Danilov, Vladimir and Koshovoy, Gleb and Page, Frank and Wooders, Myrna (2011): Existence of equilibrium with unbounded short sales: A new approach.

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Abstract
We introduce a new approach to showing existence of equilibrium in models of economies with unbounded short sales. Inspired by the pioneering works of Hart (1974) on asset market models, Grandmont (1977) on temporary economic equilibrium, and of Werner (1987) on general equilibrium exchange economies, all papers known to us stating conditions for existence of equilibrium with unbounded short sales place conditions on recession cones of agents' preferred sets or, more recently, require compactness of the utility possibilities set.. In contrast, in this paper, we place conditions on the preferred sets themselves. Roughly, our condition is that the sum of the weakly preferred sets is a closed set. We demonstrate that our condition implies existence of equilibrium. In addition to our main theorem, we present two theorems showing cases to which our main theorem can we applied. We also relate our condition to the classic condition of Hart (1974).
Item Type:  MPRA Paper 

Original Title:  Existence of equilibrium with unbounded short sales: A new approach 
English Title:  Existence of equilibrium with unbounded short sales: A new approach 
Language:  English 
Keywords:  arbitrage; unbounded short sales; asset market models; sum of weakly preferred sets; existence of equilibrium 
Subjects:  D  Microeconomics > D5  General Equilibrium and Disequilibrium > D53  Financial Markets D  Microeconomics > D5  General Equilibrium and Disequilibrium > D50  General D  Microeconomics > D4  Market Structure, Pricing, and Design > D40  General 
Item ID:  37778 
Depositing User:  Myrna Wooders 
Date Deposited:  31. Mar 2012 22:35 
Last Modified:  18. Feb 2013 12:09 
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URI:  https://mpra.ub.unimuenchen.de/id/eprint/37778 