We study a labor market equilibrium model in which firms sign optimal long-term contracts with workers. Firms that are financially constrained offer an increasing wage profile: They pay lower wages today in exchange of higher wages once they become unconstrained and operate at a larger scale. In equilibrium, constrained firms are on average smaller and pay lower wages. In this way the model generates a positive relation between firm size and wages. Using data from the National Longitudinal Survey of Youth (NLSY) we show that the key dynamic properties of the model are supported by the data.

Macro developments leading up to the 2008 crisis displayed an unprecedented degree of international synchronization. Before the crisis, all G7 countries experienced credit growth and, around the time of the Lehman bankruptcy, they all faced sharp and large contractions in both real and financial activity. Using a two-country model with financial frictions, we show that a global liquidity shortage induced by pessimistic self-fulfilling expectations can quantitatively generate patterns like those observed in the data. The model also suggests that crises are less frequent with more international financial integration but, when they hit, they are larger and more synchronized across countries.

We document the cyclical properties of US firms' financial flows and show that equity payout is procyclical and debt payout is countercyclical. We then develop a model with debt and equity financing to explore how the dynamics of real and financial variables are affected by “financial shocks.” We find that financial shocks contributed significantly to the observed dynamics of real and financial variables. The recent events in the financial sector show up as a tightening of firms' financing conditions which contributed to the 2008–2009 recession. The downturns in 1990–1991 and 2001 were also influenced by changes in credit conditions.

We study the optimal monetary policy in a two-country open-economy model under two monetary arrangements: (a) multiple currencies controlled by independent policy makers; (b) common currencies with a centralized policy maker. Our findings suggest that: (i) monetary policy competition leads to higher long-term inflation and interest rates with large welfare losses; (ii) the inflation bias and the consequent losses are larger when countries are unable to commit to future policies; (iii) the welfare losses from higher long-term inflation dominates the welfare costs of losing the ability to react optimally to shocks.

Recent studies have shown that the dynamics of firms (growth, job reallocation, and exit) are negatively correlated with the initial size of the firm and its age. In this paper we analyze whether financial factors, in addition to technological differences, are important in generating these dynamics. We introduce financial-market frictions in a basic model of industry dynamics with persistent shocks and show that the combination of persistent shocks and financial frictions can account for the simultaneous dependence of firm dynamics on size (once we control for age) and on age (once we control for size).

We study how cross-country macroeconomic spillovers caused by sovereign default affect equilibrium bailouts. Because of portfolio diversification, the default of one country causes a macroeconomic contraction in other countries, which motivates a bailout. But why do creditor countries choose to bailout debtor countries instead of their own private sector? We show that this is because an external bailout could be cheaper than a domestic bailout. We also show that although anticipated bailouts lead to higher borrowing, they can be Pareto improving not only ex post (after a country has defaulted) but also ex ante (before the country chooses its debt).

We show that a change in organizational structure from partnerships to public companies—which weakens contractual commitment—can lead to higher investment in high return-and-risk activities, higher productivity (value added per employee) and greater income dispersion (inequality). These predictions are consistent with the observed evolution of the financial sector where the switch from partnerships to public companies has been especially important in the decades that preceded the 21st Century financial crisis.

We study the importance of financial markets for (un)employment fluctuations in a model with matching frictions where firms borrow under limited enforcement. Borrowing affects employment through a ‘debt bargaining channel’: higher debt improves the bargaining position of employers with workers and increases the incentive to hire. We estimate the model structurally and find that the debt bargaining channel accounts for 26 percent of unemployment fluctuations. We find empirical support for the channel at the micro level using firm level data from Compustat.

Global financial imbalances can result from financial integration when countries differ in financial markets development. Countries with more advanced financial markets accumulate foreign liabilities in a gradual, long-lasting process. Differences in financial development also affect the composition of foreign portfolios: countries with negative net foreign asset positions maintain positive net holdings of nondiversifiable equity and foreign direct investment. Three observations motivate our analysis: (1) financial development varies widely even among industrial countries, with the United States on top; (2) the secular decline in the U.S. net foreign asset position started in the early 1980s, together with a gradual process of international financial integration; (3) the portfolio composition of U.S. net foreign assets features increased holdings of risky assets and a large increase in debt.

We study a general equilibrium model in which entrepreneurs finance investment with optimal financial contracts. Because of enforceability problems, contracts are constrained efficient. We show that limited enforceability amplifies the impact of technological innovations on aggregate output. This implies that economies with lower enforceability of contracts are characterized by greater macroeconomic volatility. A key assumption for the amplification result is that defaulting entrepreneurs are not excluded from the market.