On the income elasticity of the value of travel time

Transport infrastructure is long-term and in appraisal it is necessary to value travel time savings for future years. This requires knowing how the value of time (VTT) will develop over time as incomes grow. This paper investigates if the cross-sectional income elasticity of the VTT is equal to inter-temporal income elasticity. The study is based on two identical stated choice experiments conducted with a 13 year interval. Results indicate that the relationship between income and the VTT in the cross-section has remained unchanged over time. As a consequence, the inter-temporal income elasticity of the VTT can be predicted based on cross-sectional income elasticity. However, the income elasticity of the VTT is not a constant but increases with income. For this reason, the average income elasticity of the VTT in the cross-sections has increased between the two survey years and can be expected to increase further over time.     

Incomplete cost – incomplete benefit analysis in transport appraisal

This paper examines the current application of transport appraisal in the UK, in particular exploring the partiality of cost–benefit analysis (CBA) within the wider multi-criteria analysis (MCA) process. It argues that applying a quantitative assessment of the varied impacts of complex transport projects can only be partial within the CBA. Analysis can overlook social, human life, environmental and built environment impacts, and projects can be inconsistent with the planning strategy for an area. The application of CBA is critically reviewed using two case studies: the proposed upgrade of the South Fylde railway line and the Heysham-M6 Link Road, both from North West England. A participatory MCA process is suggested to help improve the process of transport appraisal, as part of an improved public debate on transport investment priorities.     

动态交通政策的长期优化设计--通过定价机制寻求社会福利最大化

针对交通政策设计中决策过程的可选方法展开探讨。探索对出行政策进行综合预测、评价、优化以实现决策方案最优的可能性。从长远来看,为了适应像城市这样一个动态系统,采用了用地与交通相互影响模型（LUTI）的长期评估方法。在评估的全过程中,通过成本效益分析来衡量实施LUTI动态决策所产生的社会福利,然后通过优化程序使其达到最大化。这一模型在马德里市收费站最优定价策略项目中得到验证,该项目要求保证系统效率、社会公平以及环境质量。与其他定价方案相比,最优方案能以相对较低的收费产生更多的社会盈余。该实践结果突出强调了不同因素对研究区域以及对社会福利盈余的主要贡献者的影响,从而反思采用的成本分析方法是否可以作为设计可持续政策的最佳方法。     

Cost effective future derailment mitigation techniques for rail freight traffic management in Europe

Safe and reliable traffic management is vital for uninterrupted and successful operation of the European rail network, where mixed traffic (i.e. freight and passenger) services are run. Although rail freight derailment is infrequent, its consequences can be severe and may result in different forms of costs, including infrastructure; rolling stock; traffic disruptions; injuries and fatalities. The objective of this research paper is to conduct a cost benefit analysis (CBA) to identify cost effective mitigation techniques for efficient rail freight traffic management in Europe, by 2050. Reviewing previous derailments and studies, eight sets of derailment causes are analysed and, for each of them, sets of mitigation techniques are aimed at for their alleviation. The study finds that the highest cumulative costs of derailment are associated with ‘wheel failure’, while the lowest cumulative cost is identified for ‘excessive track width’. Regarding mitigation techniques, the lowest cumulative benefits are demonstrated for ‘track height’ interventions, whereas ‘wheel failure’ alleviation demonstrates the highest benefits, in value terms (all by 2050). In most cases, the benefit to cost ratio did not exceed 2.6; in two cases (‘track height’ and ‘rail failures’) the ratio remained below 1 – a negative outcome where cost is higher than benefit. The study suggests that the most cost-efficient interventions are those applied to ‘hot axle box and axle rupture’ and ‘spring and suspension failure’.     

Transport Network Design Problem under Uncertainty: A Review and New Developments

This paper aims to provide a state-of-the-art review of the transport network design problem (NDP) under uncertainty and to present some new developments on a bi-objective-reliable NDP (BORNDP) model that explicitly optimizes the capacity reliability and travel time reliability under demand uncertainty. Both are useful performance measures that can describe the supply-side reliability and demand-side reliability of a road network. A simulation-based multi-objective genetic algorithm solution procedure, which consists of a traffic assignment algorithm, a genetic algorithm, a Pareto filter, and a Monte-Carlo simulation, is developed to solve the proposed BORNDP model. A numerical example based on the capacity enhancement problem is presented to demonstrate the tradeoff between capacity reliability and travel time reliability in the NDP.     

高校输送CBA所需人才制约因素的探索与思考

CUBA应该向CBA输送其所需要的后备人才.然而;十年的教育、训练实践表明:各普通高校的大学生运动员在毕业后能成为CBA一员的寥寥无几;从事体育专项运动的人才更是少之有限,文章仅就高校自身及目前国内培养体育人才的体制等方面入手,就高校输送CBA所需人才的制约因素进行探索与思考.     

Cost benefit analysis of three different urban bus drive systems using real driving data

One of the CIVITAS-ELAN project measures in Ljubljana, Slovenia, was the introduction of alternative city bus propulsion systems (CNG, hydraulic hybrid buses) into the public transport and comparison of their performance in terms of costs and benefits with conventional (diesel) buses. A cost-benefit analysis was conducted to provide a model for identifying the most attractive alternative, with aim of aiding the decision making process for future rational up-scaling of the alternative propulsion technologies in PT fleet in Ljubljana. This paper focuses on presenting the key findings of this CBA, using real driving data, while demonstrating the sensitivity/variance of different parameters of a CBA, as well as the differentiation between uncertainties of parameters in an ex-ante analysis versus an ex-post analysis.     

Attitudes towards the role of Cost–Benefit Analysis in the decision-making process for spatial-infrastructure projects: A Dutch case study

This paper provides a systematic overview of the attitudes of key actors in the Dutch Cost–Benefit Analysis (CBA) practice towards the role of CBA in the decision-making process for spatial-infrastructure projects. The main aim of this paper is to scrutinize the extent to which there is agreement among these Dutch actors in regard to the role of the CBA in the decision-making process. A secondary goal is to provide possible explanations for agreements and controversies among key actors in the Dutch CBA practice. In this study two research methods are combined to study the key actors’ attitudes. Firstly, 86 key actors (e.g. consultants, scientists, policy makers) were interviewed in-depth. Secondly, 74 of them completed a written questionnaire. The most important conclusion of this paper is that in the Dutch CBA practice there is agreement that CBA must have a role in the appraisal process of spatial-infrastructure projects. However, there is a lot of controversy among economists and spatial planners in the Dutch CBA practice concerning the value that is and should be assigned to CBA in the decision-making process. Economists predominantly believe that not enough value is assigned to the CBA in the decision-making process, whereas spatial planners predominantly think that too much value is assigned to the CBA. Both economists and spatial planners believe that this controversy is problematic as it results in debates about the pros and cons of CBA instead of the pros and cons of the spatial-infrastructure projects. This paper analyzes some solutions for this controversy.     

高速公路可变限速系统的社会经济影响评价

运用计算机对高速公路典型路段可变限速系统进行模拟,模拟结果表明在交通量等于或大于2800veh h出现明显的效益。根据行程时间和实际服务流量确定不同交通量情况下可变限速的最佳值,并基于行程时间的节省测度出各交通量条件下实施可变限速货币化的增量效益,进行了成本效益分析。采用DEA方法进行多目标综合评价,评价结果显示,在DEA的各方案中3200、3400、3600、3800veh h所对应的DMU是DEA有效的。本文还证明了DEA对ITS项目评价是很有适用价值的,它能够描述用货币单位难以测度,但可用某种定量指标表述的重要影响。     

Local public transport on the basis of social economic criteria

Applying the welfare economic approach it is demonstrated what the effects of certain supply changes in the local public transport will be and the potential of innovative demand management measures are examined. Straighter bus routes would reduce the average travel time from door to door. The travel time on the buses decreases and the frequency increases, which reduces waiting times at bus stops. Using smaller buses and more of them would also increase the net benefit, but increase the need for subsidisation. The peak within the peak in the morning is hard to handle by price policy alone. Introducing a small variation of the start of the school-day for high-school pupils would make investment- and operation cost savings possible, and the inconvenience costs for the pupils could be limited. It is only during peak hours in the main direction of peak travel and in the critical section of the line that optimal price becomes high relative to the present level. Zero fares in off-peak will be social profitable, but an increase in subsidy is needed. An introduction of these policy changes would give rise to a net social benefit of 30 million SEK per year in Linköping.