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81.
Assessing the cost of transfer inconvenience in public transport systems: A case study of the London Underground 总被引:2,自引:0,他引:2
Few studies have adequately assessed the cost of transfers2 in public transport systems, or provided useful guidance on transfer improvements, such as where to invest (which facility), how to invest (which aspect), and how much to invest (quantitative justification of the investment). This paper proposes a new method based on path choice,3 taking into account both the operator’s service supply and the customers’ subjective perceptions to assess transfer cost and to identify ways to reduce it. This method evaluates different transfer components (e.g., transfer walking, waiting, and penalty) with distinct policy solutions and differentiates between transfer stations and movements.The method is applied to one of the largest and most complex public transport systems in the world, the London Underground (LUL), with a focus on 17 major transfer stations and 303 transfer movements. This study confirms that transfers pose a significant cost to LUL, and that cost is distributed unevenly across stations and across platforms at a station. Transfer stations are perceived very differently by passengers in terms of their overall cost and composition. The case study suggests that a better understanding of transfer behavior and improvements to the transfer experience could significantly benefit public transport systems. 相似文献
82.
Sebastián Raveau Juan Carlos Muñoz 《Transportation Research Part A: Policy and Practice》2011,45(2):138-147
This article presents a route choice model for public transit networks that incorporates variables related to network topology, complementing those found in traditional models based on service levels (travel time, cost, transfers, etc.) and users’ socioeconomic and demographic characteristics (income level, trip purpose, etc.). The topological variables represent concepts such as the directness of the chosen route and user knowledge of the network. For both of these factors, the necessary data is endogenous to the modelling process and can be quantified without the need for information-gathering beyond what is normally required for building route choice models. Other novel variables in the proposed formulation capture notions of user comfort such as vehicle occupancy rates and certain physical characteristics of network stations. We conclude that these new variables significantly improve the explanatory and predictive ability of existing route choice specifications. 相似文献
83.
Modeling heterogeneous risk-taking behavior in route choice: A stochastic dominance approach 总被引:1,自引:0,他引:1
This paper proposes a unified approach to modeling heterogonous risk-taking behavior in route choice based on the theory of stochastic dominance (SD). Specifically, the first-, second-, and third-order stochastic dominance (FSD, SSD, TSD) are respectively linked to insatiability, risk-aversion and ruin-aversion within the framework of utility maximization. The paths that may be selected by travelers of different risk-taking preferences can be obtained from the corresponding SD-admissible paths, which can be generated using general dynamic programming. This paper also analyzes the relationship between the SD-based approach and other route choice models that consider risk-taking behavior. These route choice models employ a variety of reliability indexes, which often make the problem of finding optimal paths intractable. We show that the optimal paths with respect to these reliability indexes often belong to one of the three SD-admissible path sets. This finding offers not only an interpretation of risk-taking behavior consistent with the SD theory for these route choice models, but also a unified and computationally viable solution approach through SD-admissible path sets, which are usually small and can be generated without having to enumerate all paths. A generic label-correcting algorithm is proposed to generate FSD-, SSD-, and TSD-admissible paths, and numerical experiments are conducted to test the algorithm and to verify the analytical results. 相似文献
84.
基于广州居民出行调查成果,本文从模型架构、效用函数基本形式、参数标定及校核等几个方面对交通方式选择模型的构建进行研究. 提出了方式划分的基本原则,并针对无车家庭、有小汽车家庭和摩托车家庭构建层次划分. 以小汽车家庭为例,阐述方式划分的基本形式. 进而,提出了方式划分参数标定的方法和基本步骤以及系数校核的关键点. 最后将预测结果和实际观测数据进行比较,验证模型的有效性. 本文提出不同层次交通方式划分模型,提高了模型的精度,并在效用函数中引入收入、车辆拥有和吸引量等因素,增强了模型的适用性,为其他类似城市交通方式选择模型的构建提供一定的参考. 相似文献
85.
毛卫洪 《国防交通工程与技术》2011,9(5):15-17,4
我国山岭隧道的长度不断增加,数十公里的隧道不断投入到施工阶段,然而由于埋深大、施工支洞布置困难、环境保护要求高等因素影响,越来越多的硬岩掘进机(TBM)得以应用。TBM对地质条件的适应性不及钻爆法灵活,但适宜的地质条件下可以取得很高的施工进度,它可分为开敞式、单护盾、双护盾等不同类型。不同的TBM有不同的特点,不同的工... 相似文献
86.
87.
在考虑多源交通信息可能导致信息过剩,从而影响决策者出行选择的条件下,引入决策论的思想,通过对多源交通信息方式发布的特点分析,应用模糊物元理论,建立个体出行的行为选择模型,在熵值法确定客观权重的条件下,根据贴近度的大小对决策方案进行选择,克服出行者的主观经验判断。通过实例计算,证明了不确定型决策在多源交通信息影响下出行者路径选择方面的可用性,客观上能为其提供最优的出行路径。 相似文献
88.
在无信息、发布历史信息和发布预测信息3种信息条件下,分别建立了驾驶员的路径理解行程时间期望值的更新模型.通过建立一个含有2条平行路径的简单路网,对3种交通信息条件下驾驶员逐日路径选择进行了仿真,结果表明:交通信息对驾驶员的作用与驾驶员路径选择的随机程度和对信息依赖程度有关;在3种交通信息条件下,路网均不能达到用户均衡平衡状态;交通信息的预测方法不同,预测信息对驾驶员路径选择的影响有差异. 相似文献
89.
刘文歌 《交通运输系统工程与信息》2001,19(5):198-204
基于参数服从SB分布的混合Logit 模型进行道路交通统计生命价值的测算研究. 首先,结合意愿选择法和正交实验法设计出行路径选择调查问卷;然后,基于死亡风险系数服从对数正态分布和SB分布的混合Logit 模型,构建统计生命价值测算模型;接着以大连市私家车出行者为调查对象获得调查数据,并利用Monte Carlo 仿真方法进行模型参数标定;最后,对模型进行比较分析,并获得统计生命价值的测算值. 研究结果表明:死亡风险参数服从限制域为(0.0, 0.5)SB分布的混合Logit 模型,精确性更高且更合理;道路交通统计生命价值测算值为 105.76万元,这一结果可以作为道路交通安全项目经济评价的参考数据. 相似文献
90.
This paper presents an investigation of the temporal evolution of commuting mode choice preference structures. It contributes to two specific modelling issues: latent modal captivity and working with multiple repeated crossectional datasets. In this paper latent modal captivity refers to captive reliance on a specific mode rather than all feasible modes. Three household travel survey datasets collected in the Greater Toronto and Hamilton Area (GTHA) over a ten-year time period are used for empirical modelling. Datasets collected in different years are pooled and separate year-specific scale parameters and coefficients of key variables are estimated for different years. The empirical model clearly explains that there have been significant changes in latent modal captivity and the mode choice preference structures for commuting in the GTHA. Changes have occurred in the unexplained component of latent captivities, in transportation cost perceptions, and in the scales of commuting mode choice preferences. The empirical model also demonstrates that pooling multiple repeated cross-sectional datasets is an efficient way of capturing behavioural changes over time. Application of the proposed mode choice model for practical policy analysis and forecasting will ensure accurate forecasting and an enhanced understanding of policy impacts. 相似文献