Digital infrastructure and industrial integration: An assessment of the coupling coordination effect between digital and real economy in China

The synergy between digital infrastructure and industrial sectors is pivotal for fostering high-quality economic growth and reshaping development paradigms. Assessing the coupling coordination between the digital and real economy is essential for comprehending China's developmental pattern and informing relevant policy. Under this background, the paper firstly constructs a comprehensive measurement framework, where the digital economy is measured from three dimensions: digital infrastructure, digital industrialization and industrial digitization; and the real economy is quantified from six industries. Utilizing the panel data of 31 Chinese provinces in 2011-2023, we developed a novel coupled coordination degree model refined with mutual information to assess the integration level of the digital and real economy (IDR). To uncover the spatial differences and dynamic evolution of this integration, we applied Dagum's Gini coefficient decomposition, kernel density estimation, global and local Moran's I, and spatial Markov chain analysis. Our findings reveal a substantial improvement in the IDR across China during the study period. However, pronounced regional inequality persists, with inter-regional differences being the primary contributor to the overall differences. The distribution dynamics show significant cross-province heterogeneity and a clear tendency of spatial agglomeration, as evidenced by a significant positive spatial correlation. The results underscore the necessity for policies that not only advance digital infrastructure deployment but also strategically foster its deep integration with traditional industries, considering the distinct spatial patterns and regional imbalances identified.