Measuring spatial equity between metro accessibility and public service demand in Shanghai using a data-driven framework

Urban metro systems play a central role in shaping mobility opportunities and access to essential public services, yet these benefits are not always shared equitably across cities. This study evaluates equitable mobility in Shanghai by examining how metro-based accessibility to public services aligns with actual passenger demand. We develop a multidimensional accessibility index for each station based on travel time to diverse public services and integrate it with passenger flow data to construct a local alignment index. A Lorenz curve and Gini coefficient capture system-wide distributional patterns. The analysis shows clear and persistent inequities: central stations maintain strong alignment between accessibility and demand, while many peripheral stations consistently face high demand but limited access. The system-wide Gini coefficient of 0.348 reflects a notable imbalance in the distribution of accessibility benefits. These results highlight inequitable spatial pattern embedded in the metro network's spatial design. The study introduces a replicable, behaviour-sensitive framework that links actual mobility patterns with public service accessibility. It also provides actionable evidence for spatial-equity-oriented metro planning, emphasizing the need for targeted improvements in underserved areas and stronger coordination between land-use and transit development. Together, these contributions support more inclusive and equitable urban mobility planning.