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 Gale-Nikaido 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 |
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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 Oct 2019 18:45 |

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URI: | https://mpra.ub.uni-muenchen.de/id/eprint/47300 |