Existence of Competitive Equilibria without Standard Boundary Behavior

Francesco Ruscitti

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DOI: 10.4236/am.2011.211198                

Abstract

We study the existence of competitive equilibria when the excess demand function fails to satisfy the standard boundary behavior. We introduce alternative boundary conditions and we examine their role in proving the existence of strictly positive solutions to a system of non-linear equations (competitive equilibium prices). In addition, we slightly generalize a well-known theorem on the existence of maximal elements, and we unveil the link between the hypothesis of our theorem and one of the boundary conditions introduced in this work.

Keywords

Excess Demand Function, Competitive Equilibrium, Set-Valued Functions, Selections, Fixed Points, Maximal Elements

Conflicts of Interest

The authors declare no conflicts of interest.

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