Covarrubias, Enrique (2013): Global invertibility of excess demand functions.

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Abstract
In this paper we provide necessary and sufficient conditions for the excess demand function of a pure exchange economy to be globally invertible so that there is a unique equilibrium. Indeed, we show that an excess demand function is globally invertible if and only if its Jacobian never vanishes and it is a proper map. Our result includes as special cases many partial results found in the literature that imply global uniqueness including GaleNikaido conditions and properties related to stability of equilibria. Furthermore, by showing that the condition is necessary, we are implicitly finding the weakest possible condition.
Item Type:  MPRA Paper 

Original Title:  Global invertibility of excess demand functions 
Language:  English 
Keywords:  Uniqueness Equilibrium 
Subjects:  D  Microeconomics > D5  General Equilibrium and Disequilibrium D  Microeconomics > D5  General Equilibrium and Disequilibrium > D50  General D  Microeconomics > D5  General Equilibrium and Disequilibrium > D51  Exchange and Production Economies 
Item ID:  47300 
Depositing User:  Enrique Covarrubias 
Date Deposited:  01. Jun 2013 04:28 
Last Modified:  01. Jun 2013 04:46 
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URI:  https://mpra.ub.unimuenchen.de/id/eprint/47300 