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1.
There is a significant body of evidence from both disaggregate choice modelling literature and practical travel demand forecasting that the responsiveness to cost and possibly to time diminishes with journey length. This has, in Britain at least, been termed ‘Cost Damping’, and is recognised in guidance issued by the UK Department for Transport. However, the consistency of the effect across modes and data types has not been established. Cost damping, if it exists, affects both the forecasting of demand and our understanding of behaviour. This paper aims to investigate the evidence for cost and time damping in rail demand using aggregate rail ticket sales data. The rail ticket sales data in Britain has, for many years, formed the basis of analysis of a wide range of impacts of rail demand. It records the number of tickets sold between station pairs, and it is generally felt to provide a reasonably accurate reflection of travel demand. However, the consistency of these direct demand models with choice modelling and highway demand model structures has not been investigated. Rail direct demand models estimated by ticket sales data indicate only slight variation in the fare elasticity with distance, as is evidenced in the largest meta-analysis of price elasticities conducted to date (Wardman in J Transp Econ Policy 48(3):367–384, 2014). This study of UK elasticities shows strong variation between urban and inter-urban trips, presumably a segmentation at least in part by purpose, but less remaining variation by trip length. A lack of variation by length supports the hypothesis of cost damping, because constant cost sensitivity would imply that fare elasticity would increase strongly with distance, because of the increasing impact of higher fares at longer distances. In this paper we indicate that rail direct demand models have some consistency of behavioural paradigm with utility based choice models used in highway planning. We go on to use rail demand data to estimate time and fare elasticities in the context of various cost damping functions. Our empirical contribution is to estimate time elasticities on a basis directly comparable with cost elasticities and to show that the phenomenon of cost damping is strongly present in ticket sales data. This finding implies that cost damping should be included in models intended for multimodal analysis, which may otherwise give incorrect predictions. 相似文献
2.
M. R. Wigan 《Transportation》1987,14(4):395-417
Transport, communications and urban form cover an overlapping area of rising academic and practical concern. This paper traces several of the many themes brought together under different professional banners, and shows how a confluence of interest is emerging.The themes are the developments in urban planning analysis, transport and time use studies, telecommunications and industrial location, all of which contribute to the area of locational effects of improved telecommunications technology, and are affected by alterations in the nature of work and the uses made of time by individuals. The convergence of geographical, planning, transportation and communication developments now requires explicit investigation, as the timings of technological and theoretical developments appear to coincide with the emergence of a significant need to do so. Some of the gaps between present knowledge and expertise that need to be filled are specified.These include the investigation of the testing and use of current land use integrated analyses for road and development assessment, investigation of the nature and characteristics of work and education which are most affected by telecommunications and computer support, development of longitudinal monitoring methods for overall urban development leading indicators, exploitation of newly-available cross-sectional household and city data sets in conjunction with historical data for longitudinal investigations and forward projections, accounting for altered family structure and activity patterns and the anticipation and assessment of probable further technological change, which can and will undermine many current long term commitments. 相似文献
3.
The past decade has seen many new freight transport models for use in transport planning by public authorities. Some of these models have developed new concepts, such as logistics modules, inclusion of transshipments, storage and sourcing and the determination of shipment size. This paper provides a review of the European literature on freight transport models that operate at the national or international level and have been developed since 2004. The introduction of elements of logistics thinking is identified as a common theme in recently developed models, and further worked out. Furthermore, ideas on what might be the next key developments in freight transport modelling are presented. 相似文献
4.
Simplified transport models based on traffic counts 总被引:4,自引:0,他引:4
L. G. Willumsen 《Transportation》1981,10(3):257-278
Having accepted the need for the development of simpler and less cumbersome transport demand models, the paper concentrates on one possible line for simplification: estimation of trip matrices from link volume counts. Traffic counts are particularly attractive as a data basis for modelling because of their availability, low cost and nondisruptive character. It is first established that in normal conditions it may be possible to find more than one trip matrix which, when loaded onto a network, reproduces the observed link volumes. The paper then identifies three approaches to reduce this underspecification problem and produce a unique trip matrix consistent with the counts. The first approach consists of assuming that trip-making behaviour can be explained by a gravity model whose parameters can be calibrated from the traffic counts. Several forms of this gravity model have been put forward and they are discussed in Section 3. The second approach uses mathematical programming techniques associated to equilibrium assignment problems to estimate a trip matrix in congested areas. This method can also be supplemented by a special distribution model developed for small areas. The third approach relies on entropy and information theory considerations to estimate the most likely trip matrix consistent with the observed flows. A particular feature of this group is that they can include prior, perhaps outdated, information about the matrix.These three approaches are then compared and their likely areas for application identified. Problems for further research are discussed and finally an assessment is made of the possible role of these models vis-a-vis recent developments in transport planning. 相似文献
5.
Maria Börjesson 《Transportation》2014,41(2):377-396
The parameters for travel time and travel cost are central in travel demand forecasting models. Since valuation of infrastructure investments requires prediction of travel demand for future evaluation years, inter-temporal variation of the travel time and travel cost parameters is a key issue in forecasting. Using two identical stated choice experiments conducted among Swedish drivers with an interval of 13 years, 1994 and 2007, this paper estimates the inter-temporal variation in travel time and cost parameters (under the assumption that the variance of the error components of the indirect utility function is equal across the two datasets). It is found that the travel time parameter has remained constant over time but that the travel cost parameter has declined in real terms. The trend decline in the cost parameter can be entirely explained by higher average income level in the 2007 sample compared to the 1994 sample. The results support the recommendation to keep the travel time parameter constant over time in forecast models, but to deflate the travel cost parameter with the forecasted income increase among travellers and the relevant income elasticity of the cost parameter. Evidence from this study further suggests that the inter-temporal and the cross-sectional income elasticities of the cost parameter are equal. The average elasticity is found to be ?0.8 to ?0.9 in the present sample of drivers, and the elasticity is found to increase with the real income level, both in the cross-section and over time. 相似文献
6.
A wide range of transport‐related decisions involve the linking of discrete choices (e.g. of vehicle choice) and continuous choices (e.g. of vehicle use). In recent years econometricians have developed procedures for integrating such choices into a framework that is both economically and statistically sound. The literature is however somewhat technical. The objective of this paper is to provide a general overview of the basic elements of discrete/continuous econometric modelling with an emphasis on transport applications. It is hoped that such an introduction will demonstrate that the essence of the approach for the practitioner is quite straightforward and can be implemented with widely available computer software. 相似文献
7.
Martin Wachs 《Transportation》1993,20(4):329-354
Los Angeles is well known around the world as an automobile-oriented low density community, yet recent transportation policies have emphasized greater capital investment in rail transportation than in highways, and recent policies have attempted to discourage automobile usage through transportation demand management. While these policies have accomplished small shifts toward public transport and somewhat lower dependence upon singly occupied automobilies for work commuting, the financial costs of these policy changes has been very large in relation to their benefits. Proper pricing of transportation alternatives, more creative use of new and emerging transportation technologies, and the provision of many more opportunities for simpler private sector transport services, would all appear to be more promising as cost-effective approaches to coping with congestion in Los Angeles than the current regional transportation policies. 相似文献
8.
Christian Lardinois 《运输评论》2013,33(2):119-143
This paper presents a review of supply models in the field of intercity passenger transport, together with an attempt to characterize these models with regard to normative and predictive approaches, and in relation to the full hierarchy of strategic, tactical and operational decision‐making situations. Part of the paper deals with computerized decision support systems. Major research directions are presented and the main opportunities for further research are identified. 相似文献
9.
Transportation - Traditionally, transport planning model systems are estimated and calibrated in an unstructured way, which does not allow for interactions among included parameters to be... 相似文献
10.
Konstantinos G. Zografos Konstantinos N. Androutsopoulos Teemu Sihvola 《Transportation》2008,35(6):777-795
Flexible transport services include a wide range of demand responsive transport systems that provide non-conventional passenger
and freight transportation services. Several alternative business models varying according to the local market conditions,
the socio-economic, legal, and institutional framework may be developed for the provision of Flexible Transport Systems (FTS).
The objective of this paper is twofold: first to present an integrated methodological framework for developing and assessing
alternative FTS business models and second to demonstrate its applicability to a case study regarding the prioritization of
alternative FTS business models for the provision of flexible passenger transport services in Helsinki.
相似文献
Teemu SihvolaEmail: |
11.
A new model system dealing with trips of length up to 100 km has recently been developed in Norway. A new way of dealing with
seasonal passes for public transport is used in the travel-to-work model. The objective was to account for the fact that a
respondent that posses a seasonal pass for public transport may behave as if public transport is free on the day they report
a travel diary. On the other hand, we can not assume that public transport is free for respondents that used other modes of
transport or that public transport is free to alternative destinations. This problem was solved by defining seasonal pass
as a separate alternative in the form of a nest that included all modes of travel. The cost of a seasonal pass is a common
cost for all modes in the nest and will thus not affect the choice within the nest. The estimation of this specification is
compared with the more common approach of assigning an average cost per day based on the cost of a monthly pass and the number
of workdays in a month. The comparison indicates that the “average cost per day” approach may produce biased estimates for
several parameters. It also turns out that the cost parameter for seasonal pass is higher than the parameter for “out of pocket”
cost, probably reflecting that there will be some uncertainty with respect to the actual use of a seasonal pass. 相似文献
12.
Peter Bonsall 《Transportation》1976,5(3):309-329
This paper highlights some of the difficulties involved in the implementation of complex cost structures in the tree-building section of a transport demand model. The conventional tree-building algorithm is briefly described and is seen to be inadequate for the present purpose. A new algorithm is then presented which is able to implement complex cost structures properly. An example is given of the application of this algorithm to the building of tree in a public transport network. The performance of a computer program incorporating the new alrogrithm is evaluated against alternative methods of implementing complex cost structures. Some mention is then made of the vast range of potential uses for the new algorithm in the field of transport modelling and simulation. 相似文献
13.
文章以施工项目的成本管理工作为主线,阐述了加强成本管理对企业实施低成本战略的意义和必要性,分析了实施项目成本管理中存在的问题,重点论述了项目成本管理过程中需要采取的各种成本控制措施。 相似文献
14.
Foreign consultants still provide much of the analytical expertise for transport planning studies conducted in the Gulf States and other rapidly developing countries. Most of the systems analysis techniques used are adaptations of those developed for western urban areas. The populations of the Gulf States are unique in that they contain very large populations of foreign workers who have very different social and economic characteristics from the national populations. This paper describes these differences and shows how they have influenced the spatial evolution of the Kuwait metropolitan area and the associated transport demands. The paper also describes the analytical tools that are most appropriate for capturing the transport behaviour of residents of the Kuwait metropolitan area. 相似文献
15.
Els Beukers Luca BertoliniMarco Te Brömmelstroet 《Transportation Research Part A: Policy and Practice》2012,46(1):68-78
Academic discussions on Cost Benefit Analysis (CBA) as an appraisal instrument for integrated land use and transportation plans tend to focus on its technical aspects. However, many issues of CBA also arise from process related matters, especially when assessing integrated plans. Using an inductive research design, we explored how these process related issues play out in Dutch planning practices. In two applied research techniques, focus group sessions and open in depth interviews, we focused on process related issues as perceived by CBA participants ranging from plan makers to CBA testers. This article presents the different perceptions of issues in CBA processes. Through these collected perspectives, we found that these issues are multi-layered and present a number of fundamental dilemmas. After relating our empirical data to theory, we conclude that the biggest challenge lies in decreasing the level of mistrust and communication deficits revealed between plan owners and CBA calculators and their respective frames of thinking when assessing complex integrated land use and transportation plans. 相似文献
16.
《Transportation Research Part A: Policy and Practice》2007,41(5):428-443
This paper uses state of the art stated choice designs to parameterise modal choice models for commuting and non-commuting travel futures in the presence of new public transport infrastructure (variations of new heavy rail, light rail and dedicated busway systems). D-optimal choice experiments are developed for a set of labelled modal alternatives in which respondents establish a reference benchmark based on the existing service levels (for access, linehaul and egress trip legs) which is used in a computer aided personal interview instrument to generate future scenarios of service levels for current and prospective new modals options. We show that a fully integrated stated choice experiment provides all the information required to obtain behaviourally relevant parameter estimates (within a nested logit framework) for all but the mode-specific constants (MSCs). The MSCs can be calibrated for the current modes within a network model setting, giving the transport planner an appropriate model for predicting the patronage potential for proposed new public transport infrastructure services. A useful by-product is a new set of behavioural values of travel time savings for access, egress, linehaul and wait times. 相似文献
17.
无论是城市公共客运、城市出租客运、旅游客运,它都具备了道路旅客运输的基本特点、基本属性,人为地将这一市场割裂,说明现行政策离"群众满意"这个根本出发点还有一定的距离. 相似文献
18.
Pierre Merlin 《运输规划与技术》2013,36(1):39-52
A decade of increasing Federal attention to urban transportation needs has culminated in the 1970 Urban Mass Transportation Assistance Act. This Act is intended to provide 10 thousand million dollars over the next 12 years in Federal assistance money to urban public transportation systems. This paper examines the needs of selected U.S. cities as a basis for (1) understanding the vast, various and complex transportation needs of urban areas throughout the country, and (2) assessing the sufficiency of these funds. The sample cities have been placed into three broad categories based on the state of development of their transportation systems. In Category I cities, the essential need is to ensure the survival of bus systems for the use of non‐drivers, or to provide some other viable alternative to the automobile; in Category II cities, the primary needs are to relieve auto congestion and to improve public transportation components, while in Category III cities, the primary need is massive investment to improve and to extend public transportation facilities. It is concluded that the presently intended Federal funding level for transportation will not meet the financial requirements of the Category III cities. 相似文献
19.
G. Čelechovský 《Transportation》1972,1(2):151-176
Etarea is a planned satellite town for Prague, the capital of Czechoslovakia, located some 10 km from the outskirts of the capital. Its projected population of 135,000 will live in 13 residential areas, each of which will have its own retail centre in addition to the main retail centre.The plans for Etarea incorporate a unique approach to the related problems of the storage and distribution of goods within urban areas. All incoming goods will be delivered by road or rail, and possibly in the future by water, to a central storage complex. Goods for the retail trade are distributed from this central store by automated trains pulled by battery-powered trucks, each train having a capacity of 8.75 tons. The trains, which run in a network of underground tunnels, 2 \sX 2.5 meters in cross section, are guided by an optical sensing system. The underground network comprises 3 main routes with branches serving the individual centres. Secondary storage facilities are planned for each of the 14 retail centres where unit loads received from the main storage centre are subdivided for retail sale.One of the proposed methods of retail distribution provides for the fully automated delivery of goods from the retail centres direct to the consumer's household. This is accomplished by means of a pneumatic tube system similar to that used for handling cash in some large stores. Orders will be placed by dialling the code number assigned to the required item, given in a catalogue of available goods. Provided that the customer's account is in credit the order will be accepted and the goods automatically dispatched from the local centre; delivery is estimated to take between 2.5 and 11.5 minutes depending on the distance of the customer's house from the centre. The same system is utilised for the delivery of regular orders for such items as newspapers and magazines as well as for mail and for the the removal of household refuse. In addition to the automated system each retail centre will also have over-the-counter, self-service and slot machine facilities for the sale of goods.All proposals for goods storage and distribution planned for Etarea are based on existing technologies. 相似文献
20.