The purpose of this study is to discuss the phenomenon of dual-role participants in public-private partnership (PPP) projects. Contractors who are also investors hold a dual-role that can improve project financing and technical ability. However, speculation without effort from the dual-role subjects can result in serious conflicts of interest between pure and dual-role investors. The authors considered contractors’ decisions regarding whether to invest and exert effort and discussed the distribution of interests between pure and dual-role investors based on different strategy combinations. The authors also analyzed the advantages and disadvantages of the dual-role phenomenon through the income model.,Based on game theory, this study constructed four types of revenue structure models for pure and dual-role investors in different decision-making choices. Then, the authors performed a comparative analysis of the dual-role participant’s income in different models.,When the contractor becomes a dual-role subject and expends significant effort (m1*), the revenue of stakeholders can be increased, which can achieve a win-win outcome. Meanwhile, the level of effort of the contractor can be guaranteed when the government or project company limits the investment proportion, rj. For a contractor, the channel of becoming a dual-role subject and expending effort is suggested for maximizing investment return.,The study optimized the PPP project system and investment structure and offered specific governance instruments for a PPP project company to prevent speculation by dual-role subject. Concretely, a dual-role subject was discussed in the context of PPPs; this discussion offers new insight for researchers. Four revenue models based on different contractor strategies were established, a finding that is beneficial for further improving the revenue governance of PPP projects. Finally, the study used a quantitative model to validate the advantages of the dual-role phenomenon, and the authors found that the proportion of equity can impact a dual-role investor’s effort level, thereby curbing speculation to produce a win-win outcome.

中文翻译：

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PPP项目中作为投资人的双重角色的收入结构

本研究的目的是讨论公私伙伴关系（PPP）项目中双重角色参与者的现象。既是投资者又是承包商的双重角色可以提高项目融资和技术能力。但是，双重角色主体的投机活动可能会导致纯角色和双重角色投资者之间的严重利益冲突。作者考虑了承包商关于是否进行投资和努力的决定，并讨论了基于不同策略组合的纯角色和双重角色投资者之间的利益分配。作者还通过收入模型分析了双重角色现象的利弊。，基于博弈论，本研究为处于不同决策选择的纯角色和双角色投资者构建了四种类型的收入结构模型。然后，作者对不同角色的双重角色参与者的收入进行了比较分析。当承包商成为双重角色主体并花费大量精力（m1 *）时，可以增加利益相关者的收入，从而实现双赢的结果。同时，当政府或项目公司限制投资比例rj时，可以保证承包商的努力水平。对于承包商而言，建议将其变成双重角色和付出努力的渠道，以使投资回报最大化。该研究优化了PPP项目系统和投资结构，并为PPP项目公司提供了特定的治理手段，以防止双重角色投机。具体而言，在PPP的背景下讨论了双重角色的主题。这次讨论为研究人员提供了新的见识。建立了基于不同承包商策略的四种收入模型，这一发现有助于进一步改善PPP项目的收入治理。最后，该研究使用定量模型验证了双重角色现象的优势，作者发现，股权比例可以影响双重角色投资者的努力水平，从而抑制了投机以产生双赢的结果。这次讨论为研究人员提供了新的见识。建立了基于不同承包商策略的四种收入模型，这一发现有助于进一步改善PPP项目的收入治理。最后，该研究使用定量模型验证了双重角色现象的优势，作者发现，股权比例可以影响双重角色投资者的努力水平，从而抑制了投机以产生双赢的结果。这次讨论为研究人员提供了新的见识。建立了基于不同承包商策略的四种收入模型，这一发现有助于进一步改善PPP项目的收入治理。最后，该研究使用定量模型验证了双重角色现象的优势，作者发现，股权比例可以影响双重角色投资者的努力水平，从而抑制了投机以产生双赢的结果。