Accessibility via public transport through gravity models based on open data

Efficient urban facility access is crucial for enhancing residents' well-being and quality of life. This study examines public transport accessibility to essential facilities in Rome, such as high schools and hospitals, using gravity models based on open data sources, like OpenStreetMap and GTFS. Two versions of the gravity model are compared: an origin constrained and a doubly constrained. The latter can consider the capacity of facilities as a strict constraint, offering thus a more realistic assessment of accessibility. The findings highlight the correlation of public transport quality and urban accessibility, showing how variations in public transport supply affect the weighted average time to reach services like healthcare, education, and leisure. This approach reveals specific zones needing improvement and provides a valuable tool for predicting the impact of future changes in the transport network with respect to social equity. An online platform has been developed to allow a readily available application of this methodology to boost active citizenship and proactive decision making.