Accessibility: an evaluation using consumer welfare

This study explores the worth consumers place on mode-destination accessibility for the AM journey to work trip. To accomplish this, a multinomial mode-destination choice model is estimated and the denominator of the specified logit model is used as an estimate of mode-destination accessibility. To improve the interpretability of this measure, compensating variation is then applied to convert the mode-destination accessibility to units of dollars per AM journey to work trip. The model is estimated using travel survey data from the Puget Sound Region in Washington state. It is reasonable to assume, for example, that the worth placed on mode-destination accessibility varies by mode, by destination, and by market segment (e.g., low income, high income). Less intuitive, however, are the magnitude and direction of these variations. This paper presents a methodological approach, followed by an empirical evaluation, for examining the worth of journey to work mode- destination accessibility. The results have important policy implications and also provide a mechanism for incorporating a monetary value for accessibility in future cost-benefit analyses.     

交通效率的度量方法研究

在全面分析交通效率内涵的基础上,提出了4种交通效率度量方法,即可达性、机动性、生产率、效用方法。分析了各种方法的优点与局限性。对珠江三角洲两个城市高速公路网络交通效率的验证分析表明这4种方法意义明确、算法简便。经进一步的理论分析,可以认为,这4种度量交通效率的方法将为规划工程师和决策人员提供直观、丰富而又简练的信息和决策帮助。     

An Evaluation of the Accessibility Benefits of Commuter Rail in Eastern Massachusetts using Spatial Hedonic Price Functions

We estimate spatial hedonic price functions to examine local and regional accessibility benefits of commuter rail service in Eastern Massachusetts, while controlling for proximity-related negative externalities and other confounding influences. The data include 1,860 single-family residential properties from four municipalities with commuter rail service, and three municipalities without commuter rail service. We find some evidence of the capitalization of accessibility to commuter rail stations. Two model specifications suggest that properties located in municipalities with commuter rail stations exhibit values that are between 9.6% and 10.1% higher than properties in municipalities without a commuter rail station. With a third model we detect weak evidence of the capitalization of auto access time or walking time to the stations, suggesting that properties located within a one-half mile buffer of a station have values that are 10.1% higher than properties located outside of this buffer area and that an additional minute of drive time from the station is related to a decrease of 1.6% in property values. Our results also indicate that proximity to commuter rail right-of-way has a significant negative effect on property values, which suggests that for every 1,000 ft. in distance from the commuter rail right-of-way, property values are between $732 and $2,897 higher, all else held equal. At the mean sample values, this result translates into an elasticity of between 0.03 and 0.13, depending on the functional form of the hedonic price equation.     

交通方式可达性差距——衡量交通可持续发展的指数

交通因其消耗大量能源而在可持续发展中扮演着重要角色,为了规划交通可持续发展,有必要提出能够评估和衡量交通可持续发展的指数。利用可达性概念和地理信息系统提出交通方式可达性差距指数。该指数由人口数量、就业岗位数、商店数以及学校数等决定,根据公共交通方式和私人交通方式间可达性指数差异计算。就能源效率而言,公共交通方式比私人交通方式更能实现可持续。可达性差距指数越高意味着可持续能力越强。通过比较香港1991年和1996年的可达性差距指数,来检验交通发展的可持续性是否有所提升。最后,讨论了如何运用可达性差距指数来检验土地利用以及交通发展政策和方案,以便确定更可持续的政策和方案。     

基于绕行系数的交通可达性研究

为了评价不同路网形态下的城市道路可达性和对出行者的出行方式选择的影响,通过引入绕行系数的概念,对不同路网密度和交通管理策略的案例研究,说明可达性的变化对交通方式选择的影响。提出了基于绕行系数的可达性分析的基本思路,研究结果表明：仅以出行距离作为交通方式选择的影响要素条件下,可达性的改善有利于非机动出行方式分担率提高,合理的城市路网密度和适当的交通管理策略有利于多种交通方式共同发展。     

空间阻隔视角下居住型地铁站步行可达性

居住型地铁站的步行可达性是影响地铁站使用率高低的主要因素。首先,调查研究此类站点附近居民的出行方式,分析影响天津市地铁2号线翠阜新村站可达性的空间阻隔因子。其次,从附近居民到达地铁站的时间、距离两方面对路网阻隔、土地利用阻隔、围墙阻隔、流线阻隔和天气阻隔等进行步行可达性分析。最后,运用空间阻隔模型,基于现状和改善措施后得到的量化对比结果,提出优化步行通道、增加站点出入口与周边居住区的连接度、加大站点周边街巷密度、拆除影响步行路线通行的障碍物等优化策略。以期对今后居住型地铁站步行可达性的改善提供具体措施和改进建议。     

空间可达性研究综述

可达性概念在理解上的分歧产生了许多本质认识及测算方法上的混乱,为了全面、准确地理解可达性,运用文献综述的方法,全面回顾国内外学者对其本质含义及测算方法的论述。对空间可达性的认识及测算方法总体上分为三种类型：空间阻隔、机会累积和空间相互作用。基于空间阻隔的方法是从纯形态学角度来分析可达性,而基于机会累积和基于空间相互作用的方法还考察土地使用和发展机会对可达性的影响。基于机会累积的测算方法强调某点在等时线范围内所能接触到的机会累积量,而基于空间相互作用的测算方法侧重于出发点与目的点间的相互作用强度。与机动性概念相比,可达性在城市研究和交通规划中有着更为广泛且重要的应用：首先,能夯实城市交通规划的指导原则;其次,能准确监测与评价交通项目实施效果;最后,能深刻诠释城市空间结构。     

A GIS-based planning approach to locating urban rail terminals

This paper develops a flexible GIS-based methodology for evaluating the potential locations of terminal park-and-ride facilities along urban rail lines. The methodology differs from political-based approaches and traditional travel demand modeling in its use of an objective measure of accessibility to gage the suitability of a site. The methodology begins by constructing an index of derived demand for rail usage based on the local demographics. Principal component analysis (PCA) is used as a means of constructing an index of derived demand consistent with other passenger surveys. Next, trade areas or commutersheds are calculated for each candidate park-and-ride location based on realistic measures of accessibility and network based drive times, taking into account competition among candidates for riders. Following the analysis, the candidate locations and their commutersheds are delineated and visualized in the GIS environment. In summary, application of this method produces a site-specific suitability index that may be used to rank and compare potential park-and-ride locations. We illustrate how our approach fits within the context of the larger-scale corridor study as a complimentary means of refining the location of urban rail stations. The analysis uses the proposed rail system for Columbus Ohio as a case study. This revised version was published online in June 2006 with corrections to the Cover Date.     

可达性在城市群交通规划中的应用研究

在城市群交通规划中,“四阶段”模型存在一定缺陷,它不能准确地反映城市发展过程中城市之间的联系程度和交通需求强度。将可达性贯穿于城市群交通规划中的基于节点重要度的城市群可达性计算新方法,能比较准确地反映不同阶段城市群内部之间的联系程度．为交通规划提供了一定的参考。     

南京中心市区居住用地水系可达性分析

为探讨水系可达性对城市居住用地分布的影响,基于交通可达性的概念和最短路径分析法,在GIS平台上构建了城市居住用地水系可达性模型.借助ArcGIS9.2软件,计算了不同交通等级的最小时间成本,分析了南京中心市区1990年和2008年居住用地的水系可达性时距圈和新增居住用地分布的变化特征.研究表明:从1990年到2008年,南京中心市区水系可达性在5 min以内的居住用地的比例约降10%,在5～10 min之间的增加5.8%,在10～20 min之间的增加5.4,在20～30 min之问的没有明显变化;约80%的新增居住用地分布在10 min水系可达范围内,说明近20 a来,南京中心市区近距离水系可达性居住用地的比例呈下降趋势,但新增居住用地具有明显的亲水性特征.