交通基础设施如何促进资本流动——基于高铁开通和上市公司异地投资的研究

How Does Transportation Infrastructure Affect Capital Flows——A Study from High-speed Rail and Cross-region Investment of Listed Companies

交通基础设施影响经济增长和地区经济差距的一个重要渠道是促进了跨地区的资本流动。本文基于2006—2018年高铁开通和上市公司异地投资数据,研究了交通基础设施对跨地区资本流动的影响。为了解决高铁开通的内生性问题,本文基于各城市地理位置构建了工具变量。实证结果表明,高铁连通之后,上市公司赴异地投资的数量明显增加。与此同时,高铁对城市间资本流动的促进作用具有方向上的不对称性,高铁开通导致资本从中小城市净流入大城市。机制分析表明,高铁开通降低资本流动障碍后,资本之所以会净流入大城市,是因为大城市有更大的本地市场规模,生产的规模报酬递增效应、产业集聚和技术溢出使企业在大城市有更高的生产率。这一结论从企业投资流向的角度验证了高铁开通存在"虹吸效应",也为"卢卡斯之谜"提供了新的证据。

An important channel for transportation infrastructure to influence economic growth and regional economic disparity is to facilitate capital flows across regions.Based on the opening of high-speed rail and listed companies’investment data from 2006 to 2018,this paper estimates the effects of transportation infrastructure on cross-region capital flows.To solve the endogenous problem of high-speed rail opening,we construct instrumental variables based on the geographical location of each city.We find that the connection between cities by high-speed rail increases the number of listed companies’cross-region investment significantly.Moreover,high-speed rail has asymmetric effects on facilitating capital flows between cities,leading to a net flow of capital from small-medium cities into large cities.Mechanism analysis shows that with reduced capital flow barriers after the opening of highspeed rail,capital flows into large cities as a result of larger market size and higher productivity brought by increasing returns of scale,industrial agglomeration and positive spillover of technology.This conclusion confirms the existence of"siphonic effect"from the perspective of firm investment flows,and also provides new support for the"Lucas Paradox".