# Research

Working Papers
Aguiar, Mark, Mark Bils, and Corina Boar. “Who are the Hand-to-Mouth?”. Working Papers: n. pag. Print.
Aguiar, Mark, et al.Leisure Luxuries and the Labor Supply of Young Men”. Working Papers: n. pag. Print.
Aguiar, Mark, and Manuel Amador. “Self-Fulfilling Debt Dilution: Maturity and Multiplicity in Debt Models”. Working Papers: n. pag. Print.Abstract

We establish that creditor beliefs regarding future borrowing can be self-fulfilling, leading to multiple equilibria with markedly different debt accumulation patterns. We characterize such indeterminacy in the Eaton-Gersovitz sovereign debt model augmented with long maturity bonds. Two necessary conditions for the multiplicity are: (i) the government is more impatient than foreign creditors, and (ii) there are deadweight losses from default; both are realistic and standard assumptions in the quantitative literature. The multiplicity is dynamic and stems from the self-fulfilling beliefs of how future creditors will price bonds; long maturity bonds are therefore a crucial component of the multiplicity. We introduce a third party with deep pockets to discuss the policy implications of this source of multiplicity and identify the potentially perverse consequences of traditional "lender of last resort" policies.

Aguiar, Mark, et al.Self-Fulfilling Debt Crises, Revisited”. Working Papers: n. pag. Print.Abstract

We revisit self-fulfilling rollover crises by introducing an alternative equilibrium selection that involves bond auctions at depressed but strictly positive equilibrium prices, a scenario in line with observed sovereign debt crises.  We refer to these auctions as desperate deals,'' the defining feature of which is a price schedule that makes the government indifferent to default or repayment.  The government randomizes at the time of repayment, which we show can be implemented in pure strategies by introducing stochastic political payoffs or external bailouts.  Quantitatively, auctions at fire-sale prices are crucial for generating realistic spread volatility.

Submitted
Aguiar, Mark, Manuel Amador, and Stelios Fourakis. “On the Welfare Losses from External Sovereign Borrowing”. Submitted: n. pag. Print.
2019
Aguiar, Mark, and Manuel Amador. “A Contraction for Sovereign Debt Models”. Journal of Economic Theory 183 (2019): , 183, 842-875. Web. Publisher's VersionAbstract
Using a dual representation, we show that the Markov equilibria of the one-period-bond Eaton-Gersovitz (1981) incomplete markets sovereign debt model can be represented as a fixed point of a contraction mapping, providing a new proof of the uniqueness of equilibrium in the benchmark sovereign debt model. The arguments can be extended to incorporate re-entry probabilities after default when the shock process is iid.  Our representation of the equilibrium bears many similarities to an optimal contracting problem.  We use this to argue that commitment to budget rules has no value to a benevolent government. We show how the introduction of long-term bonds breaks the link to the constrained planning problem.
Aguiar, Mark, et al.Take the Short Route: Equilibrium Default and Debt Maturity”. Econometrica 2019423-462. Web. Publisher's VersionAbstract
We study the interactions between sovereign debt default and maturity choice in a setting with limited commitment for repayment as well as future debt issuances. Our main finding is that under a wide range of conditions the sovereign should, as long as default is not preferable, remain passive in long-term bond markets, making payments and retiring long-term bonds as they mature but never actively issuing or buying back such bonds. The only active debt-management margin is the short-term bond market. We show that any attempt to manipulate the existing maturity profile of outstanding long-term bonds generates losses, as bond prices move against the sovereign. Our results hold regardless of the shape of the yield curve. The yield curve captures the average costs of financing at different maturities but is misleading regarding the marginal costs.
2016
Aguiar, Mark, and Erik Hurst. “The Macroeconomics of Time Allocation”. Handbook of Macroeconomics. Elsevier, 2016. Print.Abstract

In this chapter we explore the macroeconomics of time allocation.  We begin with an overview of the trends in market hours in the US, both in the aggregate and for key sub-samples.  After introducing a Beckerian theoretical framework, the chapter then discusses key empirical patterns of time allocation, both in the time series (including business cycle properties) and over the lifecycle.  We focus on several core non-market activities, including home production, childcare, and leisure.  The chapter concludes with a discussion of why these patterns are important to macroeconomics and spells out directions for future research.

Aguiar, Mark, et al.Quantitative Models of Sovereign Debt Crises”. Handbook of Macroeconomics. Elsevier, 2016. Print.Abstract

This chapter is on quantitative models of sovereign debt crises in emerging economies.  We interpret debt crises broadly to cover all of the major problems a country can experience while trying to issue new debt, including default, sharp increases in the spread and failed auctions.  We examine the spreads on sovereign debt of 20 emerging market economies since 1993 and document the extent to which fluctuations in spreads are driven by country-specific fundamentals, common latent factors and observed global factors. Our findings motivate quantitative models of debt and default with the following features: (i) trend stationary or stochastic growth, (ii) risk averse competitive lenders, (iii) a strategic repayment/borrowing decision, (iv) multi-period debt,  (v) a default penalty that includes both a reputation loss and a physical output loss and (vi) rollover defaults.   For the quantitative evaluation of the model, we focus on Mexico and carefully discuss the successes and weaknesses of various versions of the model.  We close with some thoughts on useful directions for future research.

Aguiar, Mark, and Manuel Amador. “Fiscal Policy in Debt Constrained Economies”. Journal of Economic Theory 161 (2016): , 161, 37-75. Web. Publisher's VersionAbstract

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.

2015
Aguiar, Mark, et al.Coordination and Crisis in Monetary Unions”. Quarterly Journal of Economics 130 (2015): , 130, 1727-1779. Web. Publisher's VersionAbstract

We characterize fiscal and monetary policy in a monetary union with the potential for rollover crises in sovereign debt markets. Member-country fiscal authorities lack commitment to repay their debt and choose fiscal policy independently. A common monetary authority chooses inflation for the union, also without commitment. We first describe the existence of a fiscal externality that arises in the presence of limited commitment and leads countries to over borrow; this externality rationalizes the imposition of debt ceilings in a monetary union. We then investigate the impact of the composition of debt in a monetary union, that is the fraction of high-debt versus low-debt members, on the occurrence of self-fulfilling debt crises. We demonstrate that a high-debt country may be less vulnerable to crises and have higher welfare when it belongs to a union with an intermediate mix of high- and low-debt members, than one where all other members are low-debt. This contrasts with the conventional wisdom that all countries should prefer a union with low-debt members, as such a union can credibly deliver low inflation. These findings shed new light on the criteria for an optimal currency area in the presence of rollover crises.

Aguiar, Mark, and Mark Bils. “Has Consumption Inequality Mirrored Income Inequality”. American Economic Review 105 (2015): , 105, 2725-2756. Web. DataAbstract

We revisit to what extent the increase in income inequality over the last 30 years has been mirrored by consumption inequality. We do so by constructing an alternative measure of consumption expenditure, using data from the Consumer Expenditure Survey (CE), that employs a demand system to correct for systematic measurement error. Specifically, we consider trends in the relative expenditure of high-income and low-income households for different goods with different expenditure elasticities. Our estimation exploits the difference in the growth rate of luxury consumption inequality versus necessity consumption inequality. This double-differencing,'' which we implement in a regression framework, corrects for mis-measurement that can systematically vary over time by good and income group. Our results show that consumption inequality has tracked income inequality much more closely than estimated by direct responses on expenditures.

2014
Aguiar, Mark, and Manuel Amador. “Sovereign Debt”. Handbook of International Economics Vol 4. Elsevier, 2014. Print.Abstract

In this chapter, we use a benchmark limited-commitment model to explore key issues in the economics of sovereign debt. After highlighting conceptual issues that distinguish sovereign debt as well as reviewing a number of empirical facts, we use the model to discuss debt overhang, risk sharing, and capital flows in an environment of limited enforcement. We also discuss recent progress on default and renegotiation; self-fulfilling debt crises; and incomplete markets and their quantitative implications. We conclude with a brief assessment of the current state of the literature and highlight some directions for future research.

2013
Aguiar,, et al.Crisis and Commitment: Inflation Credibility and the Vulnerability to Sovereign Debt Crises”. 2013: n. pag. Print.Abstract

We propose a continuous time model of nominal debt and investigate the role of inflation credibility in the potential for self-fulfilling debt crises. Inflation is costly, but reduces the real value of outstanding debt without the full punishment of default. With high inflation credibility, which can be interpreted as joining a monetary union or issuing foreign currency debt, debt is effectively real. By contrast, with low inflation credibility, sovereign debt is nominal and in a debt crisis a government may opt to inflate away a fraction of the debt burden rather than explicitly default. This flexibility potentially reduces the country's exposure to self-fulfilling crises. On the other hand, the government lacks credibility not to inflate in the absence of crisis. This latter channel raises the cost of debt in tranquil periods and makes default more attractive in the event of a crisis, increasing the country's vulnerability. We characterize the interaction of these two forces. We show that there is an intermediate inflation credibility that minimizes the country's exposure to rollover risk. Low inflation credibility brings the worst of both worlds---high inflation in tranquil periods and increased vulnerability to a crisis.

Aguiar,, and Hurst. “Deconstructing Life Cycle Expenditure”. Journal of Political Economy 121.3 (2013): , 121, 3, 437-492. Web. Publisher's VersionAbstract

In this paper we revisit two well-known facts regarding lifecycle expenditures. The first is the familiar hump'' shaped lifecycle profile of nondurable expenditures. The second is that cross-household consumption inequality increases steadily throughout the lifecycle. We document that the behavior of total nondurables masks surprising heterogeneity in the lifecycle profile of individual consumption sub-components. We provide evidence that the categories driving lifecycle consumption are either inputs into market work (clothing and transportation) or are amenable to home production (food). Using a quantitative model, we document that the disaggregated lifecycle consumption profiles imply a level of uninsurable permanent income risk that is similar to that implied by wage data and substantially lower than that implied by a model using only a composite consumption good.

Aguiar,, Hurst, and Karabarbounis. “The Life-Cycle Profile of Time Spent on Job Search”. American Economic Review: Papers and Proceedings 2013: , 111-116. Print.
Aguiar, Mark, Erik Hurst, and Loukas Karabarbounis. “Time Use during the Great Recession”. American Economic Review 103.5 (2013): , 103, 5, 1664-96. Print.Abstract

Using data from the American Time Use Survey between 2003 and 2010, we document that home production absorbs roughly 30 percent of foregone market work hours at business cycle frequencies. Leisure absorbs roughly 50 percent of foregone market work hours, with sleeping and television watching accounting for most of this increase. We document significant increases in time spent on shopping, child care, education, and health. Job search absorbs between 2 and 6 percent of foregone market work hours. We discuss the implications of our results for business cycle models with home production and non-separable preferences.

2012
Aguiar,, Hurst, and Karabarbounis. “Recent Developments in the Economics of Time Use”. Annual Review of Economics 4 (2012): , 4, 373-397. Print.
2011
Aguiar,, and Amador. “Growth in the Shadow of Expropriation”. Quarterly Journal of Economics 126.2 (2011): , 126, 2, 651-697. Print.Abstract

We propose a tractable variant of the open economy neoclassical growth model that emphasizes political economy and contracting frictions. The political economy frictions involve a preference for immediate spending, while the contracting friction is a lack of commitment regarding foreign debt and expropriation. We show that the political economy frictions slow an economy's convergence to the steady state due to the endogenous evolution of capital taxation. The model rationalizes why openness has different implications for growth depending on the political environment, why institutions such as the treatment of capital income evolve over time, why governments in countries that grow rapidly accumulate net foreign assets rather than liabilities, and why foreign aid may not affect growth.

2009
Aguiar,, and Hurst. The Increase in Leisure Inequality: 1965-2005. Washington, DC: American Enterprise Institute, 2009. Web. Publisher's Version
Aguiar,, Amador, and Gopinath. “Investment Cycles and Sovereign Debt Overhang”. Review of Economic Studies 176.1 (2009): , 176, 1, 1-31. Print.Abstract

We characterize optimal taxation of foreign capital and optimal sovereign debt policy in a small open economy where the government cannot commit to policy, seeks to insure a risk averse domestic constituency, and is more impatient than the market. Optimal policy generates long-run cycles in both sovereign debt and foreign direct investment in an environment in which the first best capital stock is a constant. The expected tax on capital endogenously varies with the state of the economy and investment is distorted by more in recessions than in booms, amplifying the effect of shocks. The government's lack of commitment induces a negative correlation between investment and the stock of government debt, a debt overhang'' effect. Debt relief is never Pareto improving and cannot affect the long-run level of investment. Furthermore, restricting the government to a balanced budget can eliminate the cyclical distortion of investment.

Aguiar,, Amador, and Gopinath. “Expropriation Dynamics”. American Economic Review: Papers and Proceedings 2009: , 473-479. Print.
2008
Aguiar,, and Hurst. “Permanent Income Hypothesis”. New Palgrave Dictionary of Economics. Palgrave Macmillan, 2008. Web. Publisher's Version
2007
Aguiar, Mark, and Erik Hurst. “Measuring Trends in Leisure: The Allocation of Time Over Five Decades”. Quarterly Journal of Economics 122.3 (2007): , 122, 3, 969-1006. Web. Data WebsiteAbstract

In this paper, we use five decades of time-use surveys to document trends in the allocation of time within the United States. We find that a dramatic increase in leisure time lies behind the relatively stable number of market hours worked between 1965 and 2003. Specifically, using a variety of definitions for leisure, we show that leisure for men increased by roughly 6‒9 hours per week (driven by a decline in market work hours) and for women by roughly 4‒8 hours per week (driven by a decline in home production work hours). Lastly, we document a growing inequality in leisure that is the mirror image of the growing inequality of wages and expenditures, making welfare calculation based solely on the latter series incomplete.

Aguiar,, and Gopinath. “Emerging Market Business Cycles: The Cycle is the Trend”. Journal of Political Economy 115.1 (2007): , 115, 1, 69-102. Web. Publisher's VersionAbstract

Emerging market business cycles exhibit strongly counter-cyclical current accounts, consumption volatility that exceeds income volatility, and sudden stops'' in capital inflows. These features contrast with developed small open economies. Nevertheless, we show that a standard model characterizes both types of markets. Motivated by the frequent policy regime switches observed in emerging markets, our premise is that these economies are subject to substantial volatility in trend growth. Our methodology exploits the information in consumption and net exports to identify the persistence of productivity. We find that shocks to trend growth--- rather than transitory fluctuations around a stable trend ---are the primary source of fluctuations in emerging markets. The key features of emerging market business cycles are then shown to be consistent with this underlying income process in an otherwise standard equilibrium model.

Aguiar,, and Hurst. “Life-Cycle Prices and Production”. American Economic Review 97.5 (2007): , 97, 5, 1533-1559. Web. Publisher's VersionAbstract

We use scanner data and time diaries to document how households substitute time for money through shopping and home production. We document substantial heterogeneity in prices paid for identical goods for the same area and time, with older households shopping the most and paying the lowest prices. Doubling shopping frequency lowers a good's price by 7 to 10 percent. We estimate the shopper's price of time and use this series to estimate an elasticity of substitution between time and goods in home production of roughly 1.8. The observed life-cycle time allocation implies a consumption series that differs markedly from expenditures.

2006
Aguiar,, and Gopinath. “Emerging Market Fluctuations: The Role of Interest Rate and Productivity Shocks”. Tenth Annual Conference on the Central Bank of Chile: Current Account and External Financing 2006: n. pag. Print.Abstract

In this paper we use a quantitative model to explore the potential frictions that distinguish emerging market business cycles from developed small open economies. Following Aguiar and Gopinath (2007) we allow total factor productivity (TFP) to have a stationary and an integrated component. We also allow for shocks to the consumption and investment Euler Equations that operate through the interest rate. These wedges’’ represent changes in the intertemporal marginal rate of transformation, which may be due to changes in observed interest rates, unobserved borrowing constraints, or other financial frictions. We estimate the model using data from Mexico and Canada. We show that interest rate shocks orthogonal to domestic TFP fail to explain the behavior of emerging markets. We then allow for interest rates to respond to/co-vary with productivity shocks. We find that emerging market business cycles appear to be driven by large shocks to trend income combined with relatively small transitory shocks that co-vary with the interest rate.

Aguiar,, and Broner. “Determining Underlying Macroeconomic Fundamentals during Emerging Market Crises: Are conditions as bad as they seem?”. Journal of Monetary Economics 53.4 (2006): , 53, 4, 699-724. Print.Abstract

Emerging market crises are characterized by large swings in both macroeconomic fundamentals and asset prices. The economic significance of observed movements in macroeconomic variables is obscured by the brief and extreme nature of crises. In this paper we propose to study the macroeconomic consequences of crises by studying the behavior of effective'' fundamentals, constructed by studying the relative movements of stock prices during crises. We find that these effective fundamentals provide a different picture than that implied by observed fundamentals. First, asset prices often reflect expectations of improvement in fundamentals after the initial devaluations; specifically, effective depreciations are positive but not as large as the observed ones. Second, crises vary in their effect on credit market conditions, with investors expecting tightening of credit in some cases (Mexico 1994, Philippines 1997), but loosening of credit in others (Sweden 1992, Korea 1997, Brazil 1999).

Aguiar,, and Gopinath. “Defaultable Debt, Interest Rates, and the Current Account”. Journal of International Economics 69.1 (2006): , 69, 1, 64-83. Print.Abstract

World capital markets have experienced large scale sovereign defaults on a number of occasions. In this paper we develop a quantitative model of debt and default in a small open economy. We use this model to match four empirical regularities regarding emerging markets: defaults occur in equilibrium, interest rates are countercyclical, net exports are countercyclical, and interest rates and the current account are positively correlated. We highlight the role of the stochastic trend in emerging markets, in an otherwise standard model with endogenous default, to match these facts

2005
Aguiar,, and Gopinath. “Fire-Sale FDI and Liquidity Crises”. Review of Economics and Statistics 87.3 (2005): , 87, 3, 439-452. Print.Abstract

In placing capital market imperfections at the center of emerging market crises, the theoretical literature has associated a liquidity crisis with low foreign investment and the exit of investors from the crisis economy. However, a liquidity crisis is equally consistent with an inflow of foreign capital in the form of mergers and acquisitions (M&A). To support this hypothesis, we use a firm-level data set to show that foreign acquisitions increased by 91% in East Asia between 1996 and 1998, while intranational merger activity declined. Firm liquidity plays a significant and sizable role in explaining both the increase in foreign acquisitions and the decline in the price of acquisitions during the crisis. This contrasts with the role of liquidity in noncrisis years and in noncrisis economies in the region. This effect is also most prominent in the tradable sector. Quantitatively, the observed decline in liquidity can explain 25% of the increase in foreign acquisition activity in the tradable sectors. The nature of M&A activity supports liquidity-based explanations of the East Asian crisis and provides an explanation for the puzzling stability of FDI inflows during the crises.

Aguiar,. “Investment, Devaluation, and Foreign Currency Exposure: The Case of Mexico”. Journal of Development Economics 78.1 (2005): , 78, 1, 95-113. Print.Abstract

This paper studies firm-level investment in the wake of the Mexican peso crisis of 1994. While exporters outperform nonexporters in terms of profits and sales after the devaluation, their investment is constrained by weak balance sheets. Specifically, we find that firms with heavy exposure to short-term foreign currency debt before the devaluation experienced relatively low levels of post-devaluation investment. The data also imply that increased sales uncertainty after the peg’s collapse deterred investment, particularly in the tradable sector. The results confirm the recent theoretical literature’s focus on weak balance sheets as driving the recessionary impact of devaluations in emerging markets.

Aguiar,, and Hurst. “Consumption versus Expenditure”. Journal of Political Economy 113.5 (2005): , 113, 5, 919-948. Print.Abstract

Previous authors have documented a dramatic decline in food expenditures at the time of retirement. We show that this is matched by an equally dramatic rise in time spent shopping for and preparing meals. Using a novel data set that collects detailed food diaries for a large cross-section of U.S. households, we show that neither the quality nor the quantity of food intake deteriorates with retirement status. We also show that unemployed households experience a decline in food expenditure and food consumption commensurate with the impact of job displacement on permanent income. These results highlight how direct measures of consumption distinguish between anticipated and unanticipated shocks to income while measures of expenditures obscure the distinction.