Abstract
We propose a normal subgradient projection algorithm for approximating a solution of equilibrium problems involving quasiconvex para-pseudomonotone bifunctions, which is also a fixed point of an asymptotically nonexpansive mapping. The proposed algorithm is a combination between a projection one for the equilibrium problem and the Ishikawa iteration scheme for the fixed point. Convergence of the algorithm is proved without any Lipschitz type condition for the bifunction. Applications to a modified Walras equilibrium model with implicit supply and demand are discussed.
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Acknowledgements
The authors would like to thank the editor in chief, the editors and the referees very much for their constructive comments and suggestions, especially on the sufficient condition for the existence of a common solution of equilibrium and fixed point problems and the presentation of their submitted version. These helped them very much in revising their paper.
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A part of this article was written while the third author was visiting Vietnam Institute for Advanced Study in Mathematics (VIASM). He would like to thank the institute for warm hospitality and partial support.
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Hai, N.N., Muu, L.D. & Van Dinh, B. An algorithm for quasiconvex equilibrium problems and asymptotically nonexpansive mappings: application to a Walras model with implicit supply–demand. Math Meth Oper Res 98, 299–324 (2023). https://doi.org/10.1007/s00186-023-00837-w
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DOI: https://doi.org/10.1007/s00186-023-00837-w