-goods PPI-based Taylor rule, whereas CPI-based Taylor rule should be followed when the degree of price stickiness at the stage of intermediate-goods production is intermediate or low.     

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.     

Financial globalization and monetary policy

Recent data show substantial increases in the size of gross external asset and liability positions. The implications of these developments for optimal conduct of monetary policy are analyzed in a standard open economy model which is augmented to allow for endogenous portfolio choice. The model shows that monetary policy takes on new importance due to its impact on nominal asset returns. Nevertheless, the case for price stability as an optimal monetary rule remains. In fact, it is reinforced. Even without nominal price rigidities, price stability is optimal because it enhances the risk sharing properties of nominal bonds.     

Procurement with specialized firms

We analyze optimal procurement mechanisms when firms are specialized. The procurement agency has incomplete information concerning the firms' cost functions and values high quality as well as low price. Lower type firms are cheaper (more expensive) than higher type firms when providing low (high) quality. With specialized firms, distortion is limited and a mass of types earns zero profits. The optimal mechanism can be inefficient: types providing lower second‐best welfare win against types providing higher second‐best welfare. As standard scoring rule auctions cannot always implement the optimal mechanism, we introduce a new auction format implementing the optimal mechanism.     

Monetary Policy and Asset Prices: A Mechanism Design Approach

We investigate the effects of monetary policy on asset prices in economies where assets are traded periodically in bilateral meetings. The trading mechanism is designed to maximize social welfare taking as given the frictions in the environment and monetary policy. We show that asset price “bubbles” emerge in a constrained‐efficient monetary equilibrium only if liquidity is abundant and the first‐best allocation is implementable. In contrast, if liquidity is scarce, assets are priced at their fundamental value in any constrained‐efficient monetary equilibrium, in which case an increase in inflation has no effect on asset prices, but it reduces output and welfare.     

The value of fiscal discipline for oil-exporting countries

The value of fiscal discipline is assessed by analyzing the role of fiscal policy as a transmission mechanism of oil price shocks in oil-exporting small open economies. Fiscal policy is an important propagation channel. Taking policy as given by the data, the model can successfully explain the responses of key macroeconomic variables, but it is unable to explain these responses under counterfactual fiscal frameworks. Interestingly, fiscal policy also seems capable of regulating the size of pass-through. Furthermore, fiscal policies that insulate the economy from oil price shocks seem to be welfare improving over procyclical ones.