Study On Concession Period Decision-making Of PPP Project Based On Government Guarantee Option And Game

With the development of economy and society,the demand for public infrastructure is also increasing while the government financing could not satisfy the needs of the society.Therefore,the PPP financing model emerges as the times requires and has been widely used in the field of infrastructure construction.PPP financing model can not only solve the problem of government lack of funds,but also can attract privat.e capital to get involved in the field of infrastructure,improving the use efficiency of the fundsThe concession period is an important reference in the PPP project financing,and its reasonable determination is the key to the success of the project.However,so far,the determination of the concession period of PPP project is still a very difficult problem,and the determination method is not satisfactory.Starting from the determination of the concession period of the PPP project,the paper analyzed the factors which influence the concession period of PPP project and the impact of the government guarantee on the concession period.Then it constructed the concession decision model of PPP project under the government guarantee,and combining with cooperative game theory,established the game model on the concession period between the government and the private investors.Firstly,the paper summarized the factors influencing the concession period by literature analysis and classified them.Through the analysis of the option characteristics of the government guarantee and combining with the real option theory,the pricing model of the government guarantee option was established.Then,according to the interests of the parties,it constructed the comprehensive decision model of PPP project under the government guarantee from the perspective of the government and the private investors on the basis of the traditional concession decision model,and used Monte Carlo method to solve the scope of the concession period.For the scope of the concession period,the paper constructed the cooperative game model between the government and the private investors after dimensionless processing,and solved the Nash equilibrium solution according to the Nash solution method.At last,combined with the practical case of PPP project,the traditional concession period decision model and the model constructed by this paper were used to calculate the concession period,the comparions about which were made to verify the validity and rationality of the model which was established in the paper.This paper used the real option and cooperative game theory to further study the problem of the concession period of PPP project and compared the results with the decision results of the traditional concession deicision model.It is found that the model constructed in this paper can reflect the interests better of the government and the private investors and the concession period is closer to reality,which provides a theoretical reference for the government to make decision on the concession period of PPP project in the future.