39.6SOC-PHApr 29
The dimensions of accessibility: proximity, opportunities, valuesMatteo Bruno, Bruno Campanelli, Hygor Piaget Monteiro Melo et al.
Accessibility is essential for designing inclusive urban systems. However, the attempt to capture the complexity of accessibility in a single universal metric has often limited its effective use in design, measurement, and governance across various fields. Building on previous work by Bertolini and by Levinson and Wu, we emphasise that accessibility consists of three key dimensions. Specifically, we introduce a conceptual framework that defines accessibility through three main dimensions: Proximity (which pertains to active, short-range accessibility to local services and amenities), Opportunity (which refers to quick access to relevant non-local resources, such as jobs or major cultural venues), and Value (which encompasses the overall quality and personal significance assigned to specific points of interest). While it is generally beneficial to improve accessibility, different users and contexts present unique trade-offs that make a one-size-fits-all solution neither practical nor desirable. Our framework establishes a foundation for a quantitative and integrative approach to modelling accessibility. It considers the complex interactions among its various dimensions and facilitates more systematic analysis, comparison, and decision-making across diverse contexts.
24.8SOC-PHApr 1
Car Dependency in Urban AccessibilityBruno Campanelli, Francesco Marzolla, Matteo Bruno et al.
To achieve net-zero emissions, cities must transition away from reliance on private vehicles. However, car-centric urban growth has transformed the automobile from a convenience tool into a necessity for accessing essential services, creating significant "car dependency". This study introduces a novel Car Dependency Index (CDI) that quantifies the accessibility gap between private and public transport across 18 cities in Europe and North America. Utilising high-resolution geospatial data and numerical simulations, we reveal pronounced spatial inequalities, showing that car dependency remains a primary driver of car ownership even when accounting for income. A ``what-if" simulation of the planned metro expansion in Rome predicts a reduction of approximately 60,000 commuting vehicles, yet highlights that isolated interventions have localised impacts. We conclude that systemic, network-level transit expansions are essential to dismantle car-based systems and foster equitable, sustainable urban mobility. Our framework provides policymakers with an objective, scalable tool to identify viable areas for car-free zones and target infrastructure investments effectively.