Rapid urbanization has presented many challenges, notably spatial imbalances between the transit supply and demand within cities. The inequitable distribution of transit supply, which include the transit infrastructure and services, may lead to formation of areas where transit is under provisioned. This work aims to develop an enhanced framework for measuring spatial disparities in accessing transit systems by combining established concepts of Public Transport Accessibility Levels (PTAL) and transit gap. The proposed framework incorporates PTAL as a supply indicator and transit dependent population as the demand indicator while estimating the transit gap. PTAL takes into account the intricate relationship between transit infrastructure and transit services, an aspect that was overlooked by the previous studies on transit gap. Inclusion of PTAL enhances the transit gap evaluation method by offering a deeper understanding and a holistic perspective on the transit system. We demonstrate the proposed approach with an application in Singapore. Additionally, we propose a new classification system based on PTAL and transit gap to distinguish areas where high transit gap is a result of very high demand rather than poor supply. Results show that 44.82 % of the transit dependent population in Singapore lives in high transit gap area out of which 4.69 % population stays in transit desert zones, where supply is poor, and 40.13 % lives in transit stressed zone, where demand is very high. The study also developed a simple decision framework based on PTAL and transit gap scores to suggest effective policy measures for reducing the spatial disparity in transit system accessibility. The findings from the work can aid policymakers and transport planners in land-use and transport planning of cities.

中文翻译：

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通过整合公共交通无障碍等级 （PTAL） 和交通差距，增强交通无障碍评估框架


快速城市化带来了许多挑战，尤其是城市内部交通供需之间的空间失衡。公交供应（包括公交基础设施和服务）分配不均可能导致形成公交供应不足的区域。这项工作旨在通过结合公共交通无障碍等级 （PTAL） 和交通差距的既定概念，开发一个增强的框架来衡量进入交通系统的空间差异。拟议的框架将 PTAL 作为供应指标，将依赖公交的人口作为需求指标，同时估计公交差距。PTAL 考虑了交通基础设施和交通服务之间的复杂关系，这是之前关于交通差距的研究中所忽视的方面。纳入 PTAL 通过提供对交通系统的更深入理解和整体视角来增强交通差距评估方法。我们通过新加坡的一个应用程序演示了所提出的方法。此外，我们提出了一种基于 PTAL 和运输缺口的新分类系统，以区分高运输缺口是由于需求非常高而不是供应不足而导致的区域。结果显示，新加坡 44.82% 的交通依赖人口生活在高交通缺口地区，其中 4.69% 的人口居住在供应不足的过境沙漠地区，40.13% 的人口生活在需求非常高的过境紧张地区。该研究还开发了一个基于 PTAL 和交通差距分数的简单决策框架，以提出减少交通系统可达性空间差异的有效政策措施。 这项工作的结果可以帮助政策制定者和交通规划者进行城市的土地利用和交通规划。