Individual Versus Aggregate Collateral Constraints and the Overborrowing Syndrome

This paper compares the equilibrium dynamics of an economy facing an aggregate collateral constraint on external debt to the dynamics of an economy facing a collateral constraint imposed at the level of each individual agent. The aggregate collateral constraint is intended to capture an environment in which foreign investors base their lending decisions predominantly upon macro indicators as opposed to individual abilities to pay. Individual agents do not internalize the aggregate borrowing constraint. Instead, in this economy a country interest-rate premium emerges to clear the financial market. The central finding of the paper is that the economy with the aggregate borrowing limit does not generate higher levels of debt than the economy with the individual borrowing limit. That is, there is no overborrowing in equilibrium.

A fiscal theory of sovereign risk

This paper presents a fiscal theory of sovereign risk and default. Under certain monetary-fiscal regimes, the risk of default, and thus the emergence of sovereign risk premia, are inevitable. The paper characterizes the equilibrium processes of the sovereign risk premium and the default rate under a number of alternative monetary policy arrangements. It is argued that, given the fiscal stance, monetary policy plays a crucial role in shaping the equilibrium behaviour of the country risk premium and the default rate. For instance, under some of the monetary policy rules considered, the expected default rate and the sovereign risk premium are zero (and therefore unforecastable) although the government defaults regularly. Under other monetary regimes the default rate and the sovereign risk premium are serially correlated (and therefore forecastable). In addition, environments are characterized under which delaying default is counterproductive. JEL Classification: E6, F4

Optimal simple and implementable monetary and fiscal rules

This paper computes welfare-maximizing monetary and fiscal policy rules in a real business cycle model augmented with sticky prices, a demand for money, taxation, and stochastic government consumption. We consider simple feedback rules whereby the nominal interest rate is set as a function of output and inflation and taxes are set as a function of total government liabilities. We implement a second-order accurate solution to the model. We have several main findings. First, 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. Second, optimal monetary policy features a muted response to output. More importantly, interest rate rules that feature a positive response to output can lead to significant welfare losses. Third, the welfare gains from interest rate smoothing are negligible. Fourth, optimal fiscal policy is passive. Finally, the optimal monetary and fiscal rule combination attains virtually the same level of welfare as the Ramsey optimal policy.

Optimal Simple and Implementable Monetary and Fiscal Rules: Expanded Version

This paper computes welfare-maximizing monetary and fiscal policy rules in a real business cycle model augmented with sticky prices, a demand for money, taxation, and stochastic government consumption. We consider simple feedback rules whereby the nominal interest rate is set as a function of output and inflation, and taxes are set as a function of total government liabilities. We implement a second-order accurate solution to the model. Our main findings are: First, 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. Second, optimal monetary policy features a muted response to output. More importantly, interest rate rules that feature a positive response to output can lead to significant welfare losses. Third, the welfare gains from interest-rate smoothing are negligible. Fourth, optimal fiscal policy is passive. Finally, the optimal monetary and fiscal rule combination attains virtually the same level of welfare as the Ramsey optimal policy.

Optimal Inflation Stabilization in a Medium-Scale Macroeconomic Model

This paper characterizes Ramsey-optimal monetary policy in a medium-scale macroeconomic model that has been estimated to fit well postwar U.S. business cycles. We find that mild deflation is Ramsey optimal in the long run. However, the optimal inflation rate appears to be highly sensitive to the assumed degree of price stickiness. Within the window of available estimates of price stickiness (between 2 and 5 quarters) the optimal rate of inflation ranges from -4.2 percent per year (close to the Friedman rule) to -0.4 percent per year (close to price stability). This sensitivity disappears when one assumes that lump-sum taxes are unavailable and fiscal instruments take the form of distorting income taxes. In this case, mild deflation emerges as a robust Ramsey prediction. In light of the finding that the Ramsey-optimal inflation rate is negative, it is puzzling that most inflation-targeting countries pursue positive inflation goals. We show that the zero bound on the nominal interest rate, which is often cited as a rationale for setting positive inflation targets, is of no quantitative relevance in the present model. Finally, the paper characterizes operational interest-rate feedback rules that best implement Ramsey-optimal stabilization policy. We find that the optimal interest-rate rule is active in price and wage inflation, mute in output growth, and moderately inertial. This rule achieves virtually the same level of welfare as the Ramsey optimal policy.

Policy implications of the New Keynesian Phillips curve

This article surveys recent advancements in the theory of optimal monetary policy in models with a New Keynesian Phillips curve. It identifies four policy implications. First, near price stability is optimal. Second, simple interest rate feedback rules that respond aggressively to price inflation deliver near-optimal equilibrium allocations. Third, interest rate rules that respond to deviations of output from trend may carry significant welfare costs. Fourth, the zero bound on nominal interest rates does not appear to be a significant obstacle for the actual implementation of low and stable inflation.Inflation (Finance) ; Phillips curve

Anticipated Ramsey reforms and the uniform taxation principle: the role of international financial markets

This paper studies the role of asset-market completeness for the properties of optimal fiscal and monetary policy. A suitable framework for this purpose is the small open economy with complete international asset markets. For in this environment changes in policy represent country-specific risk diversifiable in world markets. Our main finding is that the fundamental public finance principle whereby when taxes on all final goods are available, it is optimal to tax final goods uniformly fails to obtain. In general, uniform taxation is optimal because it amounts to a non-distorting tax on fixed factors of production. In the open economy this principle fails because when households can insure against the risk of a policy reform, initial private asset holdings are contingent on actual policy and thus no longer represent an inelastically supplied source of income. Furthermore optimal consumption and income taxes do not respond to government purchases shocks and the Friedman rule is optimal only if the Ramsey planner has access to consumption taxes. JEL Classification: F41, E52, E61, E63

Optimal fiscal and monetary policy in a medium-scale macroeconomic model

In this paper, we study Ramsey-optimal fiscal and monetary policy in a mediumscale model of the U.S. business cycle. The model features a rich array of real and nominal rigidities that have been identified in the recent empirical literature as salient in explaining observed aggregate fluctuations. The main result of the paper is that price stability appears to be a central goal of optimal monetary policy. The optimal rate of inflation under an income tax regime is half a percent per year with a volatility of 1.1 percent. This result is surprising given that the model features a number of frictions that in isolation would call for a volatile rate of inflation—particularly nonstate-contingent nominal public debt, no lump-sum taxes, and sticky wages. Under an income-tax regime, the optimal income tax rate is quite stable, with a mean of 30 percent and a standard deviation of 1.1 percent. JEL Classification: E52, E61, E63Inflation Stabilization, Nominal and Real Rigidities, Ramsey Policy, tax smoothing, Time to Tax

Real Business Cycles in Emerging Countries?

We use more than one century of Argentine and Mexican data to estimate the structural parameters of a small-open-economy real-business-cycle model driven by nonstationary productivity shocks. We find that the RBC model does a poor job at explaining business cycles in emerging countries. We then estimate an augmented model that incorporates shocks to the country premium and financial frictions. We find that the estimated financial-friction model provides a remarkably good account of business cycles in emerging markets and, importantly, assigns a negligible role to nonstationary productivity shocks.