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991.
Role of the built environment on mode choice decisions: additional evidence on the impact of density 总被引:5,自引:2,他引:3
Density is a key component in the recent surge of mixed-use neighborhood developments. Empirical research has shown an inconsistent
picture on the impact of density. In particular, it is unclear whether it is the density or the variables that go long with
density that affect people’s travel behavior. Many existing studies on density neglect confounding factors, for example, residential
self-selection, generalized travel cost, accessibility, and access to transit stations. In addition, most still use a single
trip as their observation unit, even though trip chaining is well recognized. The goal of this paper is to assess the role
of density in affecting mode choice decisions in home-based work tours, while controlling for confounding factors. Using the
dataset collected in the New York Metropolitan Region, we estimated a simultaneous two-equation system comprising two mutually
interacting dependent variables: car ownership and the propensity to use auto. The results confirm the role of density after
controlling for the confounding factors; in particular, employment density at work exerts more influence than residential
density at home. The study also demonstrates the importance of using tour as the analysis unit in mode choice decisions. The
study advances the field by analyzing the role of the built environment on home-based work tours. New knowledge is obtained
in the relative contribution of density vs. a set of correlated factors, including generalized travel cost, accessibility,
and access to transit stations.
Cynthia Chen is an Assistant Professor in Civil Engineering at City College of New York. Her research expertise and interests are residential location and activity and travel choices and human’s interaction with the environment. Hongmian Gong is an Associate Professor in Geography at Hunter College of the City University of New York. Her research interests are urban geography, urban transportation, and urban GIS. Robert Paaswell is currently Distinguished Professor of Civil Engineering and Director of the University Transportation Research Center at the City College of New York. He currently serves on several NY MTA Commissions. 相似文献
Robert PaaswellEmail: |
Cynthia Chen is an Assistant Professor in Civil Engineering at City College of New York. Her research expertise and interests are residential location and activity and travel choices and human’s interaction with the environment. Hongmian Gong is an Associate Professor in Geography at Hunter College of the City University of New York. Her research interests are urban geography, urban transportation, and urban GIS. Robert Paaswell is currently Distinguished Professor of Civil Engineering and Director of the University Transportation Research Center at the City College of New York. He currently serves on several NY MTA Commissions. 相似文献
992.
基于灰靶理论的隧道路面结构类型选择 总被引:1,自引:1,他引:0
为了选择适合于隧道工作环境与交通条件的路面结构类型,提高隧道路面的使用性能延长使用寿命,在广泛调研的基础上,采用灰靶理论从整体刚度、耐久性、平整度、抗滑性能、耐磨性能、修复与重建难度6个方面系统地比较了水泥混凝土与沥青混凝土两种常用的路面结构类型在隧道内的适用性。分析结果表明,采用灰靶理论评判模型选择隧道路面结构类型在一定程度上克服了选择过程的主观因素,使隧道路面的选择结果更具有客观性;在隧道内特殊的工作环境与交通条件下沥青路面的性能更加优越,具有更好的适用性,能提高隧道路面抗滑性能,降低噪音,改善行车舒适性,维修、养护简便,保证隧道营运通畅,为实体工程路面结构类型选择提供依据。 相似文献
993.
Suppose that in an urban transportation network there is a specific advanced traveler information system (ATIS) which acts for reducing the drivers' travel time uncertainty through provision of pre‐trip route information. Because of the imperfect information provided, some travelers are not in compliance with the ATIS advice although equipped with the device. We thus divide all travelers into three groups, one group unequipped with ATIS, another group equipped and in compliance with ATIS advice and the third group equipped but without compliance with the advice. Each traveler makes route choice in a logit‐based manner and a stochastic user equilibrium with multiple user classes is reached for every day. In this paper, we propose a model to investigate the evolutions of daily path travel time, daily ATIS compliance rate and yearly ATIS adoption, in which the equilibrium for every day's route choice is kept. The stability of the evolution model is initially analyzed. Numerical results obtained from a test network are presented for demonstrating the model's ability in depicting the day‐to‐day and year‐to‐year evolutions. 相似文献
994.
This paper develops a new method to solve multivariate discrete–continuous problems and applies the model to measure the influence of residential density on households’ vehicle fuel efficiency and usage choices. Traditional discrete–continuous modelling of vehicle holding choice and vehicle usage becomes unwieldy with large numbers of vehicles and vehicle categories. I propose a more flexible method of modelling vehicle holdings in terms of number of vehicles in each category, using a Bayesian multivariate ordinal response system. I also combine the multivariate ordered equations with Tobit equations to jointly estimate vehicle type/usage demand in a reduced form, offering a simpler alternative to the traditional discrete/continuous analysis. Using the 2001 National Household Travel Survey data, I find that increasing residential density reduces households’ truck holdings and utilization in a statistically significant but economically insignificant way. The results are broadly consistent with those from a model derived from random utility maximization. The method developed above can be applied to other discrete–continuous problems. 相似文献
995.
北京市现行的老年人公交免费政策在保障老年人日常出行的同时,诱发了老年人无谓出行、高峰出行、冒乘出行等问题. 针对不同出行目的、出行距离及出发时刻下老年人出行行为偏好,基于北京市第五次综合交通调查数据,构建多场景下老年人出行方式选择MNL (Multinominal Logit)模型,分析错峰优惠、阶梯式津贴等补贴政策对多方式分担率的影响,并从公共交通运能利用率、政府补贴和老年人公交支出等方面评价政策效果. 结果表明:相对现行政策,两种政策均可有效调节老年人出行行为,前者能够缓解政府财政补贴压力,但造成老年人公交支出的上升;后者侧重保护老年人群的社会福利,对行为的引导效果更显著,但仍需大量的财政补贴投入. 相似文献
996.
Inconsistent choices in Stated Choice data;Use of the logit scaling approach to handle resulting variance increases 总被引:2,自引:0,他引:2
The scaling approach is a statistical estimation method that allows for differences in the amount of unexplained variation in different types of data, which can then be used together in the analysis. This approach has been mostly used in context of combining Stated Preference and Revealed Preference data, but has also been used as a method of identifying systematic differences in the variance of choices within a single Stated Preference data set, e.g. for investigation of learning and fatigue effects. This paper investigates whether a scaling approach is suitable for handling inconsistencies in Stated Choice data. Both the number of inconsistent choices, based on a test of violations of the transitivity axiom, and education are used as scaling variables. Scaling effects appear to exist due to inconsistent choices, and the amount of unexplained variance is shown to increase as the number of inconsistent choice increase. Scaling due to inconsistencies significantly improves the models and reduces the valuations of travel time. In addition, the scaling approach makes the valuations of travel time from the Stated Choice data more consistent with the valuations from Contingent Valuation data included in the same study. In spite of the fact that education is the only significant explanatory variable for the number of inconsistent choices, scaling due to education gives no significant improvement in the model. 相似文献
997.
国外城市轨道交通经济研究简要回顾 总被引:1,自引:0,他引:1
面对中国城市轨道交通快速发展的现状,指出有必要重视城市轨道交通经济的实证研究,探索轨道交通市场的特征以及经济规律。简要回顾了发达国家尤其是美国城市轨道交通的兴衰,探讨了交通经济经典著作《城市交通问题》的主要观点、离散选择模型在城市轨道交通规划中的应用及其重要参数的经济含义。最后,追溯了发展中国家城市轨道交通发展中面临的财务问题以及私营部门参与的经验。 相似文献
998.
999.
农村公路管理养护体制改革的思路 总被引:1,自引:0,他引:1
根据我市农村公路养护体制改革的现状,结合实际,提出对农村公路管理养护体制改革的的几点思路. 相似文献
1000.