交通基础设施建设与区域间市场整合——以高速公路为例

Transportation Infrastructure and Interregional Market Integration:A Case Study of Highways

本文以高速公路为例,实证检验交通基础设施建设的市场整合效应。基于1998~2017年高速公路数据,结合静态路网,本文识别了高速公路建设对城市间驾驶时间的影响,分析了其对市场整合的作用。研究发现,高速公路建设带来的交通时间成本下降使得城市间相对价差波动性显著降低,促进了跨区域市场整合。在剥离了初始交通时间成本的影响后,其促进市场整合的影响幅度接近省际边界效应。机制分析表明,高速公路建设提高了生产要素流动性,其对城市间人口迁移的提升效应接近迁移率均值;提升了城市间贸易流量,总效应超过8.87%;促进了区域间生产分工,加强了产业前后向关联。研究还发现,高速公路建设改善了省际边界效应,对跨越省界的城市间市场整合效应更显著。

Since the beginning of the reform and opening-up,particularly after the tax-sharing reform in 1994,the phenomenon of market segmentation in China has garnered widespread attention.Most scholars believe that segmented markets are detrimental to economic development. In addressing the question of how to promote market integration, existing research has predominantly focused on institutional factors. It emphasizes breaking market segmentation caused by local competition through institutional reforms. However,little attention has been given to more foundational frictional factors,particularly the role played by transportation costs.The extensive and interconnected nationwide transportation network,a prerequisite for strengthening regional communication and trade,is likely a crucial factor in promoting regional market integration.Unfortunately,there is a lack of literature exploring how interregional transportation conditions influence market integration domestically. The existing studies at the provincial level,focusing on either existing or invested provincial-level road infrastructure,have not provided a conclusive answer to this question.Given the pivotal role of highways in the freight transportation system(with freight accounting for consistently over 70%),this study concentrates on the impact of constructing highways on interregional market integration.By utilizing data on highways from 1998 to 2017 and incorporating static road networks,we calculated the annual minimum driving time between any two cities. Controlling for city pairs and year fixed effects,changes in driving time depended solely on the expansion of highway networks. This method allowed us to assess the impact of reduced driving time on various factors. To investigate the influence of highway construction on interregional market integration, we collected various price indices for commodity retail and consumer consumption for prefecture-level cities. We calculated the relative price difference of the same commodity between two cities and then the standard deviation of relative price differences across commodities to measure the degree of market segmentation. The empirical results demonstrated that a greater reduction in intercity transportation costs due to highways led to lower volatility in relative price differences,indicating higher market integration. After removing the impact of initial transportation costs, the effect of reduced transportation time on market integration closely resembled provincial border effects. We also observed that highways crossing provincial borders have stronger market integration effects, indicating that transportation infrastructure can mitigate administrative barriers.We proposed three possible mechanisms to explain the observed effects—increased mobility of production factors, enhanced interregional trade volume, and promotion of regional production specialization. Using microdata from the national census,we calculated intercity migration rates to test the mechanism of production factor mobility. The findings revealed that highway construction facilitated intercity population migration—a statistically and economically significant effect that approached the mean migration rate. Subsequently,we used recently compiled city-level interregional input–output data to examine the trade mechanism. The results indicated that highway construction significantly increased intercity trade volume,with a 10% reduction in transportation time associated with at least a 1.479%increase in intercity trade volume. Over the study period,highway construction contributed to an overall increase of more than 8.87% in trade volume. Finally,we calculated the production specialization index based on employment figures from the statistical yearbook for each city and industry,finding that highway construction significantly reduced the similarity in industrial structure,deepening interregional industrial specialization. Even within the manufacturing sector,highway construction strengthened the intercity industrial connection,promoting further specialization in manufacturing.This study systematically explores how transportation infrastructure influences regional market integration at the city pair level. It addresses limitations in existing domestic literature,which frequently oversimplifies regional analysis by concentrating solely on intra-regional transportation and overlooking inter-regional dynamics. The results provide empirical support for the role of transportation infrastructure in establishing a unified national market and facilitating seamless nationwide circulation.