Estimating local car ownership models

Many studies in the transport demand literature have shown that income is an important factor in determining how many cars a household owns. When the models used to measure the strength of this relationship are estimated on cross-sectional data, they typically yield one overall value as the estimate. Local circumstances will, however, vary. This paper illustrates the use of the Geographically Weighted Regression technique to estimate the individual strength of this relationship for each of the United Kingdom electoral wards. Use of this type of model enables a wards’ income elasticity to be based on both the local estimate of the strength of this relationship and the current local level of car ownership. How the use of this local elasticity changes future forecasts of the size of the vehicle fleet is illustrated.     

Study of vehicle ownership for urban and rural households in India

Private vehicle ownership has been growing in double digits over the last decade. This paper examines the factors determining vehicle ownership for urban and rural households in India. Separate nation-wide disaggregate vehicle ownership models for urban and rural areas in India are developed using readily available consumer expenditure survey dataset. A consumption based proxy variable is assumed to represent economic standard of households. Comparison between vehicle ownership behavior of urban and rural households show that rural households are more inclined to own private vehicle than urban households with same economic standards. Amongst households with regular salaried members, rural households' preference to own two wheelers is greater than that of urban households. While the presence of elderly member or children is considered, urban households showed more preference to own four-wheeler than rural households. As a first nation-wise study to understand the differences in vehicle ownership behavior in urban and rural areas of India, this study provides a lot of useful insights which could be valuable to various stakeholders.     

The non-bulk market for rail freight in Great Britain

An increased role for rail freight is an objective of the British government. Limited growth potential exists in rail’s traditional bulk markets, so more non-bulk volume is needed. This paper focuses on non-bulk rail freight activity in Britain, through desk-based research and company interviews. It considers changes in both the intermodal and traditional less-than-trainload (LTL) markets over the last decade. Issues relating to the use of these two types of services are presented, covering the principal opportunities and major constraints. Growth potential for both intermodal and traditional LTL flows is identified, but success is dependent upon important pre-requisites being satisfied.     

Planning for an unpredictable future: Transport in Great Britain in 2030

This paper describes a research study, which explores alternative future scenarios for Great Britain in the year 2030 and the implications these have for travel demand and transport provision. Five alternative future scenarios are represented in the GB national transport model and forecasts are obtained for trip making, traffic levels, congestion and emissions in 2030. For all scenarios it is expected that there will be significant traffic growth. Traffic growth is restricted most in scenarios including distance-based road charging on motorways and trunk roads. However, congestion and carbon dioxide emissions are most effectively limited in scenarios with congestion-based road charging, major improvements to urban public transport and investment in new fuel technologies and in improving engine efficiency.     

Modelling the Visitor Experience in the Gardens of Great Britain

Traditional host-student internships always aim to provide positive real-world learning outcomes for students. The industry partners are often considered to benefit from the arrangement, primarily through recruitment opportunities and achieving corporate and social responsibility objectives. Supplementary host benefits can include knowledge exchange, such as receiving innovative ideas and the latest theories from the students, as well as developing a collaborative relationship with the university. It is these, usually peripheral, benefits that emerged as the key positive outcomes for the tourism industry stakeholders of an innovative destination immersion internship, conducted by the School of Tourism, The University of Queensland. A third key outcome, identified through the in-depth interviews, and not usually associated with internships, was engagement with the destination network. This paper reports on the industry participant's expectations, experiences and satisfaction with the destination-based internship program. In particular, the research considers the benefits and challenges beyond the established internship literature. The findings of this study show that there is broader scope and reciprocity from internship programmes than has previously been identified in the literature.     

A logistical perspective on the potential for modal shift of freight from road to rail in Great Britain

Freight modal shift from road to rail is a potential means by which the negative environmental and social impacts of transport can be reduced. This paper explores recent supply chain changes and assesses their impacts on the mode choice decision-making process, specifically addressing the implications for the use of rail. Despite many of the identified changes effectively making the use of rail more difficult, considerable evidence has been found of the potential for rail to attract new traffic. Much of the identified potential is unlikely to materialise, however, without improvements in rail network capability and capacity and a greater customer focus from rail freight operators.     

Shared autonomous vehicles and their potential impacts on household vehicle ownership: An exploratory empirical assessment

Emerging transportation technologies have the potential to significantly reshape the transportation systems and household vehicle ownership. Key among these transportation technologies are the autonomous vehicles, particularly when introduced in shared vehicle fleets. In this paper, we focus on the potential impact that fleets of shared autonomous vehicles might have on household vehicle ownership. To obtain initial insights into this issue, we asked a sample of university personnel and members of the American Automobile Association as to how likely they would consider relinquishing one of their household's personal vehicles if shared autonomous vehicles were available (thus reducing their household vehicle ownership level by one). For single-vehicle households, this would be relinquishing their only vehicle, and for multivehicle households (households owning two or more vehicles) this would be relinquishing just one of their vehicles. Possible responses to the question about relinquishing a household vehicle if shared autonomous vehicles are present are: extremely unlikely, unlikely, unsure, likely, and extremely likely. To determine the factors that influence this response, random parameters ordered probit models are estimated to account for the likelihood that considerable unobserved heterogeneity is likely to be present in the data. The findings show that a wide range of socioeconomic factors affects people's likelihood of vehicle relinquishment in the presence of shared autonomous vehicles. Key among these are gender effects, generational elements, commuting patterns, and respondents' vehicle crash history and experiences. While people's opinions of shared autonomous vehicles are evolving with the continual introduction of new autonomous vehicle technologies and shifting travel behavior, the results of this study provide important initial insights into the likely effects of shared autonomous vehicles on household vehicle ownership.     

Structures of commitment in mode use: a comparison of Switzerland, Germany and Great Britain

Travellers commit themselves to particular behaviours through the ownership of cars and season tickets. They trade a large one-off payment for low or zero marginal cost at the point of use. It can be assumed that these commitments influence travel behaviour. To the knowledge of the authors there is no literature which addresses the choice between the commitment to the one or the other mode and its impacts on travel behaviour.The paper presents models using structural equation modelling to test a-priori hypotheses on the paths linking car-availability, season-ticket-ownership and modal usage. Modal usage is operationalised as the number of trips by car, public transport, or as the distances travelled by car or public transport. The models are based on three different surveys: Switzerland, Germany and Great Britain. The results confirm the dominance of car-availability, which drives the other variables, but the relationships are more complicated than generally assumed.     

Leisure travel in Europe and airline business models: A study of regional airports in Great Britain

Tourism and air transport are explicitly linked especially in the context of leisure traffic. This paper highlights this relationship by focusing on the impact of the three main airline business models (traditional scheduled, charter and low-cost) on regional airports using Britain as a case study. The panel data econometric results show that despite the current perception, low cost carriers are not the only ones to contribute significantly to airport aeronautical and non-aeronautical revenue. This observation has important policy implications and calls for transparency in airport subsidies as argued in the conclusion.     

The built environment and vehicle ownership modeling: Evidence from 32 diverse regions in the U.S.

Vehicle ownership is an important determinant of the travel demand forecasting process. Vehicle ownership models are used by policy makers to identify factors that affect vehicle miles traveled, and therefore address problems related to energy consumption, air pollution, and traffic congestion. For the conventional travel demand forecasting, it logically follows land use forecasting, before trip generation, which is commonly treated as step one. The most critical limitation of the vehicle ownership models, especially in the conventional process, is that they are often related mainly to sociodemographic variables, not so much to built environmental variables. In this study, by pooling regional household travel survey data from 32 diverse regions (almost 92,000 households) of the U.S., and by controlling for socio-demographic and the built environmental variables, we estimated a vehicle ownership model that contributes to the understanding of vehicle ownership and improves the accuracy of travel demand forecasts. Two main findings of this research are: 1) The number of vehicles owned by a household increases with socio-demographic variables and decreases with almost all of the built environmental variables. For the urban planning and design practices, this finding suggests that car shedding occurs as built environments become more dense, mixed, connected, and transit-served. 2) We used both count regression and discrete choice models, and the results suggest that count regression models have better predictive accuracy. The model developed in this study can be directly used for travel demand modeling and forecasting by metropolitan planning organizations.     

A dynamic hazard-based system of equations of vehicle ownership with endogenous long-term decision factors incorporating group decision making

The transportation system affects all aspects of our daily lives including relatively long-term decisions on work and home location choice and automobile ownership decisions. The interdependency existing among these three decisions jointly influences household mobility and overall travel patterns. Therefore, a dynamic modeling framework that can account for the effects of interdependencies between vehicle transaction behavior and residential and job location choices is highly desirable. These decisions are made in the household level while individuals’ decisions influence the overall outcome; therefore, it is also important to incorporate a group decision making process within such modeling frameworks.This study introduces a dynamic model for vehicle ownership, residential mobility, and employment relocation timing decisions. These decisions are modeled at the individual level and then sequentially aggregated to the household level if it is required. A hazard-based system of equations is formulated and applied in which work location and residential location changes are included as endogenous variables in the vehicle transaction model while other important factors such as land-use and built environment variables, household dynamics, and individuals’ socio-demographics are also considered.     

An examination of the factors that impact upon multiple vehicle ownership: The case of Dublin, Ireland

This paper examines the characteristics of households with multiple car ownership in Dublin, Ireland. Data from the 2006 Census of Ireland are analysed to ascertain the characteristics of these households. The analysis of multiple car ownership presented herein examines individual specific, transport availability, and household characteristics to provide an indication of the individuals most likely to have access to more than one vehicle. Understanding the characteristics of households with more than one car is important for many reasons, such as how policies for emissions reductions or pricing regimes might affect households. Ireland, like many countries, has recently launched a number of electric vehicle and car sharing schemes. Traditionally these schemes have been aimed at reducing multiple car ownership, therefore it is important to develop an understanding of the households that would most likely give up an extra car and use a car sharing scheme or an electric vehicle. Also from a sustainability point of view, greater levels of car ownership can result in unsustainable transport patterns.This paper examines the Census data using a multinomial logit regression model to determine the relationships between multiple car ownership levels and several household characteristics. The findings of the paper demonstrate that occupation, public transport availability and residential density all have an impact upon the decision to own more than one vehicle.     

Potential for electric vehicle adoption in Australia

Data from the New South Wales (NSW) Household Travel Survey (2014/15 NSW, T. f. (2014/15, 9/15/2016). SA3 Household Travel Survey (HTS). Retrieved from https://drive.google.com/open?id=0B12S3-OIR0hOT3oyYzJnMVp1UWs [Google Scholar]) was analyzed to determine the trip-by-trip range of automobile travel in NSW. The results show that 88% of trips were less than 30?km, which could readily be provided by electric vehicles, consuming a total of 18?GWh in electrical energy per weekday. Even if all electric vehicles were recharged from non-renewable coal-fired power plants, the greater efficiency of electric vehicles would result in a reduction of greenhouse gas emissions across NSW by 18% carbon dioxide equivalent (CO_2(eq))_. Additionally, we mapped the average state of charge distribution of the electric vehicles at key times during the day, indicating the maximum net load (for recharging) and/or available energy (for vehicle-to-grid services) across NSW. The results are consistent with other international studies and demonstrate the potential for wide scale electric vehicles adoption in Australia.     

Estimating emissions based on the integration of microscopic traffic simulation and vehicle dynamics model

This study proposes an integrated simulation approach, which consists of a microscopic traffic simulation model, a vehicle dynamics model, and an emission estimation model, in order to estimate emissions based on more reliable vehicle performance measures. The vehicle performance measures such as engine power and engine speed significantly relate to the amount of emissions, and road curvatures and inclinations are the core inputs affecting these vehicle performance measures. Therefore, providing reliable vehicle performance measures reflecting the road geometric attributes is critical for a reliable emission estimation. This study proposes to use the microscopic traffic simulation model for generating vehicle trajectories, which is advantageous in modeling various traffic situations, and the vehicle dynamics model for producing the vehicle performance measures based on the vehicle trajectories. Finally, the outputs from the vehicle dynamics model are fed into the emission estimation model to compute emission measures. This study conducted a case-study using two road sections, one is a hypothesized road section, including various curvatures and inclinations with regular variations, and the other is a Kesselberg road section, which is an actual geometry in Bayern, Germany. The emission measures are estimated in these case-study road sections using both an existing simulation approach and the proposed integrated simulation approach. The difference between these two emission estimation approaches is discussed in terms of the emission measures, including fuel consumption, nitrogen oxides, and particulate matters.     

The impact of local work and residential balance on vehicle miles traveled: A new direct approach

This paper introduces a new approach for explaining the effects of spatial competition for opportunities based on a cumulative opportunities measure of accessibility. We focus on the case of the labor market where some municipalities offer too few workplaces for their local population, forcing some of their residents to long drives. We apply this new accessibility measure to explain households' annual mileage in Switzerland using a Heckman model to account for carless households.We find that car travel demand is much greater in municipalities with a relative undersupply in the local labor market compared to a balanced or oversupplied local labor market. The results show that driving increases with greater distance to the labor market center. The model estimates allow policy makers and planners to quantify as a first assessment the expected average mileage in each municipality for new settlements and to identify municipalities with low expected annual mileage.     

Investigating household vehicle ownership,mode choice and trip sharing decisions using a combined revealed preference/stated preference Nested Logit model: case study in Bangkok Metropolitan Region

This study proposes a Nested Logit model to investigate household travel behaviour in respect to vehicle ownership, mode choice and trip sharing decisions. The model is analysed using revealed preference (RP) and stated preference (SP) data since a combined estimation of RP/SP data is an effective method of expressing complex travel behaviour and forecasting travel demand for new transport services. In the proposed model, the nesting structure has two levels. The upper level shows car ownership, motorcycle ownership, and no vehicle-ownership choices, and the lower level shows the mode choice combinations for two-traveller households. Trip sharing is considered as one of the mode-choice options in the model. The proposed model is analysed using data from the Bangkok Metropolitan Region. The analysis conducted informs that Central Business District (CBD) travel, long distance travel, household income, job status, age of travellers and presence of school children in households are key aspects in household travel decisions. Based on these aspects, households make important decisions on vehicle ownership, mode choice and trip sharing. In addition, this study reveals commuters’ hidden preferences for modes that are not in existence, in particular the Mass Rapid Transit System in the Bangkok Metropolitan Region due to be fully implemented in 2010.     

Cleaner vehicle buses in Winchester

This paper reports the results of a package of measures, contained within a Quality Bus Partnership, designed to reduce the environmental impact of the local bus fleet in Winchester. These measures were implemented by Hampshire County Council, Stagecoach Bus Company and Winchester City Council as part of the EU-sponsored CIVITAS MIRACLES project which ran from 2002 to 2006 and whose aims included reducing the environmental impact of transport at the local level while increasing urban accessibility. It follows on from a previous paper published in Transport Policy in 2007 looking at the success of measures implemented in Winchester to improve bus service quality and information.These implemented measures included the introduction of 13 new Euro III buses, re-powering 10 older buses from Euro I to Euro III standard, adding particulate traps to four Euro II buses and the demonstration of two different diesel/electric hybrid buses during two week-long trials in 2003 and 2004 along the Park and Ride route.In order to evaluate the effects of these measures, data was collected from the bus operator Stagecoach regarding their fleet of 59 vehicles in Winchester. This included their emission standard, reliability, average age and smoke test results. Emission modelling was carried out using a vehicle activity model on a key city centre street to assess emissions savings as a result of the implemented measures. In addition, two bus questionnaire surveys were carried out to assess passenger's views of the two diesel/electric hybrid buses used during the trials. Conclusions and recommendations have been made with regard to the environmental impact of the cleaner Winchester bus fleet and the contribution it has made to reducing emissions from motor vehicles in the Winchester central area.     

Privatisation and commercialisation: Changes in UK airport ownership patterns

This paper examines changes in airport ownership patterns with reference to UK municipal airports. The implications of commercialisation and privatisation are explored at a national level. General issues and impacts that may serve as a guide to policy makers worldwide are identified. The need for countries to have a strategic airports policy to guide development towards national economic and environmental goals is highlighted. The paper concludes that a uniform pattern of privatised airport ownership offers benefits from economic, policy and planning perspectives. © 1999 Elsevier Science Ltd. All rights reserved