Research Database

We study optimal fiscal policy in a small open economy (SOE) with sovereign and private default risk and limited commitment to tax plans. The SOE's government uses linear taxation to fund exogenous expenditures and uses public debt to inter-temporally allocate tax distortions. We characterize a class of environments in which the tax on labor goes to zero in the long run, while the tax on capital income may be non-zero, reversing the standard prediction of the Ramsey tax literature. The zero labor tax is an optimal long run outcome if the economy is subject to sovereign debt constraints and the domestic households are impatient relative to the international interest rate. The front loading of tax distortions allows the economy to build a large (aggregate) debt position in the presence of limited commitment. We show that a similar result holds in a closed economy with imperfect inter-generational altruism, providing a link with the closed-economy literature that has explored disagreement between the government and its citizens regarding inter-temporal tradeoffs.

Technology change is modeled as the result of decisions of individuals and groups of individuals to adopt more advanced technologies. The structure is calibrated to the U.S. and postwar Japan growth experiences. Using this calibrated structure we explore how large the disparity in the effective tax rates on the returns to adopting technologies must be to account for the huge observed disparity in per capita income across countries. We find that this disparity is not implausibly large.

We extend the analysis of Kiyotaki and Wright, who study an economy in which the different commodities that serve as media of exchange are determined endogenously. Kiyotaki and Wright consider only symmetric, steady-state, pure-strategy equilibria, and find that for some parameter values no such equilibria exist. We consider mixed-strategy equilibria and dynamic equilibria. We prove that a steady-state equilibrium exists for all parameter values and that the number of steady-state equilibria is generically finite. We also show, however, that there may be a continuum of dynamic equilibria. Further, some dynamic equilibria display cycles.

We develop an asset pricing model with flexible heterogeneity in asset demand across investors, designed to match institutional and household holdings. A portfolio choice model implies characteristics-based demand when returns have a factor structure and expected returns and factor loadings depend on the assets' own characteristics. We propose an instrumental variables estimator for the characteristics-based demand system to address the endogeneity of demand and asset prices. Using U.S. stock market data, we illustrate how the model could be used to understand the role of institutions in asset market movements, volatility, and predictability.

Chile and Mexico experienced severe economic crises in the early 1980s. This paper analyzes four possible explanations for why Chile recovered much faster than did Mexico. Comparing data from the two countries allows us to rule out a monetarist explanation, an explanation based on falls in real wages and real exchange rates, and a debt overhang explanation. Using growth accounting, a calibrated growth model, and economic theory, we conclude that the crucial difference between the two countries was the earlier policy reforms in Chile that generated faster productivity growth. The most crucial of these reforms were in banking and bankruptcy procedures.

This note is intended to introduce economists to a simple SIR model of the progression of COVID-19 in the United States over the next 12-18 months. An SIR model is a Markov model of the spread of an epidemic in a population in which the total population is divided into categories of being susceptible to the disease (S), actively infected with the disease (I), and recovered (or dead) and no longer contagious (R). How an epidemic plays out over time is determined by the transition rates between these three states. This model allows for quantitative statements regarding the tradeoff between the severity and timing of suppression of the disease through social distancing and the progression of the disease in the population. Example applications of the model are provided. Special attention is given to the question of if and when the fraction of active infections in the population exceeds 1% (at which point the health system is forecast to be severely challenged) and 10% (which may result in severe staffing shortages for key financial and economic infrastructure) as well as the cumulative burden of the disease over an 18 month horizon.

Theoretical advances in macroeconomics made in the last three decades have had a major influence on macroeconomic policy analysis. Moreover, over the last several decades, the United States and other countries have undertaken a variety of policy changes that are precisely what macroeconomic theory of the last 30 years suggests. The three key developments that have shaped macroeconomic policy analysis are the Lucas critique of policy evaluation due to Robert Lucas, the time inconsistency critique of discretionary policy due to Finn Kydland and Edward Prescott, and the development of quantitative dynamic stochastic general equilibrium models following Finn Kydland and Edward Prescott.

This paper studies the maturity composition and the term structure of interest rate spreads of government debt in emerging markets. In the data, when interest rate spreads rise, debt maturity shortens and the spread on short-term bonds rises more than the spread on long-term bonds. To account for this pattern, we build a dynamic model of international borrowing with endogenous default and multiple maturities of debt. Long-term debt provides a hedge against future fluctuations in interest rate spreads, while short-term debt is more effective at providing incentives to repay. The trade-off between these hedging and incentive benefits is quantitatively important for understanding the maturity structure in emerging markets. When calibrated to data from Brazil, the model accounts for the dynamics in the maturity of debt issuances and its comovement with the level of spreads across maturities.

In this paper, we show that there is substantial comovement between prices of primary commodities such as oil, aluminum, maize, or copper and real exchange rates between developed economies such as Germany, Japan, and the United Kingdom against the US dollar. We therefore explicitly consider the production of commodities in a two-country model of trade with productivity shocks and shocks to the supplies of commodities. We calibrate the model so as to reproduce the volatility and persistence of primary commodity prices and show that it delivers equilibrium real exchange rates that are as volatile and persistent as in the data. The model rationalizes an empirical strategy to identify the fraction of the variance of real exchange rates that can be accounted for by the underlying shocks, even if those are not observable. We use this strategy to argue that shocks that move primary commodity prices account for a large fraction of the volatility of real exchange rates in the data. Our analysis implies that existing models used to analyze real exchange rates between large economies that mostly focus on trade between differentiated final goods could benefit, in terms of matching the behavior of real exchange rates, by also considering trade in primary commodities.

Doan, Litterman, and Sims (DLS) have suggested using conditional forecasts to do policy analysis with Bayesian vector autoregression (BVAR) models. Their method seems to violate the Lucas critique, which implies that coefficients of a BVAR model will change when there is a change in policy rules. In this paper we construct a BVAR macro model and attempt to determine whether the Lucas critique is important quantitatively. We find evidence following two candidate policy rule changes of significant coefficient instability and of a deterioration in the performance of the DLS method.