数字基础设施建设对地区经济差距的影响——基于“宽带中国”战略的准自然实验

The Impact of Digital Infrastructure Construction on Regional Economic Gap:A Quasi-Natural Experiment Based on the “Broadband China” Strategy

数字基础设施作为中国政府当前稳增长、调结构、惠民生的重点投资方向,其将如何影响地区收入分配格局已然成为中国式现代化背景下共同富裕目标实现的重要议题。本文基于2004—2020年中国285个地级城市面板数据,将“宽带中国”战略作为一项准自然实验,采用双重差分模型,探究数字基础设施建设对地区经济差距的影响及其传导机制,并进一步考察城市区位、互联网发展水平、交通基础设施发达程度的异质性。研究发现,第一,“宽带中国”战略实施有助于缩小地区经济差距,经过一系列稳健性检验和内生性处理后,结论依然成立。第二,“宽带中国”战略通过促进技术创新缩小地区经济差距。第三,在东部、互联网发展水平高、交通基础设施发达地区,“宽带中国”战略实施对地区经济差距的缩小作用更明显。本研究有助于厘清中国数字基础设施建设与地区经济差距之间的关系,并为缩小地区经济差距提供决策依据。

Digital infrastructure is a key investment direction of the Chinese government to achieve steady growth,adjust structure,and improve livelihood,and how it will affect the regional income distribution pattern has become an important issue to achieve the goal of common prosperity against the background of Chinese modernization.However,the existing studies mainly investigate the impact of transportation infrastructure and the digital economy on income distribution,explore the impact of digital infrastructure on the urban-rural income gap,and rarely pay attention to the regional income distribution effect of digital infrastructure,and the relevant research conclusions remain inconsistent.This paper draws on the analytical framework of neoclassical economic theory,builds a two-region and two-sector model,and expounds on the transmission path of digital infrastructure construction affecting the regional economic gap from the perspective of technological progress.It is found that digital infrastructure construction can affect the regional economic gap by promoting technological progress.The “Broadband China” strategy is regarded as a quasi-natural experiment,and the difference-in-differences model is used for empirical tests.The study shows that the implementation of the “Broadband China” strategy can help narrow the regional economic gap,and this conclusion remains valid after alleviating the endogenous problem and other robustness tests.Given the theoretical analysis,this paper selects technological progress as the mechanism variable for empirical tests.The research results show that technological progress is a necessary condition for the “Broadband China” strategy to narrow the regional economic gap,which is consistent with the theoretical analysis conclusion.In addition,this paper further examines the heterogeneity of different urban locations,Internet development levels,and transportation infrastructure levels,and finds that the “Broadband China” strategy has a more significant inhibitory effect on the economic gaps in the eastern region,and regions with high Internet development levels.The policy implications of this paper are as follows in order to narrow the regional economic gap,we should pay more attention to the scientific layout of digital infrastructure construction in the future,give play to the role of digital infrastructure as a link,and strengthen cooperation and exchanges between the central and peripheral regions;we should give full play to the effect of technological progress of digital infrastructure to promote the economic development of peripheral regions;we should strengthen the digital infrastructure construction in the western region and regions with low Internet development levels and underdeveloped traditional transportation infrastructure,and promote the rational distribution of resources among regions.