产品创新如何影响企业加成率

How Does Product Innovation Affect Firm's Markup

本文从成本加成率角度分析企业获取创新垄断租金的微观机制,一方面,产品创新通过增加市场份额降低产品需求弹性,企业可以索要更高的加成率,即"市场份额效应";另一方面,产品创新带来的生产率提升促使企业边际成本降低,进而提升加成率,即"成本效应"。我们理论分析了"市场份额效应",并在成本加成率和生产率估计模型中考虑"成本效应",将企业创新纳入其生产率动态过程。利用2001-2007年中国工业企业数据研究验证了以下理论预期:产品创新通过增加市场份额显著提升了企业成本加成率,与此同时,产品创新也通过降低边际成本显著提升成本加成率,但"成本效应"弱于"市场份额效应"。考虑创新的自选择、测量误差和内生性问题后结论仍然稳健。

This paper analyzes how firms get monopoly rents from product innovation. Based on Atkeson and Burstein（ 2008）,we show that product innovation can help firms get more market share from its relative comparative advantage,which can lower its price elasticity and therefore charge higher markups. In addition,product innovation can help reducing the marginal cost and improving the price-cost margin. Using the 2001-2007 firm-level data in China,this paper provides evidence that product innovation can significantly improve firm＇s markup through both cost and market share channels. The results are robust even after considering the sample selection bias,measurement errors and endogenous problems.