Study On Risk Sharing For PPP Projects Based On Game Theory

In recent years,with the rapid economic and social development of our country,the urbanization has accelerated and the country's demand for infrastructure has increased dramatically.Social capital gradually participates in China's infrastructure construction,and more and more projects use the public-private partnership model(PPP model)for construction.By the end of 2017,there have been a total of 13,554 national warehouse projects with a total investment of 16.4 trillion yuan.Although there are many PPP projects,there are not many successful implementations because of many reasons.The most important one is the sharing of project risks.The current research on the risk sharing of PPP projects is not deep enough,especially on the issue of shared risk sharing,and there is no effective sharing scheme.Each party in the PPP project uses its own advantages and tries to push the risk to the other party.When the other party can't afford it,the project cannot be implemented.This article starts with solving this contradiction point and proposes the risk of a reasonable sharing of the project,so that the participants can achieve the goal of cooperation and win-win.The study of this paper is based on the construction of a game-based risk sharing model for PPP projects.Specifically,it is based on the static game for the initial classification of risks,dividing out the burdens and sharing the risks;based on the cooperative game,the proportion of risk sharing is shared,and the distribution ratio of the shared risks is solved.This model has important theoretical and practical significance for the successful implementation of PPP projects.This article reviews the basic theories of project risk and risk management.The basic characteristics of the subjects and objects of the PPP project risk sharing are described.The main influencing factors of project subject risk sharing are clarified,and the game characteristics of the risk sharing subjects and the randomness and relativity of the risk sharing objects are analyzed.Based on the RBS risk structure decomposition and the identification of key risks based on the existing literature data,a rough risk list was identified.Then,the identified risk list was sorted out and classified,and the risk list needed to be studied was obtained.Based on the static game theory,according to whether there is a unique Nash equilibrium solution,the risk of a PPP project can be divided into a single risk and a shared risk.For the sole risk,after the project risks occur,the relevant risk bearers independently control the risks.The focus of the study is to share risks,build a shared risk sharing model based on the Shapley value theory in cooperative game theory,and find the risk balance points between game subjects to determine the proportion of government and social capital that need to bear risks.Make it easy for all parties to participate.To achieve a win-win situation.Shapley's value theory is based on the contribution of each project participant's contribution to cooperative alliances.It first calculates the initial share of risk sharing,and then considers each party's return and risk symmetry,willingness to take risks,and risks.The factors such as whether the capacity is up to the upper limit are adjusted,and the initial Shapley value is adjusted to obtain the final proportion of risk sharing.Finally,based on the PPP project of sewage treatment plant started in C City,this paper validates the risk sharing model of PPP project based on the game theory proposed in this paper and achieves good results.This paper proposes a PPP project risk sharing model based on the static-cooperative game theory,which makes up for the lack of research on existing PPP project risk sharing and provides a basis and new ideas for the reasonable sharing of risk among PPP participants.The beneficial exploration and supplement of PPP project risk sharing theory.