混改背景下国有企业股权性质变化对企业创新效率的影响

党的十九大强调了“发展混合所有制经济”，国企混改将对企业创新效率产生一定的影响。为此，基于2009-2018年上市公司的财务数据和专利数据，运用双重差分模型和中介效应模型考察改制后国有企业的专利数量和质量的变化情况。结果表明：国有企业改制对企业的专利产出效率有积极作用，但是对企业的专利质量效率有消极作用，即国有企业改制会通过改变企业的融资约束和研发投入对企业的创新效率产生影响，融资约束和研发投入均对专利数量有遮掩作用，对专利质量有部分中介效用，改制后企业将更加重视企业经济目标，注重短期的专利数量成果，从而忽视创新专利的质量。

The Impact of Changes in the Nature of State-owned Enterprise Equity on Enterprise Innovation Efficiency under the Background of Mixed-ownership Reform

The 19th National Congress of the Communist Party of China emphasized the development of a mixed-ownership economy, and the mixed-ownership reform of state-owned enterprises will influence the innovation efficiency of enterprises. Based on the data of listed companies from 2009 to 2018, the double-difference model and the mediation effect model are used to examine the changes in the number and quality of patents of state-owned enterprises after the restructuring. The results show that the restructuring of state-owned enterprises has a positive effect on the efficiency of patent output, but a negative effect on the efficiency of patent quality. The mechanism test found that the restructuring of state-owned enterprises will affect the innovation efficiency of enterprises by changing the financing constraints and R&D investment of enterprises. Financing constraints and R&D investment have a masking effect on the number of patents and an intermediary effect on the quality of patents. Enterprises will pay more attention to economic goals and short-term quantitative results, and ignore the quality of innovation patents.