Volatility of car ownership, commuting mode and time in the UK

This paper has two objectives: to examine the volatility of travel behaviour over time and consider the factors explaining this volatility; and to estimate the factors determining car ownership and commuting by car. The analysis is based on observations of individuals and households over a period of up to 11 years obtained from the British Household Panel Survey (BHPS). Changes in car ownership, commuting mode and commuting time over a period of years for the same individuals/households are examined to determine the extent to which these change from year-to-year. This volatility of individual behaviour is a measure of the ease of change or adaptation. If behaviour changes easily, policy measures are likely to have a stronger and more rapid effect than if there is more resistance to change. The changes are “explained” in terms of factors such as moving house, changing job and employment status. The factors determining car ownership and commuting by car are analysed using a dynamic panel-data models.     

Substitution between working at home and out-of-home: The role of ICT and commuting costs

This paper analyzes the trade-off between working at home and out-of-home, ICT and commuting time. To this end, we develop a microeconomic demand system, which explicitly incorporates both time and income constraints. Commuting time is considered as the price to be paid for working out-of-home and a decrease in earnings as the price for working at home. For the latter, we find that working at home leads to a (marginally significant) reduction of the wage rate of about 19%, but this gap largely disappears when ICT is used for at home work. To examine the relation between out-of-home and at home work empirically, we estimate a translog indirect utility function, from which we are able to estimate substitution and price elasticities between working at home and out-of-home for The Netherlands. The results show that changes in ICT and commuting time display rather weak substitution effects on working out-of-home and at home, respectively. Moreover, individual characteristics – especially age and education – seem to be more important for the choice between working at home and out-of-home than ICT availability or commuting time.     

Household-level commuting mode choices,car allocation and car ownership level choices of two-worker households: the case of the city of Toronto

The paper presents a comprehensive investigation on household level commuting mode, car allocation and car ownership level choices of two-worker households in the City of Toronto. A joint econometric model and a household travel survey dataset are used for empirical investigations. Empirical models reveal that significant substitution patterns exist between auto driving and all other mode choices in two-worker households. It is revealed that, female commuters do not prefer auto driving, but in case of a one car (and two commuters with driving licenses) household, a female commuter gets more preference for auto driving option than the male commuter. Reverse commuting (commuting in opposite direction of home to central business district) plays a critical role on household level car allocation choices and in defining the stability of commuting behaviour of two-worker households. Two worker households in higher income zones and with longer commuting distances tend to have higher car ownership levels than others. However, higher transit accessibility to jobs reduces household car ownership levels. The study reveals that both increasing two worker households and reverse commuting would increase dependency on private car for commuting.     

The accessibility of railway stations: the role of the bicycle in The Netherlands

The market potential of railway services depends on the quality of the total chain from residence to place of activity. In The Netherlands where natural conditions and infrastructure are conducive, the bicycle is a potentially attractive access mode for railways since it allows travellers to avoid waiting at bus, metro or tram stops. Especially at the home end the bicycle appears to play a large role as an access mode with a share of 35%. At the activity end the share is much shorter. Implications are discussed for policies aiming at increasing the share of multimodal trips. Also physical planning implications are considered.     

The impact of weather conditions on bikeshare trips in Washington,DC

Bicycle usage can be affected by colder weather, precipitation, and excessive heat. The research presented here analyzes the effect of weather on the use of the Washington, DC, bikeshare system, exploiting a dataset of all trips made on the system. Hourly weather data, including temperature, rainfall, snow, wind, fog, and humidity levels are linked to hourly usage data. Statistical models linking both number of users and duration of use are estimated. Further, we evaluate trips from bikeshare stations within one quarter mile of Metro (subway) stations at times when Metro is operating. This allows us to determine whether Metro serves as a back-up option when weather conditions are unfavorable for bicycling. Results show that cold temperatures, rain, and high humidity levels reduce both the likelihood of using bikeshare and the duration of trips. Trips taken from bikeshare stations proximate to Metro stations are affected more by rain than trips not proximate to Metro stations and less likely when it is dark. This information is useful for understanding bicycling behavior and also for those planning bikeshare systems in other cities.     

The effect of socio-economic factors on the value of time in commuting to work

It is important to specify accurately the dollar value assigned to time savings, since up to eighty percent of the benefits estimated to accrue from improvements in transportation systems are associated with savings in travel time. In this paper the economic theory of consumer choice is utilized to structure a model that is used to estimate how Value of Time (VOT) measures vary with community-related variables.Parameters for this theoretical model are empirically estimated using data from transportation surveys conducted in Ithaca and Syracuse, New York and Amherst, Massachusetts. The results confirm the validity of the theoretical model and suggest that leisure time, travel cost, and household income level, as well as community population, are important determinants of the marginal value of time. These models are particularly suited for transferring data results obtained in one community to another, thereby saving survey costs, since the resulting VOT estimates are based solely on underlying socio-economic variables and community characteristics that are known for most localities. The methodology is also useful for estimating different VDT's for particular population subgroups, like the elderly, which may be the focus of a particular transportation project.     

The social context of informal commuting: Slugs, strangers and structuration

Despite considerable interest in the role of social interactions and social context on transportation, there have been very few attempts to explore specific cases of social interaction influencing transportation systems. This paper explores the social practice of slugging, an informal system of carpooling in the Washington, DC area. Slugging emerged in response to the establishment of Virginia’s High Occupancy Vehicle (HOV) lanes in the early 1970s, as single drivers picked up riders alongside the road (slugs) in order to meet the requirements for driving in the less congested HOV lanes. Drawing on the work of sociologist Anthony Giddens, as well as the sociological insights of Georg Simmel and Stanley Milgram, we suggest that the practice of slugging highlights the processes of institutionalization and structuration. This paper details how the region’s mass transportation policies and urban culture have combined to result in an institutionalized practice with particular norms and logics of behavior. We conclude that looking at specific cases where social context has affected transportation, like slugging, could provide useful insights on the impact of social context on transportation policies and systems.     

Bicycle in Shanghai: Movement patterns,cyclist attitudes and the impact of traffic separation

Transportation demand continues to grow at an even faster rate than the economies of Chinese cities, placing increasing pressure on a limited road network. In certain cities of the more highly developed coastal plains, the bicycle assumed a dominant role in urban transport in the 1980s, a position maintained in the 1990s. In Shanghai, the bicycle continues to play a dominant role, although policies favour a switch to public transport. In the present paper, cyclist attitudes toward public transport policies were probed with a pilot questionnaire at two important central destinations. An important example of current policies with regard to bicycles involves the creation of separate networks for motorized and non-motorized modes. A pilot scheme for eventual application over a very large area was recently introduced in the central area. We report on the traffic volumes by mode and street before and after its implementation in 1999. Both bicycle and car volumes diminished in the central area, although the decrease was greater for bicycles. On the other hand, interviewed cyclists expressed resistance to various incentives to use public transport. The question raised here is whether the planned increase in public transport share of total intracity travel can be achieved without disincentives to use the bicycle.     

Suburbanization of jobs and the journey to work: A submarket analysis of commuting in the San Francisco bay area

Inrecent years, a debate has brewed over whether the decentralization of employment has been beneficial from a regional standpoint. In this article, we focus on one aspect of the debate: how the relocation of office workers from a downtown to a suburban location affects commuting patterns and mode choice. From a survey of 320 former downtown San Francisco workers who now work in the suburbs, we found that the average distance traveled remained essentially unchanged and that the average commuting speed increased. The most dramatic change, however, was the switch from public transit to drive-alone commuting. In the aggregate, we estimate that the change in job location was associated with nearly a threefold increase in vehicle miles traveled to work. While from a personal standpoint, employees seemed better off since they got to work faster and more comfortably, from a larger social and environmental perspective, the costs could be significant. More detailed analyses of commuter submarkets revealed that the transportation impacts vary considerably depending on whether the original residence was in the suburbs or central city and whether relocated workers had moved their residences in recent years. In general, those who remained in San Francisco and became reverse commuters were worst off whereas those who moved their residences out of the city were much better off in terms of job access. The article concludes that road pricing would be the best way to force motorists to internalize the external costs of increased drive-alone commuting. Second-best options would be to introduce development impact fees or employer-based trip reduction regulations.     

Influence of the residential and work environment on car use in dual-earner households

This paper analyses whether the decision to commute by car is influenced by built environment characteristics of residential neighbourhoods and, more especially, of work locations, taking into account interdependencies between household partners. It shows that the residential environment only affects car use among single-earners. Conversely, for all commuters, but in particular for dual-earners, characteristics of the work location affect whether they commute by car. Even in dual-earner households with two cars, work environment plays a role. We found that in cases of dual-earners with only one car, the partners with the longest commuting distances and the lowest density work locations are most likely to commute by car. Moreover, in households with young children, men are more inclined to leave the car at home. Other features relating to work also affect car commuting, including work flexibility and, especially, possession of a company car. We conclude that future policies aimed at reducing car use should place greater focus on work factors.     

Changes in level of household car ownership: the role of life events and spatial context

Recent longitudinal studies of household car ownership have examined factors associated with increases and decreases in car ownership level. The contribution of this panel data analysis is to identify the predictors of different types of car ownership level change (zero to one car, one to two cars and vice versa) and demonstrate that these are quite different in nature. The study develops a large scale data set (n = 19,334), drawing on the first two waves (2009–2011) of the UK Household Longitudinal Study (UKHLS). This has enabled the generation of a comprehensive set of life event and spatial context variables. Changes to composition of households (people arriving and leaving) and to driving licence availability are the strongest predictors of car ownership level changes, followed by employment status and income changes. Households were found to be more likely to relinquish cars in association with an income reduction than they were to acquire cars in association with an income gain. This may be attributed to the economic recession of the time. The effect of having children differs according to car ownership state with it increasing the probability of acquiring a car for non-car owners and increasing the probability of relinquishing a car for two car owners. Sensitivity to spatial context is demonstrated by poorer access to public transport predicting higher probability of a non-car owning household acquiring a car and lower probability of a one-car owning household relinquishing a car. While previous panel studies have had to rely on comparatively small samples, the large scale nature of the UKHLS has provided robust and comprehensive evidence of the factors that determine different car ownership level changes.     

The impact of transportation demand management policies on commuting to college facilities: A case study at the University of Trieste,Italy

Universities, like other types of public and private institutions, when located in a city, have both positive and negative impacts on the area where they are situated. On the one hand, they contribute to the prestige of the area; on the other hand, they are large generators/attractors of traffic. The ability to successfully balance the pros and cons of the urban location of these large traffic-generating institutions is crucial for their success and for the livability of the city. In this paper this issue has been analyzed selecting as a representative case the University of Trieste.The aim of the research is to understand: (a) how mode choice decisions are made by the teaching and administrative staff and by the students at the various locations where academic activities take place, and (b) how they would be affected by 8 different transport management policies. It is found that changing the parking regulations (via the annual permit cost, the hourly parking fee, the number of parking spaces and the location of the parking lots) greatly influences mode choice in favor of bus use, especially for teaching and administrative staff and in the suburban locations. The students would be impacted by such changes only if an hourly parking tariff is introduced. The alternative approach of fully subsidizing the bus services would also have a large impact on bus ridership, affecting the mode choice in particular of the teaching staff and in the main university suburban sites.Since the implementation of these bus-favoring policies could face the opposition either of the university staff or of the bus company, two more balanced policy mixes were tested: the first one, increasing parking price and imposing new parking restrictions, would increase bus ridership by 19%; the second one, reducing both bus and parking subsidies, would increase bus ridership by 13%.     

Accelerating the transformation to a low carbon passenger transport system: The role of car purchase taxes,feebates, road taxes and scrappage incentives in the UK

The transition to a low carbon transport world requires a host of demand and supply policies to be developed and deployed. Pricing and taxation of vehicle ownership plays a major role, as it affects purchasing behavior, overall ownership and use of vehicles. There is a lack in robust assessments of the life cycle energy and environmental effects of a number of key car pricing and taxation instruments, including graded purchase taxes, vehicle excise duties and vehicle scrappage incentives. This paper aims to fill this gap by exploring which type of vehicle taxation accelerates fuel, technology and purchasing behavioral transitions the fastest with (i) most tailpipe and life cycle greenhouse gas emissions savings, (ii) potential revenue neutrality for the Treasury and (iii) no adverse effects on car ownership and use.The UK Transport Carbon Model was developed further and used to assess long term scenarios of low carbon fiscal policies and their effects on transport demand, vehicle stock evolution, life cycle greenhouse gas emissions in the UK. The modeling results suggest that policy choice, design and timing can play crucial roles in meeting multiple policy goals. Both CO₂ grading and tightening of CO₂ limits over time are crucial in achieving the transition to low carbon mobility. Of the policy scenarios investigated here the more ambitious and complex car purchase tax and feebate policies are most effective in accelerating low carbon technology uptake, reducing life cycle greenhouse gas emissions and, if designed carefully, can avoid overburdening consumers with ever more taxation whilst ensuring revenue neutrality. Highly graduated road taxes (or VED) can also be successful in reducing emissions; but while they can provide handy revenue streams to governments that could be recycled in accompanying low carbon measures they are likely to face opposition by the driving population and car lobby groups. Scrappage schemes are found to save little carbon and may even increase emissions on a life cycle basis.The main policy implication of this work is that in order to reduce both direct and indirect greenhouse gas emissions from transport governments should focus on designing incentive schemes with strong up-front price signals that reward ‘low carbon’ and penalize ‘high carbon’. Policy instruments should also be subject to early scrutiny of the longer term impacts on government revenue and pay attention to the need for flanking policies to boost these revenues and maintain the marginal cost of driving.     

Exploring public bicycle network structure based on complex network theory and shortest path analysis: the public bicycle system in Yixing,China

A well-functioning public bicycle system relates not only to its mode of operation, vehicle allocation, rental station layout and vehicle leasing configuration, but also the bicycle network structure and its formation. However, the latter aspects have been widely overlooked in China. Here, we help to further attract more researchers to conduct relevant studies and make suggestions for the development of public bicycle transport in many small and medium-sized cities across the world. We demonstrate how to explore the public bicycle network structure of a county-level Chinese city – Yixing – known for its clay ware and tourism. We show that complex network theory and shortest path analysis technology are useful in characterizing the public bicycle network structure, in aspects such as network topology, the spatial distribution of sub-networks and traffic flows. Finally, the paper proposes relevant urban planning strategies.     

Car today,gone tomorrow: The ephemeral car in low-income,immigrant and minority families

Most transportation research in the United States uses cross-sectional, “snapshot” data to understand levels of car access. Might this cross-sectional approach mask considerable variation over time and within households? We use a panel dataset, the Panel Study of Income Dynamics (PSID), for the years 1999–2011 to test this question. We find that for most families, being “carless” is a temporary condition. While 13 % of families in the US are carless in any given year, only 5 % of families are carless for all seven waves of data we examine in the PSID. We also find that poor families, immigrants, and people of color (particularly, blacks) are considerably more likely to transition into and out car ownership frequently and are less likely to have a car in any survey year than are non-poor families, the US-born, and whites.     

The growing gap in pedestrian and cyclist fatality rates between the United States and the United Kingdom,Germany, Denmark,and the Netherlands, 1990–2018

ABSTRACT

Using official national data for each country, this article calculates trends in walking and cycling fatalities per capita and per km in the USA, the UK, Germany, the Netherlands, and Denmark. From 1990 to 2018, pedestrian fatalities per capita fell by 23% in the USA vs. 66%–80% in the other countries; cyclist fatalities per capita fell by 22% in the USA vs. 55%–68% in the other countries. In 2018, pedestrian fatality rates per km in the USA were 5–10 times higher than in the other four countries; cyclist fatality rates per km in the USA were 4–7 times higher. The gap in walking and cycling fatality rates between the USA and the other countries increased over the entire 28-year period, but especially from 2010 to 2018. Over that 8-year period, per-capita fatality rates in the USA rose by 19% for pedestrians and 11% for cyclists; per-km fatality rates rose by 17% for pedestrians and 33% for cyclists. By comparison, fatality rates either fell or remained stable in the four European countries. We reviewed the relevant literature to identify factors that might help explain the much lower walking and cycling fatality rates in Europe compared to the USA. Possible explanatory factors include better walking and cycling infrastructure; lower urban speed limits; fewer vehicle km travelled; smaller and less powerful personal motor vehicles; and better traffic training, testing, and enforcement of traffic regulations. We recommend that the USA consider implementing an integrated package of mutually reinforcing safety measures such as those that have been successfully implemented in the Netherlands, Denmark, and Germany to reduce pedestrian and cyclist fatality rates.