Journal of Statistics and Information

党的二十届三中全会提出“健全新型基础设施融合利用机制，推进传统基础设施数字化改造”,以宽带网络为核心的数字基础设施建设重塑城市创新形态，对推动中国式现代化高质量发展具有关键作用。基于2011—2020年284个城市的面板数据，以“宽带中国”试点政策为准自然实验，兼论结构优化和资源配置视角，利用多时点DID模型实证检验数字基础设施建设赋能城市经济高质量发展的作用效应和实现路径。研究发现，“宽带中国”试点城市建设有助于城市经济高质量发展，且随着时间推移，政策效应呈边际递增趋势。政府注意力配置、城市创新活力和数字金融发展是“宽带中国”试点城市建设助推经济高质量发展的重要机制，其中城市创新活力机制在该过程中发挥主导作用。“宽带中国”试点政策对高水平数字发展城市、大规模城市、东部地区城市、南方地区城市、城市群城市和服务型城市经济高质量发展的提升作用更为显著。“宽带中国”政策效应的发挥受地区产业结构特征和资源配置效率的影响，结构优化和资源配置对“宽带中国”政策效果存在正向调节作用。据此，提出因地制宜布局宽带基础设施建设、构建数字经济区域合作平台、优化地区产业结构和资源配置等政策建议，促进地方政府积极推进“宽带中国”战略，优化数字基础设施整体布局，塑造经济高质量发展新动能新优势。

The Third Plenary Session of the 20th Central Committee of the Communist Party of China proposed to “improve the mechanism for the integrated application of new infrastructure and accelerate the digital transformation of traditional infrastructure.” The development of digital infrastructure, with broadband networks as its core, reshapes urban innovation patterns and plays a pivotal role in promoting high-quality development within the context of Chinese-style modernization.Based on panel data from 284 cities spanning the period 2011 to 2020,this study employs the “Broadband China” pilot policy as a natural experiment.By considering the perspectives of structural optimization and resource allocation, this study utilizes a multi-point Difference-in-Differences model to empirically examine the impact and implementation pathways of digital infrastructure construction on empowering high-quality urban economic development.The findings indicate that the establishment of “Broadband China” pilot cities significantly promotes the high-quality development of urban economies, with the policy effect exhibiting a marginal increasing trend over time.Government attention allocation, urban innovation vitality, and the development of digital finance serve as critical mechanisms through which “Broadband China” pilot city construction enhances high-quality economic development, with urban innovation vitality playing a predominant role in this process.The “Broadband China” pilot policy has a more pronounced promoting effect on high-quality economic development in cities with high levels of digital development, large-scale cities, cities in the eastern and southern regions, cities within urban agglomerations, and service-oriented cities.The policy's effectiveness is influenced by regional industrial structure characteristics and resource allocation efficiency.Structural optimization and efficient resource allocation exert a positive moderating effect on the policy effects of “Broadband China.” Based on these insights, the study offers policy recommendations for local governments to actively advance the “Broadband China” strategy, optimize the overall layout of digital infrastructure, and cultivate new drivers and advantages for high-quality economic development.