中文摘要：

在混合所有制改革背景下，对不同改革方案下企业的产权结构及市场运行结果进行研究，可以提高政策设计的精准性。本文分析了非国有产权企业进入原本由混合所有制企业控制的市场以及混合所有制企业参与交叉持股等情形下的结果。研究发现，如果非国有产权企业是市场中的新进入企业，将导致混合所有制企业中的最优国有产权比重下降；但如果非国有产权企业由原在位混合所有制企业转换而来，那么，只有当产品差异化程度较高时，混合所有制企业中最优的国有产权比重才会下降。本文将混合所有制企业参与的交叉持股区分为：混合所有制企业间交叉持股的“宝武方案”、1个混合所有制企业与1个非国有产权企业间交叉持股的“国药方案”，以及1个混合所有制企业与多个非国有产权企业间非对称交叉持股的“中建方案”。结果显示，中建方案下混合所有制企业中的最优国有产权比重总是低于国药方案；当产品间差异化程度较大时，宝武方案下混合所有制企业中的最优国有产权比重在三种方案中最低，而当产品间差异化程度较小时，宝武方案在三种方案中最高。在政策定位上，宝武方案、国药方案及中建方案的改革目标应分别为增强混合所有制企业的市场控制力、市场竞争力以及市场领导力。

英文摘要：

In the context of mixed ownership reform, the research on the property right structure and market operation results of different reform schemes can improve the accuracy of the policy design. This paper analyzes the results of the non-state owned enterprises entering into the market controlled by the mixed ownership enterprises and the mixed ownership enterprises participating in the cross shareholding. The research finds that if the non- state-owned enterprise is a new enterprise entering the market, the optimal state-owned property rights proportion in the mixed ownership enterprises will decline, but if the non-state-owned enterprise is transformed from an original mixed ownership enterprise, only when the degree of product differentiation is high, the optimal state- owned property rights proportion in the mixed ownership enterprises will decline. In this paper, the cross ownership of mixed ownership enterprises is divided into three types ：cross shareholding presents mixed ownership enterprises （Baowu Scheme）,a mixed ownership enterprise and a non-state-owned enterprise （Guoyao Scheme）, and a mixed ownership enterprise and multiple non-state-owned enterprises （Zhongjian Scheme）. Results show that the optimal state-owned property rights proportion in mixed ownership enterprises under Zhongjian Scheme is always lower than the result under Guoyao Scheme. When the degree of product differentiation is high, the result under Baown Scheme is the lowest in the three modes, when the degree of product differentiation is low, the result under Baowu Scheme is the highest. And the policy objective of Baowu, Guoyao and Zhongjian Scheme respectively correspond to enhance the market control ability, market competitiveness, and market leadership of the mixed ownership enterprises.