Knowledge that Transforms

We develop a pure moral hazard model, and a closely related hybrid one, where there are both hidden actions and hidden information, to derive the restrictions from optimal contract theory that characterize set identification. In pure moral hazard models, the expected utility of managers is equalized across states, whereas in a hybrid model the optimal contract equates the expected utility of truth telling with the expected utility of lying. These restrictions are testable. Our identi…cation analysis establishes sharp and tight bounds on the identified set. Our tests and estimators are based on these bounds. We apply semiparametric methods to test the models, estimate the structural parameters, and quantify the effects of hidden actions versus hidden information. The pure moral hazard model is rejected on a large panel data set measuring the compensation of chief executive officers and the …financial and accounting returns of the publicly traded …firms they manage. We do not, however, reject the restrictions of the hybrid model, and our structural estimates for that model show the degree of private information varies considerably across sectors and over fi…rm size.

We estimate the elasticity of exports to credit using matched customs and firm-level bank credit data from Peru. To account for non-credit determinants of exports, we compare changes in exports of the same product and to the same destination by firms borrowing from banks differentially affected by capital-flow reversals during the 2008 financial crisis. We find that credit shocks affect the intensive margin of exports, but have no significant impact on entry or exit of firms to new product and destination markets. Our results suggest that credit shortages reduce exports through raising the variable cost of production, rather than the cost of financing sunk entry investments.

We analyze a large, anonymous labour market in which firms motivate their workers via relational contracts. The market is frictionless and features on-the-job search, in that all acceptable vacancies are immediately filled and the employed compete with the unemployed for vacancies. While firms and workers are ex ante identical, the unique equilibrium exhibits a continuous distribution of contracts in which high wage firms have higher retention rates, more motivated workers and higher productivity. The model thus generates dispersion in wages, productivity and human resource strategies, and gives rise to endogenous job ladders. An exogenous increase in on-the-job search increases the quantity of jobs but decreases their quality; with sufficient on-the-job search there is full employment, and wage dispersion rather than unemployment motivates workers.

In this article we examine the competitive equilibria of a dynamic stochastic economy with complete markets and collateral constraints. We show that, provided the sets of asset pay-offs and of collateral levels are sufficiently rich, the equilibrium allocations with sequential trades and collateral constraints are equivalent to those obtained in Arrow–Debreu markets subject to a series of limited pledgeability constraints. We provide both necessary and sufficient conditions for equilibria to be Pareto efficient and show that when collateral is scarce equilibria are not only Pareto inefficient but also often constrained inefficient, in the sense that imposing tighter borrowing restrictions can make everybody in the economy better off. We derive sufficient conditions for the existence of Markov equilibria and, for the case of two agents, for the existence of equilibria that have finite support. These equilibria can be computed with arbitrary accuracy and the model is very tractable.

Many countries use college-major-specific admissions policies that require a student to choose a college-major pair jointly. Given the potential of student-major mismatches, we explore the equilibrium effects of postponing student choice of major. We develop a sorting equilibrium model under the college-major-specific admissions regime, allowing for match uncertainty and peer effects. We estimate the model using Chilean data. We introduce the counterfactual regime as a Stackelberg game in which a social planner chooses college-specific admissions policies and students make enrollment decisions, learn about their fits to various majors before choosing one. Our estimates indicate that switching from the baseline to the counterfactual regime leads to a 1% increase in average student welfare and that it is more likely to benefit female, low-income and/or low-ability students.

We argue that one major cause of the U.S. post-war baby boom was the rise in female labour supply during World War II. We develop a quantitative dynamic general equilibrium model with endogenous fertility and female labour force participation decisions. We use the model to assess the impact of the war on female labour supply and fertility in the decades following the war. For the war generation of women, the high demand for female labour brought about by mobilization leads to an increase in labour supply that persists after the war. As a result, younger women who reach adulthood in the 1950s face increased labour market competition, which impels them to exit the labour market and start having children earlier. The effect is amplified by the rise in taxes necessary to pay down wartime government debt. In our calibrated model, the war generates a substantial baby boom followed by a baby bust.

We develop a theory of optimal bank leverage in which the benefit of debt in inducing loan monitoring is balanced against the benefit of equity in attenuating risk shifting. However, faced with socially costly correlated bank failures, regulators bail out creditors. Anticipation of this generates multiple equilibria, including one with systemic risk in which banks use excessive leverage to fund correlated, inefficiently risky loans. Limiting leverage and resolving both moral hazards—insufficient loan monitoring and asset substitution—requires a novel two-tiered capital requirement, including a “special capital account” that is unavailable to creditors upon failure.

Asset securitization offers banks the possibility of altering their capital structures and the financial intermediation process. This study shows that the introduction of securitization is associated with fundamental changes in the funding policies of banks. We present evidence of more intense use of securitization by banks with stronger growth opportunities, liquidity constraints, costlier alternative sources of funding, and restricted access to capital markets due to adverse selection. Securitization is observed to be higher in the pecking order of financing choices of small- and medium-sized banks and nonlisted banks, which are likely to face more severe adverse selection problems. (JEL G32, G21) 1.

This review of the literature on the 2007-2009 crisis discusses the precrisis conditions, the crisis triggers, the crisis events, the real effects, and the policy responses to the crisis. The precrisis conditions contributed to the housing price bubble and the subsequent price decline that led to a counterparty-risk crisis in which liquidity shrank due to insolvency concerns. The policy responses were influenced both by the initial belief that it was a market-wide liquidity crunch and the subsequent learning that insolvency risk was a major driver. I suggest directions for future research and possible regulatory changes.

We show that several asset pricing models that rely on long-run risks imply that the state of the economy can be captured by factors derived from the price-dividend ratios of stock portfolios. We find two factors with small growth and large value tilts are important for this purpose, thereby relating the Fama-French model and the Bansal-Yaron and Merton intertemporal asset pricing models. As predicted by the model, these price-dividend ratio factors track consumption volatility and predict future consumption and stock dividends, and the covariance of returns with their innovations explains the cross-section of average returns of several stock portfolios.