Inputs, networks and quality-upgrading: Evidence from China in India
利用中国加入WTO作为供给冲击，研究发现印度企业因获得更高质量投入品而提升产品质量，且这种升级沿供应链传导，放大初始效应高达75%。
This paper exploits China's accession to the WTO to investigate the impact of a supply shock on quality across the Indian production network. After controlling for increased import competition, including in downstream and third-country markets, and for new export opportunities, we find that a fall in input tariffs raises revenue, quality and prices, whilst lowering quality-adjusted prices and the probability of product exit – consistent with a simple model of multi-product manufacturers gaining access to higher-quality components. Upgrading persists for at least ten years; at the peak in 2010, products with a 10% higher pre-accession input tariff, and hence a larger post-accession fall in tariffs, have 5.3% higher quality. This in turn raises quality further down the supply chain, with input-output linkages amplifying the one-step effect by up to 75%. These results highlight a potential beneficial impact of the “China shock” in developing countries, namely supply-driven quality upgrading.