Digital empowerment, subsidy coordination, and food security: a tripartite evolutionary game with simulation analysis

Against the backdrop of the deep integration of digital technology and agriculture and the coordinated advancement of the national food security strategy, the effectiveness of digital technology in enhancing food security increasingly hinges on the interaction and coordination among local governments, digital agriculture service providers, and grain producers. This paper constructs a three-party evolutionary game model that incorporates key variables, including the digital empowerment coefficient, the technology accessibility coefficient, differentiated subsidy parameters, and central government incentives. It systematically analyzes the evolutionary trajectories of the three parties' strategies and the conditions for steady-state transitions under various parameter combinations. Furthermore, it conducts numerical simulations using benchmark parameters calibrated through multi-source data fusion. The research reveals four typical evolutionary scenarios. First, when the technology is effective and the service is profitable, the system converges toward an ideal steady state of tripartite collaboration. Second, when the technology is effective but the service is less profitable, the steady state hinges on whether subsidies can offset cost disadvantages and on the strength of government incentives. Third, when there is sufficient momentum on the service side, but the technology lacks appeal, the core bottleneck lies in stimulating key stakeholders' willingness to adopt it. Finally, when both technological effectiveness and market profitability are weak, the system risks becoming locked into a low-level equilibrium. Benchmark parameter calculations indicate that China's major grain-producing regions currently exhibit the characteristic of being "technologically effective but with weak profitability among service providers," and that the system possesses an intrinsic drive to converge toward an ideal steady state. Sensitivity analysis reveals four key levers driving the system's evolution: the digital empowerment coefficient, the intensity of subsidies targeting primary actors (grain producers), service providers' operating costs, and the scale of central government incentives. Therefore, policy design should shift from a single-instrument reliance to a differentiated and coordinated approach, tailoring implementation strategies to the specific stage of regional development. A portfolio of policy instruments, centered on these key parameters, should be developed to integrate demand-side incentives, supply-side support, and government performance assessments. Furthermore, facilitating the cross-regional transfer of theoretical models and policy experience can provide a sustainable driver for leveraging digital technologies to enhance food security.