The metro is the backbone of the transport system in many cities. Analyzing the built-
environment correlates of metro ridership is crucial for transit-oriented development (TOD)
planning and practice. Although numerous studies went along this line, they have rarely
considered the non-linearity and temporal heterogeneity in the association of metro
ridership with the built environment. After collecting transit smart card data, geo-data, and
mobile phone signal data, this study adopts the random forest model to reveal the complex …