How to Optimize the “Cost Exists but No Revenue” Dilemma in the Public Data Supply Chain—A Differential Game Analysis of Differentiated Subsidy Models
The authorization and operation of the public data supply chain is an important pathway for unlocking the value of public data and cultivating the data element market. However, in practice, it faces challenges such as insufficient data supply and insufficient stakeholder incentives. This paper focuses on the differentiated subsidy policies of the fiscal department, constructing a differential game model involving multiple participants, including data providers, data managers, and data operators. The paper systematically compares the optimal effort decisions of each stakeholder, the evolution trajectory of public data product value, and the trajectory of overall system profits under two subsidy models: cost subsidies and transaction subsidies. It further analyzes the regulatory role of revenue distribution ratios and cost-sharing contracts in shaping the effectiveness of these subsidy mechanisms. The study finds that: (1) cost subsidies provide more balanced and stable incentives for all stakeholders and contribute more to the final value trajectory of public data products; transaction subsidies are more effective in improving overall system profits but offer weaker incentives for the supply and management sides, requiring flexible use in conjunction with cost-sharing contracts; (2) cost-sharing contracts play a regulatory role under different subsidy models and effectively reduce the data provider’s dependence on fiscal subsidies under the transaction subsidy mechanism; (3) the revenue distribution ratio only positively affects the effort decisions of the supply and management sides under the transaction subsidy model, and the optimal subsidy ratio of the fiscal department is closely related to the revenue distribution ratio. Therefore, differentiated subsidy strategies should be implemented based on specific decision-making contexts and internal revenue distribution ratios. This paper reveals the synergistic incentive mechanism between differentiated subsidy models and cost-sharing contracts, providing a theoretical basis for the design of subsidy policies for public data authorization and operation.