新基建发展对产业升级的影响机制研究

新基建作为现代化基础设施体系的重要组成部分，已经成为中国经济高质量发展的重要支撑。基于2015—2021年中国71个城市的面板数据，构建双向固定效应、中介效应和调节效应三种回归模型，实证检验新基建发展对城市产业结构水平的影响及内在机制。研究发现：新基建发展能促进产业高级化水平，改善不合理的产业结构状态，提升产业合理化水平；新基建通过发展物联网和激励城市研发创新两种间接路径对产业结构转型升级产生积极影响；新基建对产业结构水平的影响受到地方政府干预行为的调节作用，在地方政府合理的行政管理下，新基建对产业转型升级的积极作用更为明显；新基建发展对产业结构水平的提升作用具有区域异质性和城市规模异质性，在中西部地区和大城市地区的作用效果更为明显。

Investigation on the Impact Mechanism of New Infrastructure on Industrial Upgrading

As an important component of the modern infrastructure system, new infrastructure has become an important support for China''s high-quality economic development. Based on panel data of 71 cities in China from 2015 to 2021, three regression models of two-way fixed effect, intermediary effect and moderating effect were constructed to empirically test the impact of new infrastructure development on the level of urban industrial structure and the underlying mechanism. It is found that new infrastructure development can promote the level of industrial sophistication, improve the state of unreasonable industrial structure and enhance the level of industrial rationalisation.New infrastructure has a positive impact on the transformation and upgrading of industrial structure through two indirect paths: developing the Internet of Things and stimulating urban R&D and innovation. The impact of new infrastructure on the level of industrial structure is moderated by the intervention behaviour of local governments, and under reasonable local government.The effect of new infrastructure development on the upgrading of industrial structure level is regionally heterogeneous and city scale heterogeneous, and the effect is more obvious in the central and western regions and big city areas.