We study a discrete-time model of repeated moral hazard without commitment. In every period, a principal finances a project, choosing the scale of the project and a contingent payment plan for an agent, who has the opportunity to appropriate the returns of a successful project unbeknownst the...

We consider the Rothschild-Stiglitz model of insurance but without the exclusivity constraint. It turns out that there always exists a unique equilibrium, in which the reliable and unreliable consumers take out a primary insurance up to its quantity limit, and the unreliable take out further...

We analyze the canonical nonlinear pricing model with limited information. A seller offers a menu with a finite number of choices to a continuum of buyers with a continuum of possible valuations. By revealing an underlying connection to quantization theory, we derive the optimal finite menu for...

Conjugate duality relationships are pervasive in matching and implementation problems and provide much of the structure essential for characterizing stable matches and implementable allocations in models with quasilinear (or transferable) utility. In the absence of quasilinearity, a more...

We study optimal contracting in a setting where a firm repeatedly interacts with multiple workers, and can compensate them based on publicly available performance signals as well as privately reported peer evaluations. If the evaluation and the effort provision are done by different workers (as...

Conjugate duality relationships are pervasive in matching and implementation problems and provide much of the structure essential for characterizing stable matches and implementable allocations in models with quasilinear (or transferable) utility. In the absence of quasilinearity, a more...

We use the theory of abstract convexity to study adverse-selection principal-agent problems and two-sided matching problems, departing from much of the literature by not requiring quasilinear utility. We formulate and characterize a basic underlying implementation duality. We show how this...

I model financial markets that structure decision-making into discrete points separating contract offers, applications, and acceptance/denial decisions. Endogenous beliefs about applicants' risk types emerge as the institutional process extracts private information allowing uninformed firms...

We show how the timing of financial innovation might have contributed to the mortgage boom and then to the bust of 2007-2009. We study the effect of leverage, tranching, securitization and CDS on asset prices in a general equilibrium model with collateral. We show why tranching and leverage tend...

We discuss how leverage can be monitored for institutions, individuals, and assets. While traditionally the interest rate has been regarded as the important feature of a loan, we argue that leverage is sometimes even more important. Monitoring leverage provides information about how risk builds...