Should transit-oriented development consider station age effects?

Promoting transit-oriented development (TOD) through the built environment and transport interventions is an essential planning strategy for achieving urban sustainable objectives. Yet, existing studies largely neglect the critical effects of station age on the relationship between the built environment and metro ridership. This study fills this gap by examining how the impact of the built environment on metro ridership varies by station age in Shanghai, China. We apply machine learning methods to identify key determinants of metro ridership and examine nonlinear associations across three station age intervals. The results suggest: (1) the effects of the built environment and metro ridership are not homogeneous among different station ages; (2) the transport-related built environment factors contribute more to metro ridership at the early stage period, while the land use-related built environment variables more profound at latter stages. These insights provide planners with stage-specific guidance on tailoring built environment interventions for TOD.