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1.
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A preliminary theoretical model is developed for the mechanism of behavioural adaptations to changes in the road transport system, which describes the process of behavioural change, explains the nature of adaptation phenomenon, and predicts its effects on road safety programmes. It can be used as a basis to organize the body of adaptation research and to explain empirical results.  相似文献   

3.
This paper examines transport policy development in a regional grouping of states whose present transport policies reflect their differing colonial pasts. In addition to locational and physical factors, vested interests in preserving present arrangements, lack of assessment of the repercussions of integration, and lack of political will to surrender to a supra‐national authority decisions which will be binding at the national level are identified as major factors militating against the successful formulation of a common transport policy in West Africa.

It is suggested that, although major changes of policy are often difficult and costly to implement, there is the need to effect institutional changes within the subregion in order to achieve the transport objectives of the ECOWAS treaty.  相似文献   

4.
This paper describes a logit model of route choice for urban public transport and explains how the archived data from a smart card-based fare payment system can be used for the choice set generation and model estimation. It demonstrates the feasibility and simplicity of applying a trip-chaining method to infer passenger journeys from smart card transactions data. Not only origins and destinations of passenger journeys can be inferred but also the interchanges between the segments of a linked journey can be recognised. The attributes of the corresponding routes, such as in-vehicle travel time, transfer walking time and to get from alighting stop to trip destination, the need to change, and the time headway of the first transportation line, can be determined by the combination of smart card data with other data sources, such as a street map and timetable. The smart card data represent a large volume of revealed preference data that allows travellers' behaviour to be modelled with higher accuracy than by using traditional survey data. A multinomial route choice model is proposed and estimated by the maximum likelihood method, using urban public transport in ?ilina, the Slovak Republic, as a case study  相似文献   

5.
Accessibility is a valuable indicator for assessing the effectiveness of a transport network. Nevertheless, its analysis can lead to very heterogeneous results depending on the method adopted, thus still struggling to be considered by policy makers and in planning processes. This article contributes to the development of an accessibility analysis as a planning tool, by proposing an alternative model to estimate the relative accessibility of a destination by public transport (PT). Indeed, PT is a mobility paradigm that has been supported to reduce the negative externalities produced by private transport, especially in environmentally fragile contexts. The model includes a set of eleven factors affecting public transport operation which refer to four macro topics: connectivity, multimodality, tariff/ticketing, and info-mobility. They are integrated into a Public Transport Accessibility index which analyses a series of nodes along a route and detects the progressive variation of accessibility. Eventual shifts are highlighted, including information about the factors feeding them. The model is tested for the Lana-Zurich (IT-CH) connection, showing how the most relevant issues are caused by difficulties in the transnational and transregional integration of the services. Through this process, the model aims at backing policy makers in the detection and understanding of public transport barriers and related causes.  相似文献   

6.
This paper provides a unifying framework for micro-based models of freight transport demand. An expected utility of profits model is posed that clarifies the conditions under which a system of equations (continuous) regression model should be used as opposed to the conditions that make a quantal choice model appropriate. The model also indicates the nature of subjective data that is necessary for estimating demand. In general, the conditions that give rise to the appropriate use of a quantal choice model imply that the needed subjective information is completely contained in the subjective probability distributions on the service characteristics; the utility function itself is irrelevant.  相似文献   

7.
《Transportation》1981,10(3):299-303
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8.
Transport authorities, especially those in developing countries where rising income stimulate increased car ownership rates, are often concerned with maintaining or increasing levels of public transport use. Therefore, the ability to identify clients at risk of abandoning the system can be valuable for remedial measures, allowing for more focused quality improvements. We present and apply a model that determines the probability of migrating from public to private transport at both aggregated and disaggregated levels. In application, the model predicted migration with 60% accuracy in the first preference recovery measure. The proposed model can improve the understanding of the behavior of public transport users, the analysis of demand stability and the factors influencing migration. This, in turn, can help to focus policy and management measures and increase the efficiency of public investment.  相似文献   

9.
Abstract

The concepts of optimal strategy and hyperpath were born within the framework of static frequency-based public transport assignment, where it is assumed that travel times and frequencies do not change over time and no overcrowding occurs. However, the formation of queues at public transport stops can prevent passengers from boarding the first vehicle approaching and can thus lead to additional delays in their trip. Assuming that passengers know from previous experience that for certain stops/lines they will have to wait for the arrival of the 2nd, 3rd, …, k-th vehicle, they may alter their route choices, thus resulting in a different assignment of flows across the network. The aim of this paper is to investigate route choice behaviour changes as a result of the formation and dispersion of queues at stops within the framework of optimal travel strategies. A new model is developed, based on modifications of existing algorithms.  相似文献   

10.
The effects of high passenger density at bus stops, at rail stations, inside buses and trains are diverse. This paper examines the multiple dimensions of passenger crowding related to public transport demand, supply and operations, including effects on operating speed, waiting time, travel time reliability, passengers’ wellbeing, valuation of waiting and in-vehicle time savings, route and bus choice, and optimal levels of frequency, vehicle size and fare. Secondly, crowding externalities are estimated for rail and bus services in Sydney, in order to show the impact of crowding on the estimated value of in-vehicle time savings and demand prediction. Using Multinomial Logit (MNL) and Error Components (EC) models, we show that alternative assumptions concerning the threshold load factor that triggers a crowding externality effect do have an influence on the value of travel time (VTTS) for low occupancy levels (all passengers sitting); however, for high occupancy levels, alternative crowding models estimate similar VTTS. Importantly, if demand for a public transport service is estimated without explicit consideration of crowding as a source of disutility for passengers, demand will be overestimated if the service is designed to have a number of standees beyond a threshold, as analytically shown using a MNL choice model. More research is needed to explore if these findings hold with more complex choice models and in other contexts.  相似文献   

11.
As urban areas face increasing demands for new transport infrastructure to promote a sustainable future with an increasing reality of constrained government budgets, the debate on whether we should focus on rail or bus-based investments continues unabated in many jurisdictions. Associated with the debate is an emotional (or ideological) bias by communities in favour of one mode, especially rail, which carries much sway at the political level as if there is no budget constraint. This paper presents a stated choice experiment to investigate this context as two unlabelled options described by 20 potential drivers of community preferences for improved public transport, where each choice scenario is conditioned on an estimated construction cost and a total annual transport infrastructure budget for the relevant geographical jurisdiction. This is followed by a labelling of each alternative to reveal whether the option is bus rapid transit (BRT) or light rail (LRT) and to establish whether this additional information influences preference revision. Data is collected in all eight capital cities of Australia in mid 2014. Mixed logit models with heteroscedastic conditioning in terms of the cost of the project infrastructure and whether the alternative is labelled BRT or LRT, provide new evidence on the nature and extent of community modal bias in a budget-constrained choice setting. The conclusions are twofold. On the one hand, if a fully compensatory choice rule is assumed (as is common in all previous modal comparison studies), LRT is predominantly preferred over BRT despite budgetary constraints, similarities in quality of service attributes and the opportunity to choose a greater network coverage for a given construction cost. However, when we allow for attribute non-attendance (a semi-compensatory choice rule), the modal bias is no longer a significant driver of preferences.  相似文献   

12.
Abstract

This two‐part article, concerned with the way public transport ridership is affected by the various relevant factors, is based on the Executive Summary of The Demand for Public Transport (Webster and Bly 1980), the report of the TRRL‐sponsored International Collaborative Study on Factors Affecting Public Transport Patronage. Part I of the article, which was concerned with the social and economic conditions in which public transport operates, showed the importance of the background factors such as income, car ownership and land use on public transport usage: it also indicated how the longer‐term impacts of the more direct demand factors (fares, service levels) often show themselves in changes in car ownership levels, activity patterns (i.e. where people live, work, shop, socialize, etc) and land‐use development.

Part II reviews the current state of knowledge on the effects of changes in fare levels and quality of service and of the introduction of various traffic and transport measures (traffic restraint, bus priority, etc): it outlines current methodology on costing public transport services and draws the supply and demand sides together in a consideration of particular strategies which are at the disposal of the operator, the planner and the policy maker.  相似文献   

13.
This article presents a new approach to microscopic road traffic exhaust emission modelling. The model described uses data from the SCOOT demand-responsive traffic control system implemented in over 170 cities across the world. Estimates of vehicle speed and classification are made using data from inductive detector loops located on every SCOOT link. This data feeds into a microscopic traffic model to enable enhanced modelling of the driving modes of vehicles (acceleration, deceleration, idling and cruising). Estimates of carbon monoxide emissions are made by applying emission factors from an extensive literature review. A critical appraisal of the development and validation of the model is given before the model is applied to a study of the impact of high emitting vehicles. The article concludes with a discussion of the requirements for the future development and benefits of the application of such a model.  相似文献   

14.
随着2008年奥运会的临近,走过百年历程的天津公交,迫切感受到提升公交质量的必要。作为奥运协办城市,该市提升公交车档次的计划已经纳入议事日程,快速公交1路的开通就是一个重要标志,而中通客车无疑是首轮竞标的最大赢家。  相似文献   

15.
Rietveld  Piet  Roson  Roberto 《Transportation》2002,29(4):397-417
Markets for transport are often characterised by unequal demand in both directions: every morning during peak hours the trains are crowded while moving towards the direction of large cities, whereas they may be almost empty in the other direction. In this paper we discuss the implications of these imbalances for price setting of transport firms. From the viewpoint of economic theory, two regimes can be distinguished: one where – owing to price discrimination – the flows are equal, and one where unequal flows are the result. Special attention is paid to the case where the transport firm does not apply price discrimination, as is the case with most railway firms in Europe. We find that in the case of substantial joint costs, the introduction of price discrimination not only leads to an increase of profits, but also to positive effects on consumer surplus. This result differs from the standard result in the literature on industrial economics. The standard result purports that with linear demand functions price discrimination has a negative impact on the welfare of the average consumer and that this negative impact dominates the positive effect on profits of the producer.  相似文献   

16.
The present study uses meta-regression in order to explain the wide variation in elasticity estimates obtained in previous demand studies, and provide summaries of several bus demand elasticities.One important finding as to the price elasticity is that the often cited rule of thumb of −0.3 holds good if quality of service represented by vehicle-kilometres is treated as an exogenous variable, but not when it is treated as endogenous.Based on the results it is recommended that demand models should include car ownership, price of petrol, own price, income and some measure of service among the explanatory variables and that the service variable should be treated as endogenous.In previous meta-studies in this field focus has been on own price elasticity only while this study also includes elasticities with respect to, level of service, income, price of petrol and car ownership. The short run for the US are found to be −0.59, 1.05, −0.62, 0.4 and −1.48 respectively.  相似文献   

17.
无论是发达国家,还是发展中国家,城乡公共汽车,火车和地铁等群体性公共交通行业大多是亏本的买卖,以前我对此不相信,自从我担任一家远洋运输公司的商务监督,跑遍全球38个国家和地区的城市,亲眼目睹了当地的公共群体性交通的状况,我才顿开茅塞.  相似文献   

18.
In the past decade public authorities have developed a wealth of creative funding mechanisms to support transit systems. This paper offers a taxonomy of various unconventional funding mechanisms (i.e. outside the domain of charges for transit passengers or general taxation schemes), based on a review of financial arrangements for public transport. The paper identifies which classes of funding are particularly successful for the financing of transit systems. This cross-sectional analysis uses a type of artificial intelligence method, viz. rough set analysis. It appears that the nature of the funding scheme and the degree of public acceptability are mainly responsible for the success of unconventional funding mechanisms.  相似文献   

19.
Trip chaining as a barrier to the propensity to use public transport   总被引:1,自引:0,他引:1  
Hensher  David A.  Reyes  April J. 《Transportation》2000,27(4):341-361
Trip chaining is a growing phenomenon in travel and activity behaviour. Individuals increasingly seek out opportunities to minimise the amount of travel required as part of activity fulfilment, given the competing demands on time budgets and their valuation of travel time savings. This search for ways of fulfilling (more) activities with less travel input has produced a number of responses, one of which is trip chaining. A particularly important policy implication of trip chaining is the potential barrier it creates in attracting car users to switch to public transport. This paper seeks to improve our understanding of trip chaining as a barrier to public transport use. A series of discrete choice models are estimated to identify the role that socio-economic and demographic characteristics of households have on the propensity to undertake trip chains of varying degrees of simplicity/complexity that involve use of the car or public transport with an embedded commuting or non-commuting primary purpose. Multinomial logit, nested logit and random parameter logit models are developed and contrasted to establish the gains in relaxing the strict conditions of the multinomial logit model.  相似文献   

20.
This study develops a model that explains public transit ridership in Orange Country, California over quarterly periods during the 1974–1988 period. The model uses a Cobb-Douglas functional form and a Cochrane-Orcutt iterative procedure to measure the association between public transit ridership and the potential number of users, relative level of public transit service, relative price of public transit, seasonality, and external shocks. Relative measures of the explanatory variables are used to reduce the potential for multicollinearity and give greater confidence in the reliability of the estimated elasticities. The model is then used to prepare conditional quarterly forecasts for ridership in 1988 and unconditional quarterly forecasts during the 1989–1993 period.  相似文献   

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