Development of the Digital Economy and the Upgrading of Residents’ Consumption Structure: Spatial Spillovers and Heterogeneous Evidence from Chinese Provinces

The existing research has rarely integrated within-province associations, interprovincial spatial linkages, and multidimensional heterogeneity when examining how digitalization is related to increasing household consumption. Using a balanced panel of 30 provincial-level regions in China for 2011–2023, compiled from national and provincial statistical yearbooks (CSMAR) and the Peking University Digital Financial Inclusion Index, this study constructs a 0–1 digital economy development index with entropy-weighted TOPSIS. Two-way fixed effects estimate the average within-province relationship; global and local Moran’s I and a spatial Durbin model evaluate spatial dependence and decompose direct, indirect, and total effects. Panel quantile regressions and alternative spatial weight matrices serve as robustness checks, whereas instrumental variables and double/debiased machine learning provide supplementary identification evidence. Digital economy development is positively associated with consumption upgrading in the baseline model. Under economic distance weights, the direct, indirect, and total effects are all significantly positive, although their structure differs across consumption categories, urban and rural groups, regions, and temporal stages. The findings support combining digital infrastructure with service capacity, skills, consumer protection, and interprovincial governance while avoiding uniform policy prescriptions across regions.