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.

翻译：可达性对于设计包容性城市系统至关重要。然而，试图通过单一通用指标来概括可达性的复杂性，往往限制了其在设计、测量和治理等不同领域的有效应用。基于Bertolini以及Levinson与Wu的前期研究，我们强调可达性包含三个关键维度。具体而言，我们提出一个概念框架，通过三个主要维度定义可达性：邻近性（涉及主动的、短距离可达的本地服务和设施）、机会（指快速获取相关非本地资源，如就业机会或主要文化场所）与价值（涵盖特定兴趣点的整体质量及个人重要性）。尽管提升可达性通常有益，但不同用户和情境存在独特的权衡取舍，使得"一刀切"的解决方案既不切实际也不可取。我们的框架为建模可达性奠定了一种定量化、整合性的基础。它考虑了各维度间的复杂交互作用，并有助于在不同背景下进行更系统的分析、比较与决策。