进口竞争、产品差异化与企业产品出口加成率

Import Competition,Product Differentiation and Firm-Product Markup in Export Market

本文借鉴De Loecker等(2016)的方法,测度了企业-产品层面的生产要素投入,度量了我国企业产品出口加成率,并区分产品差异化程度,实证研究产品层面关税降低导致的进口竞争对于企业产品出口加成率的影响。总体上,进口竞争显著提升了企业产品出口加成率,区分产品差异化程度后,发现其对异质性产品出口加成率有显著促进效应,而对同质性产品出口加成率的影响效应不明显;改变关键变量测算方法、样本选择、模型估计方法后研究结论依然稳健。进一步作用机制检验表明,进口竞争对企业产品出口加成率的"价格效应"不明显,但"成本效应"和"质量效应"的作用显著,特别是通过提高异质性产品质量、降低同质性产品边际成本影响出口加成率。相对而言,进口竞争对出口中的外资和民营企业、进口企业、高市场竞争程度产品企业,以及一般贸易产品和资本品的出口加成率有更强的影响效应。本文识别了进口竞争影响出口加成率的差异化机制,发现了进口竞争影响我国企业产品出口加成率的质量升级效应,表明进口竞争有利于提升我国企业产品的国际市场势力。

With Reference to De Loecker et al.(2016), this paper measures markup in export market of Chinese firm’s product after calculating the input of production factors at firm-product level. The paper empirically studies the effects of import competition, which is induced by reduction of output import tariff, on export markup, distinguishing product differential degree. In total, import competition significantly raises firm products’ export markup, and this effect is evident among heterogeneous products, not among homogeneous products. The results are robust to different econometric methods. The mechanism empirical tests prove import competition does not suppress export price directly;but significantly improves quality and markup of heterogeneous products through"quality enhancing effect";and also has an effect on markup of homogeneous products through"marginal cost decreasing effect". Besides, import competition has bigger effects on export markup for foreign-owned or private firms, import firms, firms in competitive industries, ordinary trade products and consumption products. This paper studies a new channel of"quality enhancing effect",through which import competition raises export markup, and concludes that import competition is an efficient way to improve export competitiveness.