We build a model of the financial sector to explain why adverse asset shocks in good economic times lead to a sudden drying up of liquidity. Financial firms raise short-term debt in order to finance asset purchases. When asset fundamentals worsen, debt induces firms to risk-shift; this limits...

Incomplete markets in overlapping generations leave room for Pareto improvement. We analyze a model with two goods and idiosyncratic shocks. We compare market equilibrium with the constrained efficient equilibrium allocation and demonstrate that, when shocks are symmetric and do not affect all...

The aim of this article is to review key issues connected with the structural aspects of the financial system and the resulting financial system models. The structure of the article derives directly from this aim and reflects its review character. First, the structure of the financial system and...

We study the transmission of liquidity shocks from one sector of the economy to other sectors in a general equilibrium model with multiple trading venues connected by profit-seeking arbitrageurs. Arbitrageurs effectively provide liquidity to investors by inter-mediating trades between venues....

We develop a dual-control method for approximating investment strategies in incomplete environments that emerge from the presence of trading constraints. Convex duality enables the approximate technology to generate lower and upper bounds on the optimal value function. The mechanism rests on...

In this Supplement we provide foundations for the asset structures used in the main part of the paper, as well as in Appendix A. We use results by Choquet (1966), Kendall (1962) and Polyrakis (1999) to demonstrate how these asset structures can be generated from a general set of assets available...

This paper studies the efficiency of competitive equilibria in economies where the expansion of investment is facilitated by securitization. We show that the use of se- curitization is generally associated with constrained inefficient aggregate investment, thereby justifying regulatory...

Aggregation is an often used tool in finance and macroeconomics, whereby economic equilibrium in a heterogeneous trader economy is characterized by means of the first order optimality conditions of a representative agent. In this paper we study the conditions under which a representative agent...

Using a standard frictionless, continuous time, and continuous trading stochastic economy with heterogeneous beliefs, the purpose of this paper is to provide sufficient conditions for the existence of competitive equilibrium in an incomplete asset market. A new approach to proving existence is...

We consider an exchange economy with heterogeneous agents and multiple assets and investigate the coupled dynamics of assets' prices and agents' wealth. We assume that agents have heterogeneous beliefs and invest on each asset a fraction of wealth proportional to its expected dividends. Our main...