This paper analyzes the effects of portfolio constraints on asset returns and volatility. Portfolio constraints may arise due to minimum capital requirement regulations, margin requirements or leverage constraints on portfolio managers. We analyze how cross-sectional heterogeneity in preferences...

This paper shows that the precautionary motive, combined with asset incompleteness, is a major source of volatility and indeterminacy in financial markets. Price fluctuations originate from agents' efforts to insure themselves through time by borrowing and lending instead of shifting income...

We study transactions that require investments before trading in a competitive market, when forward contracts fixing the transaction price are absent. We show that, despite the market being perfectly competitive and subject to arbitrarily little uncertainty, the inability to jointly determine...

We prove the non-emptiness of the core of an NTU game satisfying a condition of payoff-dependent balancedness, based on transfer rate mappings. We also define a new equilibrium condition on transfer rates and we prove the existence of core payoff vectors satisfying this condition. The additional...

A stumbling block in the modelling of competitive markets with commodity and price spaces of infinite dimensions, arises from having positive cones with an empty interior. This issue precludes the use of tools of differential analysis, ranging from the definition of a derivative, to the use of...

A single condition, limited arbitrage, is shown to be necessary and sufficient for the existence of a competitive equilibrium and the core in economies with any number of markets, finite or infinite, with or without short sales. This extends earlier results of Chichilnisky [8] for finite...

In a smooth pure exchange economy with fixed total resources we investigate whether the smooth selection property holds when endowments are redistributed across consumers through a continuous (non local) redistribution policy. We show that if the policy is regular then there exists a unique...

We study the problem of finding necessary and sufficient conditions that guarantee global uniqueness of equilibria in a pure exchange economy. We show that for every economy to have a unique equilibrium it is necessary and sufficient that (i) there are no critical economies and (ii) a compact...

El objetivo de este ensayo es examinar, en sus méritos y limitaciones, una de las formas del desequilibrio económico de la teoría de Walras, la no unicidad de precios para cada mercancía expresada en su teoría del arbitraje, que lamentablemente constituye el rasgo del desequilibrio menos...

Building on a class of transcendental preferences for luxury, explicit solutions for price taking behavior and exchange equilibrium are discussed, which share the analytical tractability of Cobb-Douglas models and display positive relevance, along the lines discussed by Freixas and Mas-Colell...