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1.
Marsden  Greg  McDonald  Noreen C. 《Transportation》2019,46(4):1075-1092

Future travel demand has always been difficult to estimate. Recent trends of a slow down or stagnation in traffic growth combined with substantial demographic, economic, and technological shifts further complicate that task. This poses a significant planning challenge given that decision-making is often based on the benefits of infrastructure investments which accrue over periods as long as 60 years. In contrast to the changing ideas around what mobility in the future will look like and the types of demand it may need to service, the practice of forecasting future travel demand remains largely unchanged as do the decision-making processes which flow from this. Alternative approaches to thinking about futures such as scenario planning exist but have had more limited deployment in the transport sector. This paper explores the institutional issues surrounding the purpose, practice and barriers to changing the approaches of forecasting and decision-making through an exploration of the state of practice in the UK drawing on interviews with 23 practitioners. Drawing on Hall’s work on policy change, the research finds that there is a strong policy paradigm built around the relationships between transport investment and traffic growth. This has strengthened since the recession with an increased focus on the relationship between transport and job creation. The forecasting approaches in use today are an important part of a complex decision-making apparatus reflective of specialized policy arenas like transport. Challenges in acknowledging, representing and communicating uncertainty are identified leaving a growing tension between planning visions and planning practice. We conclude by reflecting on events which may stimulate a broader reframing of how we plan for transport futures whilst embracing key uncertainties.

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2.
The paper develops a model to represent the cost structure of European railways based on a general index of technical change, which allows completely general estimation of productivity growth. The estimated model is based on a variable cost function for panel data, which allows for heterogeneity in spite of previous approaches in the railway economics and general index model literature which adopt the assumption of common technical parameters across countries.  相似文献   

3.
Abstract

Road congestion remains a serious problem, despite all the efforts to limit road use and to manage growing road traffic volumes. Economic approaches (such as pricing) are introduced based on traditional welfare economic theory. Although they are sometimes very successful, the magnitude of traffic issues also requires alternative and unconventional approaches. Perhaps a more innovative perspective is needed. The paper discusses an alternative economic approach starting from property rights theory. It is translated in transport systems in concepts of infrastructure capacity slot management, where slots are dynamically priced and exclusively allocated to individual users. Debates and practices regarding this approach in air traffic and rail traffic are further developed than in the field of road traffic. The paper aims to explore the potential benefits and disadvantages of the property rights approach for road traffic. Attention is paid to major institutional and technical conditions. The conclusion is that the approach theoretically has clear advantages and seems technologically feasible. Nevertheless, serious political and institutional issues have to be solved first.  相似文献   

4.
The field of transportation attracts individuals from diverse backgrounds, seeking to make contributions to policy, planning, operations and strategy. Economists are one of the more visible subsets of players, who bring a specific focus to the transport problem. The key theme of this paper is economic efficiency and ways that transport economics seeks to achieve efficient outcomes in the presence of markets and institutions that to varying degrees distort the potential to fulfil this primary goal. We review some of the recent contributions to the literatures on institutional and market reform, travel choice and demand. As we enter the next century, there is a sense of promoting ‘back to basics’ (and redefinition of what skills transport specialists will require) in seeking a better understanding of the role of markets and institutions in guiding the destiny of the transport sector.  相似文献   

5.

The paper considers in detail strategic changes occurring in the organizational context of intermodal transportation and discusses the application of economic approaches (primarily transaction-cost economics) for assessing the effectiveness of the appropriate governance structure in organizing the intermodal transport economic system. The paper reviews the developments in intermodal transportation, particularly in the context of logistics and supply chain management, and recognizes the trend for the formation of one-stop shopping megacarriers spurred by deregulation and market requirements. This culminates in the need to consider how companies should organize the economic governance of the intermodal transport system. The main governance structures include market (subcontracting) or hierarchy (internal organization). The transaction-cost economics approach is reviewed and applied at a conceptual level to provide the core basis upon which the assessment of the optimal governance structure in intermodal transport can be based. The review of the core economic principles indicates that the governance structure in intermodal transport is dependent on transaction costs, production costs and strategic considerations that a particular structure might entail and the policy implications thereof. The potential for empirical research in the application of the transaction-cost economics approach to intermodal transport is discussed and detailed direction for further empirical research is provided as well as discussion of policy implications particularly with respect to competition and antitrust.  相似文献   

6.
In recent years smartcards have been implemented in many transit systems around the world as a means by which passengers pay for travel. In addition to allowing speedier boardings there are many secondary benefits of smartcard systems including better understanding of travel patterns and behaviour of travellers. Such research is dependent on the smartcard correctly recording the boarding stop, and where available the alighting stop. It is also dependent on the smartcard system correctly aggregating individual rides into trips.This paper identifies causes for why smartcard systems may not correctly record such information. The first contribution of the paper is to propose a set of rules to aggregate individual rides into a single trip. This is critical in the research of activity based modelling as well as for correctly charging the passenger. The second contribution of the paper is to provide an approach to identify erroneous tap-out data, either caused by system problems or by the user. An approach to detecting this phenomenon is provided. The output from this analysis is then used to identify faulty vehicles or data supply using the “comparison against peers approach”. This third contribution of the paper identifies where transit agencies and operators should target resources to improve performance of their Automatic Vehicle Location systems. This method could also be used to identify users who appear to be tapping out too early.The approaches are tested using smartcard data from the Singapore public transport network from one week in April 2011. The results suggest that approximately 7.7% of all smartcard rides recorded the passenger as alighting one stop before the bus stop that they most probably alighted at. A further 0.7% of smartcard rides recorded the passenger as alighting more than one stop before the bus stop that they most probably alighted at. There was no evidence that smartcards overestimated the distance travelled by the passenger.  相似文献   

7.
Car following models have been studied with many diverse approaches for decades. Nowadays, technological advances have significantly improved our traffic data collection capabilities. Conventional car following models rely on mathematical formulas and are derived from traffic flow theory; a property that often makes them more restrictive. On the other hand, data-driven approaches are more flexible and allow the incorporation of additional information to the model; however, they may not provide as much insight into traffic flow theory as the traditional models. In this research, an innovative methodological framework based on a data-driven approach is proposed for the estimation of car-following models, suitable for incorporation into microscopic traffic simulation models. An existing technique, i.e. locally weighted regression (loess), is defined through an optimization problem and is employed in a novel way. The proposed methodology is demonstrated using data collected from a sequence of instrumented vehicles in Naples, Italy. Gipps’ model, one of the most extensively used car-following models, is calibrated against the same data and used as a reference benchmark. Optimization issues are raised in both cases. The obtained results suggest that data-driven car-following models could be a promising research direction.  相似文献   

8.
Abstract

Following the historical evolution of urban transport in South America, the authors show the economic, technological and cultural facts that have governed its development until today.

The paper, mainly based on experience in large Brazilian cities, gives facts and figures about some of the most important towns where different approaches to urban transport were tried. Information about other South American countries is also given and discussed.

The article details the evolution, current situation and new plans in Sao Paulo city, describing concession criteria, modal split and the economics of the different modes in operation today and planned for future use, ending with the general influence of Sao Paulo experience of urban transport systems in many other Brazilian cities.  相似文献   

9.
Short-term prediction of travel time is one of the central topics in current transportation research and practice. Among the more successful travel time prediction approaches are neural networks and combined prediction models (a ‘committee’). However, both approaches have disadvantages. Usually many candidate neural networks are trained and the best performing one is selected. However, it is difficult and arbitrary to select the optimal network. In committee approaches a principled and mathematically sound framework to combine travel time predictions is lacking. This paper overcomes the drawbacks of both approaches by combining neural networks in a committee using Bayesian inference theory. An ‘evidence’ factor can be calculated for each model, which can be used as a stopping criterion during training, and as a tool to select and combine different neural networks. Along with higher prediction accuracy, this approach allows for accurate estimation of confidence intervals for the predictions. When comparing the committee predictions to single neural network predictions on the A12 motorway in the Netherlands it is concluded that the approach indeed leads to improved travel time prediction accuracy.  相似文献   

10.
The role of anticipated time pressure in activity scheduling   总被引:1,自引:0,他引:1  
In the present article we focus on the cost or disutility of engaging in activities arising from the time pressure people frequently experience when they have committed themselves to perform too many activities in a limited amount of time. Specifically, we propose that anticipated time pressure increases the likelihood of two types of planning, one short-term and the other long-term encompassing different strategies for eliminating or deferring activities. In addition, we discuss several behaviorally realistic such strategies. It is assumed that strategies differ depending on whether an activity satisfies physiological needs, is performed because of institutional requirements or social obligations, or is performed because of psychological or social motives. Strategies are also assumed to differ depending on the degree to which planning is feasible. Computer simulations of available activity data are presented to illustrate consequences of the different strategies on time pressure and activity agendas.  相似文献   

11.
《运输评论》2012,32(1):76-94
ABSTRACT

This paper looks at the economics of ridesourcing (or app-based ride-hailing) with a particular focus on the US. It brings together the rather dispersed literature on the subject focusing on the economic characteristics of the underlying industry and sets this within the broader context of transportation economics. In particular, it sorts out the realities of ridesourcing from some of myths that were perpetrated in its early days and, in many cases, still persist. It considers some of the empirical evidence that has emerged regarding the key parameters that determine the way Uber and the like operate, and the welfare implications of this, together with comments on some of the regulatory reactions to the new transportation platform. It concludes by suggesting some ways in which recent developments in economic could move forward our understanding of the industry as technologies and markets change.  相似文献   

12.
This paper reviews and critically assesses procedures which have been adopted to evaluate Advanced Transport Telematics (ATT) projects. The importance of such a review at this juncture stems from the changing position of ATT in transport planning. ATT is no longer simply a field for experimentation, where technical feasibility and user acceptance are dominant concerns. Rather it is a potential mainstream contributor to the functioning of road transport systems. For this reason, ATT project appraisal needs to be developed to the same form, level of sophistication and consistency as the appraisal of conventional transport infrastructure investment. Based on the review set out here, we argue that appropriate methods have not yet been established which, in turn, poses a number of challenging questions, since current socio‐economic evaluation procedures are not directly suited to either measuring or evaluating many of the impacts which ATT schemes are implemented to achieve.  相似文献   

13.
Efforts to reduce energy use in freight transportation usually center around “mode-based” approaches, namely improving the energy efficiency of energy intensive modes, such as truck, and shifting more freight to energy efficient modes, such as rail. In the first part of this paper we review the recent trends and future prospects for these mode-based approaches, finding that despite substantial improvement in the technological efficiency of freight modes and robust growth in the use of intermodal rail since 1980, total freight energy use across all modes in the US has grown by approximately 33%, with proportional growth in carbon emissions. In the second part of the paper we propose use of a “commodity-based” approach, in which freight energy use is disaggregated by contribution of major commodity groups, in order to support efficiency improvement at the commodity level. Two potential applications of the commodity based approach, namely (1) life cycle analysis of energy use for major commodity groups and (2) spatial analysis of freight patterns, are demonstrated using the 1993 US Commodity Flow Survey data. Results of these preliminary findings suggest that commodity groups vary widely in the ratio of energy use in production to energy use in transport, and that for many commodity groups, there may be substantial opportunities for saving energy by redistributing flow patterns. Through development of the commodity-based approach, we also identify the collaborative involvement of shippers and carriers as a key point in improving energy efficiency, since it can be used to both make the mode-based approach more effective and address new issues such as the underlying growth in tonne-km. Benefits for air quality and other transportation issues are also discussed.  相似文献   

14.
This paper describes and seeks to understand the scale of the electric bicycle (electric two-wheeler) market in China, and to begin to explain its emergence with a view to outlining the prospects for learning from this case for applications in other countries around the world. Drawing on secondary data from Chinese government sources, electric bicycle industry websites, Chinese media sites and other sources, this exploratory paper positions the development of the electric bicycle market as occurring largely in the absence of positive policy intervention – in stark contrast to the nurturing afforded the electric car sector world-wide. The paper develops a multi-scalar perspective of transitions theory in an institutional setting, with examples drawn from Beijing and Fuzhou, to explain the processes of change outside of the traditional reference context of technology policy and management. It is concluded that transitions theory has a greater flexibility and adaptability as an explanatory framework than previously shown, but empirically the electric two-wheeler is a weakly-embedded alternative to mainstream automobility.  相似文献   

15.
In China, many rural migrant workers experience residential segregation and live in urbanizing villages, due to China’s unique institutional context (e.g. land tenure system, hukou system) as well as exclusionary housing regulations. The purpose of this paper is to investigate whether these urbanizing villages provide good job accessibility for rural migrant workers. We explore this problem by investigating the commuting patterns of migrant workers. Through a survey conducted in 2009 across four mega-regions in China that are currently experiencing rapid urbanization, we collected individual level information on rural migrant workers’ commute distances and durations, demographics, household socioeconomic status, and whether the migrant worker is living in an urbanizing village or not. From residential address information collected in the survey, we constructed a group of built environment variables. Using IV Tobit models to address the endogeneity issues associated with residential location choice, our analyses show that these urbanizing villages actually provide relatively good accessibility to job opportunities. This result is different from what is suggested by the spatial mismatch literature based on U.S. data. This research helps to fill the gap in the literature on the relationship between residential segregation, built environment and travel behavior in the Chinese context. The findings have implications for policymaking, especially when many government officials are proposing to demolish urbanizing villages without fully realizing the benefits of these villages. This research could also provide useful information for other developing countries facing residential segregation of migrants or immigrants.  相似文献   

16.
Retail traffic is one of the main drivers for the growth of intermodal transport services in the UK. This paper examines the key factors underpinning this modal shift in order to learn lessons for other market and geographical contexts. Since successful retail intermodal logistics involves many actors, this paper is based on semi-structured interviews with major UK retailers, third-party logistics providers (3PLs) and rail operators, supplemented by document analysis. The qualitative data are analysed via a conceptual framework derived from the literature. Despite past successes and the presence of drivers for future growth, the paper identifies many operational issues without current solutions and the presence of ongoing public subsidy. The major conclusion is that the importance of 3PLs, aggregation and multi-user platforms must be recognised by transport planners in supporting the use of intermodal transport by retailers and other large shippers.  相似文献   

17.
This paper reports on the use of different approaches for measuring the efficiency of major Brazilian port terminals. Two of the most important approaches, DEA (Data Envelopment Analysis) and SFA (Stochastic Frontier Analysis), were performed on data collected from 25 terminals. The findings indicate that the majority of Brazilian terminals are running short on capacity due to the export boom that has occurred over the past few years and due to the lack of investment in capacity expansion. Furthermore, efficiency measurements derived from a reduced model with only one input and one output were explained based on variables such as type of cargo handled (container or bulk), connectivity of the terminal to railroads, and control (state or private) of the terminal. Implications and directions for future research are explored.  相似文献   

18.
This paper presents a taxonomy and analysis of the content of published research in port economics, policy and management (port studies). The recent increase of these publications suggests a growing interest in the study of ports. However, the research characteristics and directions of this research field are unidentified. This paper provides a systematic analysis of port studies published during the period 1997–2008. A comprehensive cross-citation and analysis of the themes, approaches and findings of all 395 relevant journal papers identifies the extent to which the research field is maturing, and the leading papers. This paper also presents an extensive analysis of the content, based on the classification of all port studies into seven research themes. For each theme, research topics, widely used research questions, concepts and research methods and the most important research findings are discussed. Finally, we identify emerging research challenges and research questions that still need to be answered.  相似文献   

19.
We compare the passenger transportation systems of Buenos Aires, Chicago and São Paulo. The selected cities represent distinctive combinations of land-use, infrastructure, and evolution of transport policy. Analysis is centered on accessibility to downtown areas, where transportation processes converge in an environment where space is scarce. In two of the three cities institutional arrays that legally establish unified decision making have shown little capacity to launch fare or physical coordination between modes. In two of the three cities the concentration of public transportation supply to historical downtowns has not been an attraction factor, and downtown uses have expanded to less accessible areas. Gentrification in Chicago is also another process showing that land use changes are related to many factors, transportation being only one of them, and not always a necessary one. In all three cases the use of railways, as a set of inherited infrastructures, has seen an increase whose magnitude suggests a link to modal reassignment due to increasing congestion. Scarcity of space in old downtown areas is being counteracted through more intense use, or through the expansion of vertical space for transportation operations.  相似文献   

20.
Toll road competition is one of the important issues under a build-operate-transfer (BOT) scheme, which is being encountered nowadays in many cities. When there are two or more competing firms and each firm operates a competitive toll road, their profits are interrelated due to the competitors' choices and demand inter-dependence in the network. In this paper we develop game-theoretic approaches to the study of the road network, on which multiple toll roads are operated by competitive private firms. The strategic interactions and market equilibria among the private firms are analyzed both in determining their supply (road capacity) and price (toll level) over the network. The toll road competition problems in general traffic equilibrium networks are formulated as an equilibrium program with equilibrium constraints or bi-level variational inequalities. Heuristic solution methods are proposed and their convergences are demonstrated with simple network examples. It is shown that private pricing and competition can be both profitable and welfare-improving.  相似文献   

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