Showing papers in "Travel behaviour and society in 2015"

High-speed rail networks, economic integration and regional specialisation in China and Europe

Abstract: The role of transport in the process of economic development and integration remains an area of controversy. Policy makers, faced with the claim that the cost of high-speed rail (HSR) makes it an expensive way of achieving the supposed benefits, seek to identify wider economic impacts through productivity gains as a justification. This paper explores the development of HSR as an instrument for promoting economic integration both through enhancing competitiveness and achieving greater economic cohesion in China and the European Union. The paper examines changes in accessibility and provides evidence on changes in specialisation for both main cities and their hinterlands. The evidence confirms that impacts differ widely and that the process of convergence and divergence differs at different stages of economic development.

Telecommuting, income, and out-of-home activities

Abstract: Telecommuting is on a rising trend as one of the most important alternative work arrangements. This paper explores whether telecommuters conduct more out-of-home activities than their non-telecommuting counterparts. More importantly, this paper investigates activity differences between low- and high-income telecommuters. This study draws a sample of approximately 7,500 workers from the 2007 Chicago Regional Household Travel Inventory. We use a Poisson model to estimate the number of out-of-home activities, and use an instrumental-variables (IV) approach to address the potential self-selection issue of telecommuting. We also identify workers who worked at home (WAH) during the survey days. Results show that telecommuting status and whether the respondents WAH on survey days affect out-of-home activities. During the survey days, low-income workers were less likely to telecommute than high-income workers, but those who actually telecommuted were similarly likely to conduct a higher number of total trips, pick-up/drop-off trips, and maintenance/discretionary trips, but fewer commute trips than the high-income telecommuters. Even on the days when telecommuters went to workplaces, telecommuting status is still associated with more trips. The behavioral difference between telecommuters and non-telecommuters on commuting days suggests that such disparity stems from unobserved differences between the two groups of workers rather than from the saved commute time through telecommuting.

Benchmarking vehicle and passenger travel characteristics in Delhi for on-road emissions analysis

Abstract: In a mega-city like Delhi, vehicle exhaust emissions play a central role for urban air quality management, and measuring these on-road emissions in an environment with mixed fuels, mixed engine sizes, mixed technologies, and mixed usage patterns, is a challenging task, which means a better understanding of the vehicle and the passenger characteristics in the city is necessary. In this paper, we present a series of survey methods – vehicle owners’ interviews at fuel stations, on-road observational studies, and use of data resources like vehicle registrations and pollution under check program, which can be utilized to benchmark parameters linked to an emissions inventory methodology (Activity–Share–Intensity–Factor – ASIF). We present estimates for fuel efficiency, age profiles, annual mileage, and number of in-use vehicles for cars, motorized two-wheelers (2Ws), three-wheeled scooter rickshaws (3Ws), and buses and modeled survival functions for cars and 2Ws using log-logistic distribution function. In addition, using GPS data logging, we evaluated speed distribution of buses, cars, 2Ws and 3Ws, which resulted in evaluating the modal idling times, all of which were utilized to develop a robust vehicle exhaust emissions inventory for Delhi – segregated by vehicle type, fuel type, and age group. The survey methods and analytical techniques are simple and fast to implement, which when replicated, can provide a useful data source to estimate on-road transport emissions in urban areas.

Challenges and opportunities in developing urban modal shift

Abstract: Continued urbanisation, and the resultant increase in urban trips, presents one of the greatest challenges to the environmental, economic and social sustainability of society. Given that the modal split between transport modes has remained relatively unaltered in recent decades, this suggests that the levels of private car usage will lead to even greater levels of congestion and air pollution in urban areas. Therefore, a modal shift from private to public transport needs to be effected with urgency. However, whilst in theory this could be achieved with relative ease, numerous societal, political and economic barriers have thus far prevented such a shift from occurring. These have been analysed in detail, using a holistic approach which simultaneously considers all stakeholder needs. Recognising that traveller opinions and requirements are fundamental in effecting modal shift measures, the effects of public transport quality attributes on encouraging modal shift are discussed, accompanied by an updated version of the UK Department for Transport’s hierarchy of public transport needs. This investigation then proceeds to analyse the effectiveness of methods to control urban car usage, before discussing solutions to address the barriers to a notable, successful modal shift, including guidance on how to design modal shift programmes. This paper provides useful and insightful guidance for all those involved in attempting to evoke sustainable mobility through a modal shift to public transport systems.

Not all prospective bicyclists are created equal: the role of attitudes, socio-demographics, and the built environment in bicycle commuting

Abstract: Barriers to bicycling may vary widely depending on individual, attitudinal, and built environment characteristics; barriers may be modest for some (e.g. requiring secure bike parking) or significant for others (e.g. improving regional bicycle-accessibility). This research suggests that for a substantial population of travelers who are interested in bicycling but unwilling to cycle regularly, barriers to increasing commute cycling may be different than for individuals who already commute by bicycle at least occasionally. Treating these two populations as one homogenous group may be inappropriate and reduce the effectiveness of bicycle promotion strategies. This research disaggregates these two prospective commute-cyclist populations and tests how attitudes, socio-demographics, and the built environment impact their commute mode choice. Socio-demographic and attitudinal data are drawn from a survey of “Bike to Work Day” participants in Denver, Colorado while built environment measures – including street network connectivity, street network density, and trip distance – were calculated with GIS. Bicycle commuting decisions within the two groups of prospective cyclists are estimated using binary and ordered logistic regression. Distinct socio-demographic and built environment factors are significant for different groups of prospective cyclists. Significant attitudinal variables are similar across groups; for both populations, convenience and utility of the bicycle relative to other modes is significant, suggesting that these factors outweigh issues regarding safety for the sample population. Findings from this research demonstrate that there are important distinctions between the decision to start commuting by bicycle and the decision to increase the frequency of bicycling to work.

Do aging populations have differential accessibility to activities? Analyzing the spatial structure of social, professional, and business opportunities

Abstract: Accessibility is facilitated by well-organized transportation systems that move people efficiently, and it is improved as more activities are reachable to people given the means of available travel. As the current population ages, it will ultimately challenge those who manage transportation systems in their attempts to satisfy the older population’s basic needs. Scanning the literature, accessibility has not been fully explored in relation to aging and older populations. We construct a systematic quantitative analysis of the older population’s accessibility to potential activities. Given their residential patterns and the prevailing transportation system, we ask whether they have as much potential accessibility to activities as their younger counterparts. Our study area is a smaller metropolitan area in the state of Florida. Using highly disaggregate spatial data containing the locations of populations and possible activities, we implement accessibility models in a Geographic Information Systems (GIS) environment, accounting for mode of transportation. Scenarios and activities analyzed are informed by a review of the broader literature as well as our own analysis of the 2009 National Household Travel Survey. We find that the potential accessibility of the aging population varies by activity type and differs with other age group cohorts. When we look in detail at subgroups within the aging population, the oldest group (those 85+) tends to have higher levels of accessibility.

Accounting for the short term substitution effects of walking and cycling in sustainable transportation

Abstract: The environmental benefits of bicycling and walking depend on the degree to which their use substitutes for car driving. Assuming that every walking and bicycling trip replaces a driving trip is likely to produce overestimates of the potential for such modes to reduce vehicle travel and city-scale greenhouse gas emissions. Measuring this “substitution effect” is not straightforward. There are many dimensions of the substitution effect, including trip type, substituting mode, extent, time horizon, and activity patterns. Previously used approaches to measure substitution include indirect inference and direct questioning. This study piloted an intercept survey using the direct questioning approach at five locations in two metropolitan areas. The rate at which utilitarian walking or cycling trips substituted for auto trips ranged between 25% and 86%. Logistic regression models demonstrate that disparate factors explain walking substitution and bicycling substitution behavior; age is significantly correlated with substitutive walking behavior while number of car trips per week and helmet use are each significant predictors of bicycle substitution. This research represents a valuable first step toward developing a method to estimate the substitution effect that is useful for practitioners. Better estimates of the substitution effect will in turn lead to better estimates of the environmental impacts of bicycling and walking.

Exploring frequency of public transport use among older adults: A study in Adelaide, Australia

Abstract: Population ageing presents formidable challenges to transport systems in developed countries and many developing countries. While public transport is particularly important for older adults in terms of modal shift and social exclusion, there has been limited understanding of factors affecting the frequency of their public transport use. This paper presents results of an empirical study that explores factors influencing the frequency of public transport use among older adults in Adelaide, Australia. Multinomial logistic regression is used to model the frequency of public transport use while multiple correspondence analysis is used to capture non-linear relationships among the frequency of public transport use and influencing factors. Results show that more frequent use of public transport is closely associated with very high perceived importance of public transport to residential locations and easy access to public transport in neighbourhoods (perceived walking time to stops of five minutes or less and stop density of at least four stops within 400 metres of residential locations). Results also suggest public transport might be preferred to driving by older adults for travel during high-pressure driving periods such as peak hours. In addition, mobile phone possession is found to increase the likelihood to use public transport.

Economic and environmental impacts of energy subsidy reform and oil price shock on the Malaysian transport sector

Abstract: This study employs a multi-sector computable general equilibrium model to investigate the long-run impacts of three scenarios, namely high prices of petroleum products, energy subsidy reform and the combine of both, on the Malaysian transport sector. The long-run simulation results suggest that all shocks are beneficial for the entire economy because of the increase in real GDP and investment. The shocks encourage the reallocation of resources and therefore induce disparities in sectoral adjustments. All transport sectors, except water transport, gain from high petroleum prices due to the increase in their domestic output, domestic sales and exports, while they lose from the energy subsidy reform and the combined scenario. The shocks lead to significant changes in travel behaviour of all household types through a change in their use of transport sub-sectors. The combined scenario followed by the high petroleum price shock greatly reduces energy consumption and emissions of all air pollutants in the transport sectors. These findings enhance our understanding of the transport impact of oil price shocks and energy subsidy reform and should be of much interest to scholars, corporate executives, travel agencies, regulators, and policy makers.

Children's travel and incidental community connections

Abstract: This article looks at the effect that social interactions during travel have on children. The authors investigate how the build environment and mode of travel affect the chance of a child seeing ot ...

An empirical investigation of attitudes toward waiting on the part of Northern California commuters

Abstract: Using a sample of 2849 commuters in Northern California, this paper offers a first effort to identify latent constructs associated with a general orientation toward waiting. The bi-factor analysis of 11 items revealed a single dimension capturing a general like/dislike of waiting, together with two domain-specific factors representing attitudes of “waiting is OK if I expect it” and “I don’t need to be equipped when waiting”. We compared mean factor scores across socio-economic groups based successively on gender, income, presence of children, primary commute mode, and the number of productivity tools carried on the commute. Although sample size contributed to statistical significance, effect sizes in most cases were modest. Nevertheless, women tended to have more favorable attitudes toward waiting than men (including a greater tolerance of expected waiting and a greater inclination to be equipped). Higher-income respondents tended to view waiting less favorably, and were more inclined to be equipped to wait. Those with children at home were less tolerant of expected waiting than others. Users of public transit or active commute modes (walking/biking) tended to view waiting more positively. Respondents who are more tolerant of waiting and have a proclivity to be equipped for a wait event tend to carry more productivity tools during their regular commute, such as books and magazines, tablets, smartphones, and music players.

A new psychological methodology for modeling real-time car following maneuvers

Abstract: In this paper a new structure of car following is proposed, and the psychological point of view is investigated in it. In general, most car following models have been investigated from the physical point of view, but in this paper, it is shown that in order to find a more realistic model for car following, not only does the physical point of view have to be considered, but also this model has to be investigated from psychological and control-engineering points of views too. In the rest of the paper, the psychological point of view in the proposed structure for the car following model is investigated in detail. In order to do this, some scenarios are designed with the aim of investigating drivers’ behavior; then, these scenarios are applied to 65 different drivers using different simulators. By analyzing the data gathered from the scenarios, the related parameters of the proposed model are estimated, and the distributions of the values of the parameters are shown. In the end, some suggestions for investigating the control-engineering point of view in the proposed car following structure in this study are presented. The results of this research are of great importance in applying car following models in different driving simulators and also in every research where there is a need for a more realistic car following model.

Let it rain: Weather effects on activity stress and scheduling behavior

Abstract: Travel and activity scheduling decisions largely depend on travelers’ responses to prevailing trip conditions. These could be impacted by environmental situations, such as adverse weather, which can increase the variability in travel times, practical capacity and other system properties. Understanding and modeling the relationship between travel and activity decisions and adverse weather is important for devising and evaluating transportation management strategies that rely on adjustments and shifts in behavior. This study focuses on the impact of rainfall precipitation on activity decisions, more specifically the perceived stress underlying these decisions. In the current study, activity scheduling decisions for discretionary activities are examined under different rainfall levels, but given consistent data on other forms of precipitations, such as snow sleet or hail, this study could be extended to these cases. Activity stress is modeled under a discrete choice framework. The results show that the perceived activity stress differs under rainfall to some extent, depending on the number of activities in a traveler’s activity queue, and the number of activities completed. The study also reveals that travel behavior may differ under rainfall, suggesting that travelers’ may perceive information and uncertainty differently, relative to conditions with less variability in weather. Furthermore, issues concerning climatology data requirements for transportation models are discussed.

The role of source preference and subjective probability in valuing expected travel time savings

Abstract: This paper proposes a fully subjective approach to capture the impact of travel time variability on travel decision making that accommodates subjective probabilities and source preference, the latter construct referring to respondent preferences to make judgments on matters that they have reasonable if only vague beliefs about than on matched chance events. The methods of eliciting subjective probabilities and source preference are discussed together with a suggested way forward to introduce, and hence capture parametrically, attitudes towards uncertainty. Using a 2014 survey of commuters in Sydney, we provide examples of modelling source preference and the implications for valuing expected travel time savings. The paper highlights the limitations of stated choice experiments when subjective attribute levels and their occurrence are relevant, suggesting a return to a revised focus on revealed preference data.

Transit commuting market investigation using the latent segmentation approach

Abstract: This study employs a latent segmentation approach to investigate the commuting market, with focus on the usage of public transit. The factor–cluster analysis technique is used to systematically deal with multi-dimensional psychological statements, and then segment the whole sample into homogenous groups. A six-cluster solution is arrived, each with distinct combinations of latent factors, including attitude, perception, habit, and intention to use public transit. On account of the unique psychological profile of each segment, related measures and strategies are proposed to promote the choice of public transit for each sub-segment. The results demonstrate that individuals within different segments must be treated in different ways since their behavior are motivated by different factors.

Investigating the influence of Vehicular Ad-hoc Networks on driver behaviours and traffic accidents

Abstract: One of the objectives of transportation engineers is to maximize safety in road networks while preserving their appropriate efficiency. This could be done by improving the existing projects or enhancing design standards for new transportation components. Another important use of traffic safety studies relates to the investigation of changes taking place in the existing safety level as the characteristics of road system changes, and studies before and after the changes. In this paper, we attempt to assess the effects and role of Vehicular Ad-hoc Networks (VANETs) in enhancing road safety and reducing the number of rear-end collisions in freeways by reducing drivers’ reaction time in facing critical situations. In so doing, the study deploys the new Urgent Deceleration Index (UDI). This paper comprises five sections. In the second section, we review the literature including introducing Vehicular Ad-hoc Networks (VANETs) and car-following models; introducing and comparing time headway (THDW), Time to Collision (TTC), the time exposed to TTC (TET) index, and the new Urgent Deceleration Index (UDI). In the third section, the research methodology of the assessment of safety before and after the use of VANETs by using the UDI index will be described. In the fourth section, we present the results of analysis including the calculation of the percentage of time that the vehicles are exposed to danger in the process of car-following, before and after the establishment of intelligent connection between vehicles. And finally, the fifth section offers conclusions and suggestions for further research. Language: en

Are citizens not accurately informed about long-term societal costs of unsustainable travel or do they not care?

Abstract: We argue that people think more about the short-term individual benefits of personal motorized travel than the long-term societal costs. One explanation is that people are more concerned about their own wellbeing and the wellbeing of their close relatives than the well-being of unknown others. Another explanation is that people have less knowledge of the long-term societal costs than of the short-term individual benefits. Research findings documenting long-term societal costs may increase this knowledge if accurately conveyed by governments, mass media, producers and providers of travel services, and opinion leaders. We identify several obstacles to such an accurate dissemination of research findings that need to be removed.

Phone call elasticity of city travel in Ahmedabad

Abstract: The new era of Information and Communication Technologies ICT enables people to communicate and interact with each other in different manner, changing the way they conduct their lives. This change has significant implications on their physical travels. The relationship between ICTs and travel is complex and sometimes indirect. This paper aims to better understand this complex relationship by empirically analyzing the substitution versus additive effects of phone calls on physical distance traveled by individuals. This is done by analyzing the phone call elasticity of physical travel. The analysis also studies the relevance of social ties in Ahmedabad, India, as a source of explanation of social activity, thus travel, undertaken by individuals. Social Network Analysis (SNA) allows capturing social determinants that affect travel in a way socio-demographics do not capture. The phone call elasticities show a variation among different people which can be connected to the type of trips that are substituted. The substituted trips are related to the social networks of individuals. Decision makers can use this tool to designing their travel and ICT policies in a novel way.