中文摘要：

本文在Antweiler研究框架的基础上,结合不完全契约理论,构建了企业排污的一般模型,并使用＂差异中差异＂的估计方法,基于省级制造业大类行业数据,考察契约制度对环境质量的影响。研究发现,地区契约制度是影响环境质量的重要因素,在契约制度较为完善的地区,企业倾向于投入＂减排专用资本＂进行污染减排活动,进而改善环境质量。但是这种积极作用在契约密集度较高的行业并没有得到进一步强化,而行业本身的污染强度属性则可以解释这一＂反常＂的结果。为克服内生性问题,采用工具变量法进行再估计,上述结论依然稳健。

英文摘要：

Based on the research of Antweiler and combining the incomplete contract theory,this paper develops a general model of pollution discharge, and then uses the Difference-in-Difference method with data of two-digit manufacturing industries of China to examine the impact of the contract institution on the environmental quality. The empirical result shows that contract institution is the key factor of pollution discharge. Moreover,firms are apt to invest special emission reduction capital to reduce pollution and improve environment quality in the region where contract institution is comparatively complete. However,this positive effect fails to be strengthened in higher contract intensive industries. The abnormal result can be explained by pollution intensity of the industry itself. The previous result is still stable after controlling a series of factors such as per capita capital,human resources,foreign direct investment and external trade.