Non-Separable, Quasiconcave Utilities are Easy -- in a Perfect Price Discrimination Market Model

Vijay V. Vazirani

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arXiv · 1010.4281

Non-Separable, Quasiconcave Utilities are Easy -- in a Perfect Price Discrimination Market Model

Vijay V. Vazirani

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Abstract

Recent results, establishing evidence of intractability for such restrictive utility functions as additively separable, piecewise-linear and concave, under both Fisher and Arrow-Debreu market models, have prompted the question of whether we have failed to capture some essential elements of real markets, which seem to do a good job of finding prices that maintain parity between supply and demand. The main point of this paper is to show that even non-separable, quasiconcave utility functions can be handled efficiently in a suitably chosen, though natural, realistic and useful, market model; our model allows for perfect price discrimination. Our model supports unique equilibrium prices and, for the restriction to concave utilities, satisfies both welfare theorems.

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BibTeX RIS

Vijay V. Vazirani. 2010-10-20. Non-Separable, Quasiconcave Utilities are Easy -- in a Perfect Price Discrimination Market Model. https://arxiv.org/abs/1010.4281

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