In this work, we study the Berge equilibrium problem (BEP) using a variational inequality (Ⅵ) framework. We establish an exact equivalence between the classical BEP and a corresponding Ⅵ problem under a pairwise symmetry condition. Furthermore, we extend this framework to generalized Berge equilibrium problems with shared (jointly convex) constraints, proving that the proposed Ⅵ formulation provides a rigorous sufficient condition for generalized Berge equilibria under appropriate assumptions. Illustrative examples are presented to demonstrate the theoretical findings.
Citation: Mengkezhula Sagaarenchen, Battur Gompil, Batbileg Sukhee, Ankhbayar Gelegbadam, Enkhbat Rentsen. A variational inequality approach to Berge equilibrium problems[J]. Journal of Industrial and Management Optimization, 2026, 22(12): 6150-6165. doi: 10.3934/jimo.2026207
In this work, we study the Berge equilibrium problem (BEP) using a variational inequality (Ⅵ) framework. We establish an exact equivalence between the classical BEP and a corresponding Ⅵ problem under a pairwise symmetry condition. Furthermore, we extend this framework to generalized Berge equilibrium problems with shared (jointly convex) constraints, proving that the proposed Ⅵ formulation provides a rigorous sufficient condition for generalized Berge equilibria under appropriate assumptions. Illustrative examples are presented to demonstrate the theoretical findings.
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