Journal of Applied Mathematics

  • J. Appl. Math.
  • Volume 2014, Special Issue (2013), Article ID 268427, 11 pages.

Existence of an Equilibrium for Lower Semicontinuous Information Acquisition Functions

Agnès Bialecki, Eléonore Haguet, and Gabriel Turinici

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We consider a two-period model in which a continuum of agents trade in a context of costly information acquisition and systematic heterogeneous expectations biases. Because of systematic biases agents are supposed not to learn from others' decisions. In a previous work under somehow strong technical assumptions a market equilibrium was proved to exist and the supply and demand functions were proved to be strictly monotonic with respect to the price. Here we extend these results under very weak technical assumptions. We also prove that the equilibrium price maximizes the trading volume and further additional properties (such as the antimonotonicity of the trading volume with respect to the marginal information price).

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J. Appl. Math., Volume 2014, Special Issue (2013), Article ID 268427, 11 pages.

First available in Project Euclid: 1 October 2014

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Bialecki, Agnès; Haguet, Eléonore; Turinici, Gabriel. Existence of an Equilibrium for Lower Semicontinuous Information Acquisition Functions. J. Appl. Math. 2014, Special Issue (2013), Article ID 268427, 11 pages. doi:10.1155/2014/268427.

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