Study on the decision of PPP project return mechanism under the public value perspective: based on PSO-TRP model

The return mechanism is the core attribute of Public-Private Partnership (PPP) projects, and the government is the key decision-making body of the cooperative production of public services in PPP projects. The decision-making logic of its return mechanism is related to the balance between the public nature of the PPP project and the economic efficiency, which is the key issue that directly affects the success or failure of the PPP project. First, the research hypotheses were proposed by comprehensively considering the public nature of PPP projects, the reference point effect, and the law of diminishing marginal utility. Second, the tri-reference point theory (TRP) was introduced to construct a decision model of the PPP project return mechanism and analyze its constraints. Finally, the particle swarm algorithm was used to conduct case simulation, scenario simulation, and option selection for the decision-making problem of the government, aiming at how to choose the payoff mechanism in order to maximize the utility in the context of budget constraints and bottom line logic. The study found that: 1) the government ’ s perceived value in PPP projects increases and then decreases as the goal rises, showing an inverted U-shaped distribution, with the perceived value and effort level increasing with the bottom line, and the optimal position is that the public value is maximized. 2) When the government ’ s bottom line is certain and the target is high, the government fully or partially cedes public resources to the social capital body, choosing the user-payment or feasibility gap subsidy mode. 3) When the value of the government ’ s psychological weight changes, the greater the weight of success, the subject in the optimal range of objectives increases the degree of their inputs, and chooses risky behavior based on public value; when the greater the weight of failure, the subject of the decision-making process would reduce the degree of their input, and choose to protect the bottom of the behavior based on public value. Based on the public value perspective and the introduction of the tri-reference point theory, the study constructed a decision-making model for the return mechanism of PPP projects based on particle swarm algorithm, which provides a new idea for the research of governmental decision-making in PPP projects, and at the same time provides a reference for the maintenance of the public nature of PPP projects and the realization of public value. © 2024, Central South University Press. All rights reserved.