• Spatiotemporal variations are thoroughly examined using advanced geospatial indices. • Spatial disparities between central and suburban areas are found. • The public transport system does not consider the commuters’ patterns. • “Time-based inequity” does not emerge, inequities are constant throughout the day. • Night-time services, increased frequency and improved coverage should be prioritized. Urban public transport systems often exhibit uneven accessibility across space and time, raising critical concerns about transport equity and particularly about captive travelers (i.e., older adults and zero-car households). While current studies frequently assess public transport accessibility or equity at static time points, limited evidence exists on how spatiotemporal variations jointly shape horizontal and vertical inequities throughout the day. Using data from the Athens Metropolitan Area (AMA), Greece, this paper investigates in detail the spatiotemporal variations in public transport accessibility and equity for captive travelers throughout a typical day. The Gini coefficient (a measure of inequality in the distribution of accessibility) is exploited for assessing horizontal equity, while vertical equity is evaluated through the Concentration Index (measuring whether accessibility is disproportionately distributed among disadvantaged groups) and Bivariate Local Moran’s I (a spatial autocorrelation statistic identifying spatial clusters between accessibility and the distribution of captive travelers). Findings reveal significant variations in public transport accessibility, with early morning and evening hours exposing low accessibility values, whereas morning and afternoon illustrate better conditions. These variations declare a mismatch between the supply side of public transport and the demand in AMA. Delving into the temporal aspect, the persistence of inequity throughout the day suggests a structural rather than a temporal equity problem, raising serious concerns about the city’s public transport system. These intriguing outcomes are also analyzed through a spatial lens identifying serious geographical disparities between central and suburban areas. This analysis unveiled spatial clusters of low accessibility and high proportion of the least well-off. Apparently, spatial disparities are more pronounced than temporal ones. Building upon the results, several indicative policy implications are outlined, such as providing extended night-time services, improving frequency during very early and evening hours, expanding the public transport system (mainly the metro network) to suburban areas and the outskirts or even rethinking the distribution of land uses in these underserved areas. The study’s findings could be meaningful to both academia and planners that strive to ensure public transportation is truly accessible and equitable throughout the day, accommodating the needs of captive travelers.
Tsigdinos et al. (Wed,) studied this question.