1、摘 要伴随着中央政府在根底设施领域大力推行PPP模式，2023年以来我国的根底设施PPP建设工程出现了爆发式增长。政府通过将社会资本引入根底设施工程建设，不仅可以减轻自身的财政压力，还能有效利用社会资本提升工程建设效率，因此，公私合作呈现出较广阔的开展前景。然而，随着实践的推进，在PPP工程参与方合作过程中，由于社会资本的天生逐利性，会引发一系列逆向选择和道德风险问题，这些问题已经严重阻碍了PPP工程的顺利推进。因此，如何有效地鼓励和监督社会资本已经成为确保PPP工程顺利推进的重要环节。本研究首先对PPP模式相关理论、政府监管理论、鼓励规制理论、委托代理理论等做了系统的阐述，强调了政府监管和鼓
2、励的重要性。其次分析了我国根底设施PPP工程的政府监管与鼓励现状，提出了目前的监管模式和鼓励手段存在的问题，并尝试从两个方面解决政府对社会资本的鼓励和监督问题，即先确定鼓励和监督的最优力度，再选择最正确的鼓励方式自己能起到作用的监督管理机制。第一局部是根据委托代理的经典理论来阐述的，引入政府对社会资本的鼓励与惩罚函数，基于参与约束与鼓励相容原理建立了政府期望收益最大化的委托代理模型，求解了公私双方在不同风险态度下政府的最优监督力度和鼓励水平，以及社会资本的最优努力水平，设计了一个包含政府鼓励和监督的最优鼓励监督契约。通过求解模型得出：在根底设施PPP工程中，政府与社会资本不同的风险态度会对公私
3、双方期望收益产生影响。政府鼓励与监督是有效的，社会资本努力水平与政府鼓励水平和监督力度均呈正相关；政府可以通过鼓励和监督引导社会资本采取更高努力水平；当政府为风险躲避时，政府愿意通过提供更高的鼓励水平来促使社会资本努力工作；而当社会资本为风险躲避时，政府将降低鼓励水平减少社会资本的收益分成。政府监督力度存在一个最优值，能更好地促使社会资本努力工作。第二局部通过实证分析的方式对委托代理视角下政府鼓励社会资本的16种鼓励措施进行分类和排序，并分析何种鼓励措施能更好地促使社会资本努力工作，同时建立了政府监管机制，实现更好的监管。得到的相关结论如下：政府对社会资本鼓励的一级鼓励指标中，鼓励效果较好的是
4、工程的经济支持和相关政策法规支持，工程相关的资本增值保证鼓励效果较差。其中，政府对工程的经济支持5种具体鼓励措施，鼓励效果最好的是税收减免，贷款贴息、融资协助和财政补贴鼓励效果居中，投资赞助的鼓励效果最差；政府对工程的政策法规支持6种具体鼓励措施，鼓励效果最好的是政策完备与连续稳定和工程审批流程通畅，招投标过程标准与公正、工程退出机制健全和工程纠纷协调通道顺畅鼓励效果居中，工程信息公开透明的鼓励效果最差；政府对工程相关的资本增值保证5种鼓励措施，鼓励效果最好的是工程效劳定价调整，特许经营期、工程沿线开发权、工程相关配套设施保证鼓励效果居中，工程唯一性保证的鼓励效果最差。建立PPP工程监管体系，
5、提出设立独立的综合性监管机构，以实现更好的监管。最后以某市的群众创业园工程建设为背景,根据本文研究结论针对该工程建立了良好的鼓励机制和监督机制，分析了政府鼓励和监督的有效性，验证了合理的鼓励和监督机制对提升根底设施PPP工程实施效果的重要性。关键词：委托代理；PPP工程；鼓励；监督；风险态度；AbstractSince 2023, as the central government has vigorously promoted the PPP mode, Chinas PPP project has reached a climax. By introducing social capita
6、l to participate in the construction of public projects, the government financial pressure has been alleviated and on the one hand, the efficiency of social capital has been fully made use of. Public-private partnerships have broad prospects. However, in the process of cooperation, as social capital
7、 is inherently profit-oriented, it can lead to a series of adverse selection and moral hazard problems with the advance of practice, which seriously hinder the construction process of PPP projects. Therefore, effective stimulation and supervision of social capital plays an important role in promotin
8、g the success of PPP projects.In this study, we first expounded the theory of PPP, government regulation theory, incentive regulation theory, the principal-agent theory, and emphasized the importance of government regulation and incentive. Secondly, analyzed the current situation of government super
9、vision and incentive of infrastructure PPP projects in China, and puts forward the existing problems in the supervision mode and incentive mechanism, then proposed to solve the problem of governments incentive and supervision on social capital from two aspects, one is to determine the optimal streng
10、th of incentive and supervision, the other is to choose the best incentive method and reconstruct the supervision system.In the first part of this paper, based on the principal-agent theory, we have introduced the governments incentive and penalty function for private investors, established a princi
11、pal-agent model maximizing the expected income of the government based on the participation constraint and incentive compatibility principle, solved the governments optimal supervision and incentive levels, and the optimal effort level of private investors under different risk attitude of both parti
12、es, finally designed a optimal incentive supervision contract for the government. By solving the model, it is concluded that: In the infrastructure PPP project, the different risk attitudes of the government and private investors will have an impact on the expected earnings of each. Government incen
13、tives and supervision are effective, and the level of private investors efforts is positively correlated with the level of government incentive and supervision. The government can encourage and supervise private investors to take higher efforts. When the government is risk-averse, the government is
14、willing to encourage private investors to work hard by offering higher incentives. When private investors are risk-averse, the government reduces incentives to reduce the share of private investors profits. There is an optimal level of government oversight that would better encourage private investo
15、rs to work harder.In the second part of this paper, 16 kinds of incentives are classified and sorted from the perspective of principal-agent to analyze what can better encourage social capital to work hard through the empirical analysis, and a regulatory mechanism has been established at the same ti
16、me to achieve better regulation. The relevant conclusions are as follows: In the first level of incentive indicators , economic support and related policies and regulations support have better incentive effect, project-related capital appreciation guarantee has poorer incentive effect. Among the 5 kinds of specific incentives of economic support, tax credit is the best , discount loans , financing assistance and financial subsidy are the second, investment sponsor is