Surplus Allocation Mechanism in Vietnam's High-Speed Rail Public-Private Partnership: A Game Theoretic Approach

The development of high-speed rail (HSR) infrastructure in Vietnam is important for economic development, yet it demands substantial capital and risk management through public-private partnerships (PPPs). This study incorporates a comprehensive game-theoretic framework that integrates the multi-agent ultimatum game for initial bargaining under incomplete information, the Shapley value for fair cooperative surplus distribution and Nash bargaining for equitable refinements. Policy recommendations support increasing competition among private investors, institutional reform and adaptive contract mechanisms to achieve sustainable outcomes. This study will significantly contribute to the literature by reflecting non-cooperative and cooperative game theory in a real-world context and offering a robust tool for HSR PPP in Vietnam.