Nonlinear impacts of the configuration elements of life services on spatial vitality in the online-merge-offline context: A case study of Shanghai, China

Despite the growing prevalence of online-merge-offline life services and increased spatiotemporal flexibility in human activities, few studies examine how social media platforms and spatial layout elements jointly influence spatial vitality, hindering sustainable development in the digital era. To address this gap, this study employs Light Gradient Boosting Machine (LightGBM) interpreted by SHapley Additive exPlanations (SHAP) to analyze the nonlinear impacts of Internet word-of-mouth (IWOM) and spatial layout elements of life services on spatial vitality in Shanghai. Key findings reveal that: (1) IWOM drives a shift in life service access from location determinism to a digital visibility-driven mode through spatial activation and interaction, thereby redistributing spatial vitality; (2) The impact of IWOM varies significantly by service type: retail commerce and convenience services exhibit the strongest enhancement effects, with both showing a minimum threshold in activating vitality; (3) Significant interactive effects exist, particularly between plot ratio and IWOM of multiple life services, reinforcing the trend of online service penetration into vertical spaces. These findings advance the theoretical understanding of how information and communication technologies (ICT) enhance spatial vitality and provide a practical basis for guiding the digital transformation of life service configuration.