中国高铁、贸易成本与企业出口研究

China's high-speed rail has an increasingly significant impact on economic and social development. This paper uses data on China's high-speed rail, customs, industrial enterprises, and cities from 2000 to 2011, regarding the opening of high-speed rail as a quasi-natural experiment. From the perspective of changes in trade costs, it examines the impact of China's high-speed rail on enterprise exports and its mechanism of action. The results show that the exports of enterprises in cities with high-speed rail have increased by 12.7%. Drawing on Faber (2014) to construct a "minimum spanning tree" as an instrumental variable to deal with endogeneity problems and conducting a series of robustness tests, the conclusion always holds. In terms of mechanism research, referring to the methods of Donaldson & Hornbeck (2016) and Lin (2017) to introduce and calculate "market access", it is found that the opening of high-speed rail promotes enterprise exports by reducing fixed trade costs. Heterogeneity analysis shows that the opening of high-speed rail significantly increases the extensive margin of enterprise exports, has a greater promoting effect on capital- or technology-intensive industries, time-sensitive products, cities in the eastern region, and cities where high-speed rail directly reaches ports, and the effective impact range on enterprise exports is approximately the road distance of 30 kilometers from the high-speed rail station to the center of its city. The research in this paper provides useful implications for optimizing the construction planning of China's high-speed rail and promoting the transformation and upgrading of the enterprise export structure.

中国高铁对经济社会发展产生日益显著的影响。本文使用2000—2011年中国高铁、海关、工业企业和城市等数据,将开通高铁视作一项准自然实验,基于贸易成本变动视角,考察中国高铁对企业出口的影响及其作用机制。结果显示,开通高铁城市的企业出口提高了12.7%。借鉴Faber（2014）构造"最小生成树"作为工具变量处理内生性问题,以及进行系列稳健性检验,结论始终成立。在机制研究方面,参考Donaldson&Hornbeck（2016）和Lin（2017）的方法引入和计算"市场准入",发现开通高铁通过降低固定贸易成本促进了企业出口。异质性分析发现,开通高铁显著提高了企业出口的扩展边际,对资本或技术密集型行业、时间敏感性产品、东部地区城市和高铁直达港口的城市出口促进作用更大,对企业出口的有效影响范围约是高铁站到其所在城市中心30公里的道路距离。本文研究为优化中国高铁修建规划和促进企业出口结构转型升级提供了有益启示。