【摘要】 本研究讨论一个富有挑战性的论题：由于在市场和政府交互作用的混合体制下农业和农村发展仍然存在效率缺失,那么,是否存在改进农业和农村发展效率以及农民福利的第三条道路?尽管长期以来经济学家对于何谓有限理性仍然没有一致性看法,但这一概念的引入仍然是完善经济学分析框架的重要途径。有限理性的个人决策有可能演化成具有社会理性的结局,有限理性的存在又是契约产生和契约不完全的重要因素,而契约理论所引申出的治理机制是寻找市场和政府之间的关于因有限理性、不确定性和信息问题导致市场失灵的解决方案。本文所探讨的第三条道路是基于有限理性和契约的农民集体行动,即通过合作实现帕累托效率。本文围绕“农业和农村发展中市场失灵与政府失灵并存——现有治理方案的不足——借助有限理性、契约与社会资本等工具性理论构建集体行动的分析框架——对农民经济合作、公共资源治理、公共物品供给和农村民主政治的集体行动进行理论拓展和实证检验——考察合作形式下的农业和农村发展效率改进与农民福利改善”这样一个主体思路展开研究。本文结合中国农村的改革前后的实践对市场失灵的市场治理、政府治理、契约理论等相关解决方案进行评价的基础上,借助有限理性、契约、集体行动与社会资本等工具性理论,构建一个农民合作的理论框架,探讨通过契约的方式能够在声誉博弈后阶段达成合作均衡,形成帕累托效率的农村集体行动——市场集体主义,即基于市场机制的农民合作能够走出市场失灵和政府失灵的双重困境。并通过拓展和应用这一理论框架对中国农民经济合作、农村公共资源治理、农村公共物品供给和农村民主政治等各方面进行解释和分析,利用各种宏观和微观数据以及相关案例检验理论研究的基本结论。并进一步探讨中国农村的各种合作是否能实现帕累托效率改进,以及如何改进现存的各种治理方案的不足。最后针对各种农业和农村发展问题提出相应的对策建议。本研究的结论和观点是：1.农业和农村发展中市场失灵与政府失灵体现了个人理性与集体理性冲突的囚徒困境。在有限次重复博弈中,不能改变囚徒困境的均衡结果。在无限次重复博弈中,农民将在长期的生产和生活中建立信任的基础,将会以一定的概率实现合作,走出囚徒困境。贝叶斯均衡、颤抖手均衡和序贯均衡都隐含了参与人信念一致性,信念的一致性决定了最终的均衡是否能够走去囚徒困境。契约能够强化信念的一致性,尤其是在参与人有限理性的情况下,契约仍然能够维持参与人信念的一致性,契约对农民在博弈过程中达成合作的集体行动具有关键作用。契约作为共同知识,能够克服有限理性,建立信任基础,促进均衡的进一步精炼,形成精炼贝叶斯均衡。不完全契约中,契约需要在修正信念的过程中不断完善,才能保证激励约束和参与约束的有效性。当参与农户由于有限理性和信息缺乏,无法通过贝叶斯法则得出后验概率的时候,契约是非均衡路径上形成信念一致性的关键因素。在有限理性农户的博弈过程中,当前一时期博弈不能达成合作的均衡结果时,具有声誉的引领型农户观察到其他类型农户的行动后,倡导通过契约的方式消除因有限理性、交易成本和信息不完全导致的不确定性,以契约保证农户的预期收益,这是达成农民之间合作集体行动的内生激励。2.中国农村改革前后农村经济合作的效率差别源于经济组织内部的委托代理关系激励效果的差异。改革后农民基于市场机制,自主加入经济合作组织对农民增收的具有显著正效应,是具有帕累托效率的集体行动。农民加入合作经济组织的行为除受预期利益的激励外,还受到农民个人素质特征和村庄特征的影响。契约下的经济合作能够有效规避有限理性农户决策的风险和对预期的不确定性,促进经济合作产生,实现帕累托效率。3.社会资本内含信任、规范和社会网络等基本范畴所形成的资本价值,其本质上是基于契约而产生的效率。在改进的KMRW声誉博弈模型框架下,个人理性能够在有限重复博弈阶段达成与集体理性一致——从冲突走向合作,即基于社会资本,以合作方式治理农村公共资源能够提高公共资源的利用效率。这说明产权私有不是解决“公共地悲剧”的唯一途径,这种简单化的产权效率方案在考虑资源配置效率的同时忽略了资源的初始禀赋对社会公平影响。4.基于契约博弈的农村公共物品供给方式能够弥补政府供给的效率问题和私人供给的不足问题。根据农户自身对公共物品的需求偏好,把具有相似需求结构的农户分群,在具有相似需求结构的群体内部自愿达成关于公共物品供给和成本分担的契约,契约基础上的公共物品供给博弈均衡,相对于政府供给和私人供给而言,是一个帕累托改进的博弈均衡。政府对公共物品的补贴行为,将强化帕累托有效的均衡结果。5.“投票悖论”是公共选择问题中一种固有的难题。阿罗不可能定理进一步证实了“程序民主”与“实质民主”的偏离。尽管阿马蒂亚·森以个人偏好排序和信息基础对阿罗不可能定理进行了乐观的解答。然而,在经济发展过程中,由于利益集存在,村民自治的集体行动会发生程序民主与实质民主相脱离。因此,需要通过契约完善民主程序,扩大村民的信息基础,稳定村民的偏好次序,防范小集团合谋。

　　【关键词】 有限理性； 契约； 集体行动； 农民合作； 社会资本；

　　【Abstract】 In this dissertation, I explore the question of whether exit a third road between market and government, which could improve the efficiency of agriculture and rural development, and farmers welfare? Despite not all economists remained consistent view of bounded rationality, it is also an important way to improve the framework for economic analysis. Individual decisions may evolve into an outcome of social rational based on bounded rationality, and the bounded rationality is the reason both of contract generating and incomplete. Contract theory and governance mechanisms are solution to market failure for bounded rationality, uncertainty and information problems. This paper discusses the third way is farmers’collective action based on bounded rationality and contract. This way could achieve Pareto efficiency through cooperation.Agriculture and rural development faces more serious uncertainty of nature environment and market than other economic activities. However, traditional theories and governance models to solute market failure and government failure are not entirely practiced in rural problems in China. So, I construct an analysis framework about rural cooperation base on instrumental theory consist of bounded rationality, contract, collective action and social capital. And then, this paper applied the theory to analyze issues including the rural economic cooperation, public resources in rural areas, rural public goods and rural politics. The conclusions and the views including:1. Agriculture and rural development with market failure and government failure reflects the prisoner’s dilemma of conflict between individual rationality and collective rationality. I find, in the finitely repeated game, the prisoner’s dilemma equilibrium can not be changed, and in infinitely repeated games, farmers will choice cooperation, and go out of the Prisoner’s Dilemma in a certain probability, because of trust in the long-term production and life. It is considered belief consistency of participant in Bayesian equilibrium, trembling hand equilibrium and sequential equilibrium. Aad belief consistency determines the final equilibrium. Contract can strengthen the consistency of beliefs, especially in the case of bounded rationality. Contracts are still able to maintain the consistency of participants in faith. Contract plays a critical role in reaching farmers’cooperative in the games. As a common knowledge, contract is able to overcome bounded rationality, establish a basis of trust and promote the balanced refining, and then produce perfect Bayesian equilibrium. In incomplete contract, the contract requires improvment in the process of faith amendment to ensure the effectiveness of the incentive constraint. When farmers due to the limited rationality and lack of information can not be obtained posterior probability through the Bayes rule, the contract is crucial basis of forming consistency faith in the non-equilibrium path. During the game, when bounded rationality farmers can not reach cooperation in the previous period, the lead-farmers with reputation will advocate eliminating uncertainty caused bounded rationality, transaction costs and incomplete information in way of contract after observing the actions of other types.This way will ensure the farmers expected return, also is the intrinsic motivation for cooperation.2. There are differences in the efficiency of rural economic cooperation before and after China’s rural reform, because of the incentive effects of the agency relationship within the organization. The behavior that farmers joined the economic cooperation organization based Market-mechanism has a significant positive effect of farmers’ income. So it is a collective action with Pareto efficiency. Farmer cooperative behavior is also subject to the quality characteristics of individual farmers and village characteristics. Economic cooperation under the contract can effectively avoid the risk of decision-making with limited rationality and uncertainty of expected income. And it also could promote economic cooperation, achieve Pareto efficiency.3. Social capital includes trust, norms and social networks, with the capital value of being formed by them. Its value is essentially generated based on the efficiency of contract. In the Improved KMRW reputation game, individual rationality can reach collective rationality in finite repeated games:from conflict to cooperation. It is to say that in a cooperative manner based on social capital to improve the governance of public resources in rural will be efficiency.4. The way of rural public goods supply through contract-based game could make up for the inefficiency of government supply and the shortage of private supply. According to farmers’own demand of public goods, households with similar demand structure will cluster. Then the group with similar demand structure will reach contract of public goods provision and cost-sharing. The game equilibrium based contract is a Pareto improvement game equilibrium, compared to the government supply and private supply. If the government subsidies public goods supply, the results will strengthen the equilibrium of Pareto efficient.5. "Voting Paradox" is an inherent problem in public choice. Arrow’s impossibility theorem confirmed the deviation of "procedural democracy"and "real democracy ". However, Sen give an optimistic answer for Arrow Impossibility Theorem through sorting personal preference and information base. In collective action of village self-government, democracy achieved level present the law of the first decreased and then increased with the economic development. Therefore, in order to improving the democratic process through the contract, we should expand the village’s information base, stable order of preference of the villagers to prevent small group collusion.

　　【Key words】 Bounded Rationality； Contract； Collective Action； Farmer Cooperative； Social Capital；