The public transport system only serves its true purpose when people living in the region have adequate and direct access to its services. Rail systems, including light rail, metro, urban, suburban, and long-distance trains, are the key fixed structural elements of any transport system that provide faster access for both shorter and longer trips and are regarded as a more efficient and environmentally friendly option to move a larger number of passengers than road transport. However, it is not feasible in terms of investment and financial sustainability to provide rail services everywhere, especially in rural zones. Thus, connectivity with all the other available (active and motorized) modes is crucial to improve accessibility and reduce inequities. In this paper, we developed a methodology to quantify and contrast the access to the existing rail services between zones of a metropolitan area and corresponding inequities. We considered not only the usually analyzed active modes, pertaining to a certain level of proximity to the rail stations, but also motorized modes (e.g., car and bus) that can enable the connection to rail services where these are not easily accessible by walking or cycling. First, the accessibility to the existing rail stations is quantified using place-based gravity measures, considering the travel times for the complementary modes with and without incorporating the stations' attractiveness, measured by service frequency. Second, the global inequity levels of the spatial distribution of the rail network in the metropolitan area are evaluated using the Gini index. Third, local inequities, at a scale of small census blocks, are measured considering the access (supply) and the population (potential demand). While the local-scale analysis allows to identify the most unfavored zones, the global inequities by complementary modes aim to inform targeted strategies to improve the integration of those modes with rail services. The methodology was applied to the Metropolitan Area of Porto, Portugal, where we observed a non-uniform distribution of rail services and a decrease in access towards the periphery. However, considering the population living in each zone, both underserved and well-served zones are mostly present in the most populated/central areas.

中文翻译：

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通过补充机动化和主动模式获得铁路服务的公平性


只有当居住在该地区的人们能够充分、直接地获得公共交通服务时，公共交通系统才能发挥其真正的作用。铁路系统，包括轻轨、地铁、城市、郊区和长途列车，是任何交通系统的关键固定结构要素，为短途和长途旅行提供更快的通达，并被视为更高效、更环保的选择运送比公路运输更多的乘客。然而，从投资和财务可持续性角度来看，在各地（尤其是农村地区）提供铁路服务并不可行。因此，与所有其他可用（主动和机动）模式的连接对于提高可达性和减少不平等至关重要。在本文中，我们开发了一种方法来量化和对比大都市区之间现有铁路服务的获取情况以及相应的不平等。我们不仅考虑了通常分析的与火车站一定程度接近的主动模式，还考虑了机动模式（例如汽车和公共汽车），这些模式可以在步行或步行不易到达的地方实现与铁路服务的连接。骑自行车。首先，使用基于地点的重力测量来量化现有火车站的可达性，考虑互补模式的旅行时间，考虑或不考虑车站的吸引力，并通过服务频率来衡量。其次，利用基尼指数评估大都市区铁路网空间分布的全球不平等程度。第三，在小规模人口普查范围内，考虑准入（供应）和人口（潜在需求）来衡量当地的不平等。 虽然地方规模的分析可以确定最不利的区域，但互补模式的全球不平等旨在为有针对性的战略提供信息，以改善这些模式与铁路服务的整合。该方法适用于葡萄牙波尔图大都市区，我们观察到该地区铁路服务分布不均匀，且通往外围地区的通达率有所下降。然而，考虑到居住在每个区域的人口，服务欠缺和服务良好的区域大多出现在人口最多/中心区域。