中文摘要：

理性既可能诱发经济主体间的合作,也可能诱使交易各方选择不合作,二者的分界点在于交易成本的不同。本文发现,环境参数（地权约束、资本约束等）和交易维度（交易品自然属性、交易频率等）及其不同组合（和相互作用）将决定缔约各方选择集合的大小。给定环境参数,不确定性、交易频率、资产专用性、贸易（交易）半径、产品的自然属性等因素及其相关组合会直接影响交易性质并决定（潜在的）交易成本的大小,这意味着缔约双方或多方要通过缔结相应的合约来减少交易成本和降低经营风险。缔约各方对潜在交易成本和交易风险的不同反应会导致不同的缔约结构,有的缔约结构是有效率的,而有的缔约结构则缺乏效率。需要强调的是,理性诱导下的合作与不合作,都是在交易成本约束下的最优选择,都具备经济学意义上的合理性,但是,它们所蕴涵的经济绩效却截然不同。

英文摘要：

Rationality can not only induce cooperation among economic subjects, but also lead to non-cooperation, and the cut-off point is transaction cost. This article shows that environment parameters （e.g. constraints from land ownership and capital）, transaction dimensions （e.g. natural attributes of transaction goods and transaction frequency） and different combination possibilities of these two aspects will determine the size of selection sets of contracting parties. Given environment parameters, uncertainty, transaction frequency, asset specificity, trade radius, products＇ natural attributes and combination possibilities of them can directly affect the transaction characters and determine the size of potential transaction costs. That means economic subjects should conclude corresponding contracts to reduce transaction costs and cut down operational risks. Contracting parties＇ different reactions to transaction costs and risks bring about different contract structures. Some of contract structures are efficient; however, others may lack efficiency. The study emphasizes that both cooperation and non-cooperation which are induced by rationality are the optimal choices under the transaction cost constraints and that they both have economic implications. Nevertheless they have totally different economic performance.