【摘要】 随着经济的发展和市场的完善,我国农业生产逐渐从生产导向型转变为市场导向型,农产品市场方式越来越依赖于产品特性、双方交易主体特征和交易特性,交易组织形式由市场交易逐渐向各种合同生产方式、纵向一体化等转变。而现有生产方式的改变、供应链垂直一体化和专业化程度的提高、国际食品市场开放度和价格竞争的加剧,都威胁着小农户的生存,这些挑战势必导致新的制度安排或组织形式的产生和发展。

　　目前,我国的农产品供应链结构和管理正处于转型和多种形式并存的局面,既有以小农户、贩销户、批发市场和加工企业等主体为代表的传统供应链模式,又有加入了农民合作社、超市、专业化配送中心和物流公司等为特征的新型供应链结构。作为代表小农户进入市场的农民合作社,能否真正为小农户带来经济效益?这正是本研究想要回答的问题。尽管关于这个问题的研究数不胜数,持肯定观点的占多数,却也不乏质疑的声音,但是现有研究大多为定性研究和案例研究,很少有深入、具有说服力的理论模型推导或数理模型检验。

　　本研究基于合作社影响农户的经济效益的假说,从三个角度来检验这一假说：第一,不存在合作社的市场和存在合作社的市场中,农户所获得的价格和收益是否不同?第二,合作社社员和非社员农户的生产效益是否有差异?第三,合作社社员和非社员农户的规模效率是否不同?

　　本研究的主要特点在于：首先,构建了博弈理论模型对农户选择交易组织形式的过程进行模拟和求解,这在国内尚属创新性和尝试性的研究；其次,实证研究中专注于一种特定的产品,即利用浙江省梨果产业的第一手数据,运用经典数理模型和计量工具对理论假说进行检验；再次,一方面理论模型的结论具有对所有地区和产品的普遍应用性和理论性意义,另一方面经验研究的结论具有对特定地区特定产业的实践性意义。

　　本研究的具体内容和结论如下：

　　第一章为绪论,交待本研究的现实背景和研究目的,提出本研究拟解决的问题,进而对本研究中的一些关键性概念进行界定,制定整个研究的技术路线图和内容框架,并介绍研究所使用的各种方法,最后提出本研究可能存在的创新和不足之处。

　　第二章为文献综述,梳理了各种合作社相关理论和农业生产效率及规模效率的成果,发现现有研究在关于合作社对农户生产效益及效率影响的理论模型研究和数量模型研究方面存在薄弱和空白,以此确定本研究的切入点。

　　第三章分别构建了在三种不同市场结构下小农户选择交易组织形式的博弈模型,即IOF垄断市场、IOF-合作社混合市场、纯合作社市场,求解博弈的均衡战略,模型结果显示,农户在IOF垄断市场中只能获得微薄的收益；合作社的出现提高了所有农户的收益水平；纯合作社市场虽然能够使农户收益达到最大,然而搭便车行为使资源分配极为不合理,因而并不是一个长期稳定的市场结构。

　　第四章介绍了浙江省农民合作社运行情况和梨果产业发展情况,解释以浙江省梨果产业为经验研究对象的理由,进而描述了样本抽取和数据收集过程,为开展第五章和第六章的计量分析奠定基础。

　　第五章为合作社对农户生产效益的影响研究,建立用以检验合作社是否影响农户的资金成本、自有劳动力成本、每亩产量、产品销售价格、每亩收益和净收益等生产效益指标的数理模型,检验结果显示,合作社社员的资金投入成本、产品价格、每亩收益和净收益都显著高于非社员农户,但是社员和非社员的自有劳动力成本和每亩产量并没有表现出显著性差异。

　　第六章为合作社对农户规模效率的影响研究,参照Battese & Coelli(1992)的经典前沿生产函数,结合柯布-道格拉斯生产函数,建立分组的随机前沿生产函数模型,将规模效率分解为面积规模效率、资金规模效率、自有劳动力规模效率,对社员和非社员两组农户的各个规模效率指标进行比较分析,模型结果表明,合作社提高了社员农户的总规模效率,同时对规模效率的结构产生了较为显著的影响；相对于非社员农户,社员的种植面积规模效率明显较高,但资金规模效率和自有劳动力规模效率较低；小规模和大规模社员农户的规模效率得到了较为显著的提高,但是这种效应没有对中等规模社员起作用。

　　第七章为本研究的结论和展望,对本研究做概括性的总结,提出一些政策含义,并展望今后可进一步研究的问题。

　　【关键词】 农民合作社； 生产效益； 规模效率； 博弈模型； 经验研究

　　【Abstract】 Nowadays as the economy developing and market perfecting, agriculture production is changing from production oriented to market oriented, agriculture product transactions depend more and more on characteristics of products, transaction participators, and transaction as well, and governance structure is transferring from market exchange toward contracting and vertical integration. The improving production methods, increased concentration in the supply chain, lower world prices and more open markets to international competition are all threatening to small farmers.

　　The product supply chain in China at present is diversified and undergoing transformation in both structure and management. It includes not only the traditional production-supply-marketing system constituting of small farm households, peddlers, processing enterprises, wholesalers, and retailers, but also new retailers such as farmer cooperatives, supermarkets, and specialized distribution centers. Therefore, is farmer cooperative, as a representative of small farmers, able to help farmers out and bring farmers economic benefits? That’s the question we are going to answer in our research. Although there are abundant studies on this issue, most of answers to which being positive, there are still skeptical voices. Besides, most of existing studies are qualititive studies and case studies, whereas seldom is devoted to theoretical model derivation or mathematical model examination.

　　This study examines the hypothesis that cooperatives have an influence on farmers’ economic benefits by answering three questions. Firstly, what are the prices and payoffs farmers obtain in a market without cooperatives and a market with cooperative respectively? Secondly, are there different production profits between cooperative members and non-member farmers? Thirdly, do cooperative members and non-member farmers differ in scale efficiencies in production?

　　There are some distinct characteristics in the study. (1) A theoretical model based on game theory is formulated to imitate and deduce enterprises’ pricing decision and farmers’ outlet choice in product marketing market. It is a creative and tentative research method applying to study farmer cooperatives in China. (2) The empirical study focuses on a specific product, i.e. pear in Zhejiang province, China. And classical mathematical models and econometric softwares are applied to examine the hypotheses. (3) The theoretical model comes to some conclusions with broad and general application, while the empirical analyses draw out some results which are of significantly practical meaning to specific area and industry.

　　Main contents and results of the studies are:

　　ChapterⅠis introduction. The research background, research objectives, and research questions are introduced, research technology roadmap and paper framework are formulated, and various research methods applied in the research are described. In addition, some innovation points and shortages of the research are concluded.

　　ChapterⅡis dedicated to literature review. Some theories related to farmer cooperatives, agriculture production efficiency, and scale efficiency are covered and sorted out. The research points are formulated when awaring that there are shortages and vacuum in quantitive studies pertaining to the impact of cooperatives on farmers’ production profits and efficiencies.

　　ChapterⅢformulates a game model of farmers’ choices for organizational forms in alternative market structures, i.e. pure IOF market, IOF-Coop mixed market, and pure cooperative market. According to the sub-game perfect equilibrium results, farmers gain a small profit in a pure IOF market; the presence of cooperatives in market increases farmers’ payoffs; although farmers gain the largest payoffs in a pure cooperative market, the free riding problem in a pure cooperative market leads to unreasonable or inefficient resource distribution.

　　ChapterⅣintroduces farmer cooperatives and pear industry development in Zhejiang province. Reasons for choosing pear industry in Zhejiang province as the population of emprical studies are explained. Then methods of sampling and data collection are elaborated. This chapter lays the foundation for emprical studies in the next two chapters.

　　ChapterⅤis devoted to the emprical study on the influence of cooperatives on farmers’ production profits. A statistical model is formulated to examine if cooperatives have an impact on members’ capital cost, family labor cost, yield per mu, product price, income per mu, and net income per mu in pear production. The results show that members have higher capital cost, product price, pear production incomeper mu, and net income per mu than non-members do. However, there is no significant difference in family labor investment or yield per mu between members and non-members.

　　Chapter VI examines the influence of cooperatives on members’ scale efficiency. Borrowing the classical frontier production function and Cobb-Douglas production function, a stochastic frontier production function model is established. By grouping farmers into members and non-members, scale efficiencies, including production area scale efficiency, capital scale efficiency, and family labor scale efficiency, are calculated and compared between the two groups. The results indicate that (1) cooperatives enhance the general scale efficiency of members; (2) members have a significantly higher production area scale efficiency than non-members, whereas non-members have higher capital scale efficiency and family labor scale efficiency; (3) cooperatives help to increase members with small production area and large production aear, rather than members with middle production area.

　　Finally, some conclusions, policy implications, and further researches in future are summed up in chapter VII.

　　【Key words】 Fanner cooperatives； production profits； scale efficiency； game theory model； emprical study