Accessibility is usually evaluated using indicators calculated from spatial data. However, perceived accessibility, defined as the perceived potential to participate in spatially dispersed opportunities, is often poorly reflected by these calculated measures. This paper sets out to explain the mechanisms that lead to these mismatches. A conceptual model is constructed to establish what factors shape perceived accessibility. A schematic framework shows that mismatches between a calculated indicator and perceptions can stem from inaccuracies in awareness as well as from inaccuracies in the measure if the measure fails to take account of the subjective evaluations of accessibility components. When evaluating the performance of land-use and transport system configurations, calculated measures based on spatial and transport data only serve as proxies for how accessibility is actually experienced. This paper argues that bringing perceived accessibility to the fore of accessibility-based planning, by acknowledging and evaluating potential mismatches with calculated accessibility indicators, will advance the evolution from mobility-based to accessibility-based planning.

通常使用从空间数据计算的指标来评估可达性。然而，感知可达性，定义为参与空间分散机会的感知潜力，往往无法通过这些计算量度来反映。本文着手解释导致这些不匹配的机制。构建一个概念模型来确定影响感知可达性的因素。一个示意性框架表明，计算指标与感知之间的不匹配可能源于意识的不准确，以及如果测量未能考虑可访问性组件的主观评估，则源于测量的不准确。在评估土地利用和运输系统配置的性能时，基于空间和交通数据的计算测量值仅作为实际体验可达性的代理。本文认为，通过承认和评估与计算的可达性指标的潜在不匹配，将感知可达性置于基于可达性的规划的前沿，将推动从基于移动性到基于可达性的规划的演变。