Grey Clustering Evaluation for the Cooperation Efficiency of PPP Project: Taking Beijing Metro Line 4 as an Example

Table 1

PPP project cooperation efficiency index system.

Categories	Factors	Indexes	Definitions	Resources
Government	Satisfy Public Requirement	X1 Reliable quality	High quality of public product/service	Clarkson [47]; Li et al. [48]
		X2 Satisfied public product/service requirement	The new-built, renovated, and expanded public facilities need to satisfy the requirement of economic and social development	Bryson [18]
		X3 Safety construction and operation	Avoid safety accident during the construction and operation process of the project	Li et al. [32]; Shi et al. [23]
		X4 Reasonable pricing system	Define the price standards and adjust procedure based on the project investment and operational cost, and then control the services change of the franchise company	Zhan et al. [8]; Verweij [31]
	Avoid Renegotiation	X5 Avoid concession period extension	Avoid the renegotiation to extent concession period	Tiong [9]; Yang et al. [19]
		X6 Avoid increasing financial responsibility during concession period	Avoid the renegotiation to increase the financial expenditure	Tiong [9]; Osei-Kyei and Chan [49]
		X7Avoid price increase during concession period	Avoid private sector increasing the price through renegotiation and then increasing the burden of the users	Yang and Zou [19]; Thomas et al. [50]
	Promote Urban Development	X8 Environmentally sustainable development	Sustainable utilization of resource and energy, sustainable maintenance of the ecosystem	Yang and Zou [19]; Villalba-Romero and Liyanage [28];
		X9 Promote regional economic development	Create job opportunities, increase local regional investment capacity, accelerate local economic development, guiding and radiation effects for the regional economic increase	Villalba-Romero and Liyanage [28]; Xiong et al. [30]
		X10 Improve the construction and operation efficiency of the public project	Introduce the advanced technology and management capacity of private sector, provide high quality public product/services with low cost	Li et al. [48]; Verweij [31]
	Successfully Develop Works	X11 Complete the project in time	Complete the construction of PPP project in time	Ng and Loosemor [21]; Rugters and Haley [22]
		X12 Transfer part of risks	Transfer part of the risks to private sector	Rugters and Haley [22]; Humpherys et al. [23]
		X13 Good condition of facilities after transfer	PPP project maintains good facility conditions after transfer	EI-Gohary et al. [24]; Yuan et al. [29]
	Reduce Financial Pressure	X14 Avoid high supervise cost	Due to the involvement of private capital, private sector owns some control for the project; it is difficult for government to supervise and the supervise cost will also increase	Liu et al. [27]; Villalba-Romero and Liyanage [28];
		X15 Reduce financial pressure	Reduce the financial pressure of the government to provide public product/service	Yuan et al. [29]; Maskin and Tirole [35]
Private Sector	Project Profit	Y1 Low Cost	Reduce project cost	Xiong et al. [30]
		Y2 Satisfy return on investment	The operation of the project can meet the requirement of return on investment	Li et al. [48]; Mladenovic et al. [26]
		Y3 Reasonable pricing principle	Stable income in long term and avoid the reduction of charge price	Yuan et al. [29]; Xiong et al. [30]
		Y4 Reasonable concession period	Reasonable concession period can guarantee the return of the project	EI-Gohary et al. [24]; Xiong et al. [30]
		Y5 Many users	The project can attract many users	Grimsey and Lewis [36]; Klijn and Koppenjan [38]
	Government Support	Y6 Avoid project overspend	Avoid the project investment exceeding the planned investment	Xiong et al. [30]
		Y7 Avoid unreasonable intervention from the government	Avoid the illegal property requirement from the government through illegal influence, and result in costing increase in maintaining relationship.	Ismail [34]; Maskin and Tirole [35]
		Y8 Gain the policy support from the government sector	Own the guaranteed benefits, tax incentives, bundled development, logistics, and so on	Warsen et al. [39]; Leitch and Motion [40]
	Project Construction	Y9 Safe construction and operation	Avoid safety accident during the construction and operation process of the project	Li et al. [48]; Liu et al. [51]
		Y10 Standard quality	The quality of public product/service meets the expected standard	Lebas [25]; Mladenovic et al. [26]
		Y11 Complete the project in time	Complete the construction of PPP project in time	Tiong [9]; Paletto et al. [20]
	Public Relationship	Y12 Establish long-term cooperation relationship with the government	Establish good long-term cooperation relationship, increase mutual trust and the future cooperation opportunities, and also make the cooperation more successful.	Tiong [9]; Osei-Kyei and Chan [49]
		Y13 Improve the reputation and credibility of enterprise	Establish good social image, raise reputation, and achieve social responsibility of enterprise	Xiong et al. [30]
Public	Operational Reliability	Z1 Reliable construction quality	High level of public product/service quality	Villalba-Romero and Liyanage [28]; Yuan et al. [29]
		Z2 Good environment	Good and comfortable environment for public products	EI-Gohary et al. [24]
		Z3 Good operational function	Strong operational functions of public product, which can meet the client’s requirements	Yuan et al. [29]
		Z4 Timely convenient service	Service in time, improve the convenience of the users	Mladenovic et al. [26]; Liu et al. [27]
		Z5 Safety operation	Safe services, low occurrence of malfunction	Mladenovic et al. [26]
	Operational Price	Z6 Low price	Low operational price	EI-Gohary et al. [24]
		Z7 User subsidy from the government	Avoid the decrease of the user subsidy standard from the government to private sector and resulting in the decrease of the public product or service quality provided from private sector	Maskin and Tirole [35]; Zhang et al. [37]
		Z8 Reasonable compensation	Fair and reasonable compensation for public during the process of land requisition and demolishment	Liu et al. [51]