城市公共交通服务水平研究回顾和展望

系统梳理交通系统服务水平概念的发展，指出服务水平的内涵已从道路设计层面拓展到多方式、运营领域，提出公共交通服务水平构成要素分为效率、舒适度两大部分，两者分别主要关联于运输产品设计和出行者主观感受。回顾和评述了公共交通系统服务水平的评价与分级研究，这些评价方法与服务水平构成要素相对应，分为以运输效率为主的客观评价和以感受调查与 分析为主的主观评价；指出了由于国情差异，既有的以美国运输研究委员会发布的相关服务水平分级未必具有普适性。之后，回顾了我国公共交通服务水平的研究与实践，指出当前我国既有规范中未明确公共交通服务水平的内涵、缺乏适用于我国的系统分级。从公共交通服务水平的形 成具有全局性、评估因素的复杂性、涉及乘客出行环节多、需要政府支持投资等角度剖析了服务水平改善的难点。指出了未来值得深入研究的3个领域：基于全出行链的公共交通服务水平内涵及评估；考虑服务质量不均衡分布的公共交通系统服务水平测算方法；关注乘客感知差异化的满 意度调查和基于现代信息技术的服务水平评估方法。最后，提出了以服务水平为抓手推进公共交通运行质量与效率建设战略的建议。

A Review and Prospect of Urban Public Transit Level-of-Service Research

This paper summaries the evolution of the concept of level- of- service (LOS) in transportation system and describes the characteristics of LOS in different stages. The implication of LOS has expanded from merely focusing on road design to incorporate multi-modal and wide operational areas. The LOS of public transit include two major components: transport efficiency and passengers' comfort, which are respectively associated with transport product design and passengers' perception to the services. The paper further reviews the LOS evaluation and classification research in the public transport system. These evaluation methods are relevant to the LOS elements and can thus be divided into the objective evaluation that are based upon transport efficiency and the subjective evaluation that focus on passengers' perceptions. Because of the differences in each country, the LOS classification of the Transportation Research Board may not be applicable to all countries and situations. The study then analyses the research and practice of public transit LOS in China and suggests that the existing regulations in China can be improved to clearly define the connotation of public transit LOS and include a systematical classification standard that applicable to China. The challenges in improving the LOS are discussed from the aspects of the formation of LOS, the complexity of evaluation factors, multi-links involved in a trip, and the need for government support and investment. Based upon the practices inurban public transit in China, the following three topics are worthy of in-depth study in the future: define and evaluate public transit LOS in consideration of full travel chains; Measure and evaluate the public transit LOS considering the uneven distribution of transit service quality; Satisfaction survey methods focusing on passenger perception differentiation and LOS evaluation methods based on advanced information technology. The paper also provides suggestions on taking LOS improvement as a starting point to promote the enhancement of public transit operation quality and efficiency.