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1.
Quantitative studies have revealed that changes to the number of cars owned by households are more likely to occur at the time of life events. However, causal explanations of such relationships are either absent or lacking evidence. To address this knowledge gap, this paper presents a qualitative study which enabled the development of a new conceptual framework to explain the process through which the number of cars owned by households changes over time. The framework emerged through an inductive analysis of 15 in-depth biographical interviews and was validated through a mixed methods survey of 184 households located in Bristol (UK). The following mechanisms of the process are identified: Life events alter roles, relationships, spatial contexts and lifestyle preferences. This can lead to a condition of stress which relates to a discrepancy between satisfaction with the current car ownership level and a more desirable alternative. Attempts to adjust to the new situation are made through processes of travel behaviour adaptation and consideration of whether the car ownership level ought to be altered. A propensity to change car ownership level can emerge from this. However, given the effort involved in taking action, households tend to resist making changes to their car ownership level in the short term. Action to change car ownership level is found to often be prompted by another external stimulus such as the receipt of a maintenance bill. A key message from the analysis is that changes in household car ownership level should be considered as the outcome of a continuous process of development over the life course, rather than as discrete decisions. 相似文献
2.
This article explores the stability of local vehicle ownership rates in Great Britain using the technique of spatial Markov chain analysis. Non-spatial Markov chain processes describe the transition of neighbourhoods through levels of ownership with no regard to their neighbourhood context. In reality however, how a neighbourhood transitions to different levels of ownership could be influenced by its neighbourhood context. A spatial Markov chain accounts for this context by estimating transition properties that are conditioned on the surrounding neighbourhood. These spatial Markov chain properties are estimated using a long run census time series from 1971 to 2011 of household vehicle ownership rates in Great Britain. These processes show that there is different behaviour in how neighbourhoods transition between levels of ownership depending on the context of their surrounding neighbours. The general finding is that the spatial Markov process will lead to a greater homogeneity in levels of ownership in each locality, with neighbourhoods surrounded by relatively low ownership neighbourhoods taking longer than a non-spatial Markov process would suggest to transition to higher levels, whilst neighbourhoods of high ownership surrounded by high ownership neighbourhoods take longer to transition to lower levels. This work corroborates Tobler's first law of geography “Everything is related to everything else, but near things are more related than distant things” but also provides practical guidance. Firstly, in modelling ownership, spatial effects need to be tested and when present, accounted for in the model formulation. Secondly, in a policy context, the surrounding neighbourhood situation is important, with neighbourhoods having a tendency towards homogeneity of ownership levels. This allows for the effective planning of transport provision for local services. Thirdly, vehicle ownership is often used as a proxy for the social and aspirational nature of an area and these results suggest that these properties will persist for a prolonged period, possibly perpetuating and exacerbating differentials in society. 相似文献
3.
This article investigates how young individuals access the regime of automobility. Instead of looking at the systemic nature of automobility, the article concentrates on its human component. Access to cars by young people in the greater Reykjavík area, and the shift in modal choice that occurs when they start driving, was investigated with a survey among high school students that yielded 553 answers. The results show that young residents in the capital area are fully aware of the costs of car-based automobility. Their near-universal move to cars when they enter driving age reflects the conditions of this regime. Yet they are also ambivalent about their position within the regime. While most previous studies of novice drivers have centred on road safety issues, this study shows the need to consider the cultural and social aspects of young people driving. This can lead to a deeper understanding of the modal shift that perpetuates car-based automobility, which is an important issue for transport planning. 相似文献
4.
A spatial analysis has been conducted in England, with the aim to examine the impact of car ownership and public transport usage on breast and cervical cancer screening coverage. District-level cancer screening coverage data (in proportions) and UK census data have been collected and linked. Their effects on cancer screening coverage were modelled by using both non-spatial and spatial models to control for spatial correlation.Significant spatial correlation has been observed and thus spatial model is preferred. It is found that increased car ownership is significantly associated with improved breast and cervical cancer screening coverage. Public transport usage is inversely associated with breast cancer screening coverage; but positively associated with cervical cancer screening. An area with higher median age is associated with higher screening coverage. The effects of other socio-economic factors such as deprivation and economic activity have also been explored with expected results. Some regional differences have been observed, possibly due to unobserved factors.Relevant transport and public health policies are thus required for improved coverage. While restricting access to cars may lead to various benefits in public health, it may also result in worse cancer screening uptake. It is thus recommended that careful consideration should be taken before implementing policy interventions. 相似文献
5.
Car ownership is generally considered an important variable in car travel behaviour research, but its specific role is often not well understood. Certain empirical studies consider car ownership as the dependent variable explained by the built environment, whereas other studies deem it to be one of the independent variables explaining car travel behaviour. This paper takes note of the dual influence car ownership has in explaining car travel behaviour by assuming that car ownership mediates the relationship between the built environment and car use. The relationship is estimated using a structural equation model since it accounts for mediating variables. This approach confirms the intermediary nature of car ownership. 相似文献
6.
Simon Blainey 《Journal of Transport Geography》2010,18(1):153-165
This paper details models which have been developed to forecast the total number of trips made from local rail stations in England and Wales over a one year period. The use of multiple linear regression and geographically weighted regression in calibration are compared, with both explaining over 75% of the variation in the observed data. The latter technique has not previously been used in rail demand modelling, and allows significant spatial variations in the effect of independent variables to be identified and mapped. A number of catchment definition methods are investigated, as is the inclusion of a wide range of demographic and service related explanatory variables. The models developed are used to forecast usage at stations on the recently opened Ebbw Vale branch line in South Wales and these predictions are compared to initial usage figures. 相似文献
7.
Governments in many countries are experimenting with alternative methods for reducing car use, including congestion charges, increased fuel taxation, and improved public transport. This paper raises another possibility. Not only could public transport be marketed as an alternative to the private car, but through targeted propaganda, the automobile could be de-marketed as a status symbol and a convenient accessory of modern life. In contrast with other public information campaigns, de-marketing would focus on people's self-image rather than their sense of public duty.The authors draw on established theory in putting forward alternative themes aimed at particular categories of user and particular categories of journey, and briefly consider the strengths and weaknesses of each approach. Peer group pressure could be an important factor in helping to change attitudes among potential car users at the opinion-forming stage during their life cycle. The agencies best positioned to deliver an effective national campaign are public transport corporations, local authorities, health organisations, and environmental lobby groups; a co-ordinated approach could bring about a modest contribution towards travel reduction at a relatively low cost. 相似文献
8.
Subhashini Muthukrishnan 《Transport Policy》2010,17(6):398-408
We present a simple model to study the welfare effects of a shift from ownership to usage taxes for cars. We consider a model in which a single representative consumer derives utility from consuming two goods—consumption of motor vehicle kilometers, and an aggregate consumption good treated as numeraire. We characterize the optimal consumption of car kilometers by a representative car user and find that a shift from ownership towards usage taxes is not necessarily welfare-improving: while a revenue-neutral shift makes the representative car user worse off; a utility-neutral shift leads to a significant loss of revenue to the government. An empirical analysis based on Singapore data is also consistent with our theoretical results. 相似文献
9.
This paper explores insights about marginal airport costs that can be gained by analysing labour inputs and their variability. Based on hourly cost and traffic data for the airport of Helsinki, a multivariate time series approach is used incorporating correlated error terms to account for random shocks such as delays. We found for most airport services a linear relationship between labour input and aircraft movements, except for producing passenger services for international departing flights where a cubic cost relationship was estimated. The findings are comparable with earlier studies for US airports. 相似文献
10.
Eunjin Choi 《International Journal of Sustainable Transportation》2017,11(6):395-405
The models based on vehicle speed have been used to estimate fuel consumption and CO2 emissions. However, these models could not properly estimate the change in fuel consumption and CO2 emissions as the speed changes. As for the alternative method, people try to consider using acceleration instead of speed. Although acceleration has been seriously considered, determining critical aggressive acceleration value in relation to fuel consumption and CO2 emissions is difficult to find. In this study, evaluation models of fuel consumption were developed using instantaneous acceleration, and we defined the critical aggressive acceleration values for different states of the vehicle from the viewpoints of fuel consumption and emissions. We used a mid-sized Liquefied Petroleum Gas (LPG) passenger car and obtained instantaneous data from a digital tachograph installed in the car while it accelerates. We developed two fuel consumption models and found critical aggressive accelerations, respectively: a model of starting vehicle that measures range of speed required to overcome the inertia during acceleration from stop state, and the other model for the driving state. We used Classification and Regression Tree (CART) analysis to find the critical aggressive accelerations at which the increments of fuel consumption change abruptly. As a result, the critical aggressive accelerations causing abrupt change in the increments of fuel consumption were found to be 2.598 m/s2 for the starting of vehicles and 1.4705 m/s2 when driving them. We also found that the increments of fuel consumption can be explained through quadratic and exponential functions with instantaneous acceleration. 相似文献
11.
David Gillen 《Journal of Air Transport Management》2011,17(1):3-13
This presentation examines the evolution of airport governance from public utility to modern business. I also briefly look at airport regulation and in this context ask the questions, do airports need to be regulated and if so, why? I consider the new thinking on two-sided platforms and examine whether this may be the new way of thinking about governance. In judging governance structures and regulation, I argue that dynamic efficiency has been underemphasized in the debate over privatization and that airline deregulation has been most important in shifting the balance of power between airlines and airports. 相似文献
12.
《Journal of Air Transport Management》2006,12(2):63-75
Most countries require substantial domestic equity ownership of designated national airlines, yet changes in international capital markets have significantly altered the way control rights associated with equity are exercised. We argue that in a context of aviation deregulation and liberalization, a new generation of aviation financiers has appeared whose incentives and competence for control diminishes the relevance of the nationality provisions contained in most bilateral agreements. The paper describes recent developments in ownership and control and its impact on airline management. 相似文献
13.
Benefits of shift from car to active transport 总被引:1,自引:0,他引:1
There is a growing awareness that significant benefits for our health and environment could be achieved by reducing our use of cars and shifting instead to active transport, i.e. walking and bicycling. The present article presents an estimate of the health impacts due to a shift from car to bicycling or walking, by evaluating four effects: the change in exposure to ambient air pollution for the individuals who change their transportation mode, their health benefit, the health benefit for the general population due to reduced pollution and the risk of accidents. We consider only mortality in detail, but at the end of the paper we also cite costs for other impacts, especially noise and congestion. For the dispersion of air pollution from cars we use results of the Transport phase of the ExternE project series and derive general results that can be applied in different regions. We calculate the health benefits of bicycling and walking based on the most recent review by the World Health Organization. For a driver who switches to bicycling for a commute of 5 km (one way) 5 days/week 46 weeks/yr the health benefit from the physical activity is worth about 1300 €/yr, and in a large city (>500,000) the value of the associated reduction of air pollution is on the order of 30 €/yr. For the individual who makes the switch, the change in air pollution exposure and dose implies a loss of about 20 €/yr under our standard scenario but that is highly variable with details of the trajectories and could even have the opposite sign. The results for walking are similar. The increased accident risk for bicyclists is extremely dependent on the local context; data for Paris and Amsterdam imply that the loss due to fatal accidents is at least an order of magnitude smaller than the health benefit of the physical activity. An analysis of the uncertainties shows that the general conclusion about the order of magnitude of these effects is robust. The results can be used for cost-benefit analysis of programs or projects to increase active transport, provided one can estimate the number of individuals who make a mode shift. 相似文献
14.
Mike G. Tsionas Anna A. Merika 《Transportation Research Part E: Logistics and Transportation Review》2012,48(4):843-852
This paper addresses the issue of ownership structure and corporate performance. It employs a sample of 107 internationally listed shipping firms (about 60% of the total) and examines their financial data and ownership concentration for the year 2009. Ownership is treated as an endogenous variable and GMM estimation is used incorporating the significant advance provided by Lewbel (1997). Empirical results suggest that concentrated ownership is positively and strongly associated with better firm performance in the shipping industry. Furthermore, this paper offers evidence on ownership concentration and shows that despite the different corporate governance settings, ownership structures are quite similar in shipping. 相似文献
15.
Evren Özkaya Pınar Keskinocak V. Roshan Joseph Ryan Weight 《Transportation Research Part E: Logistics and Transportation Review》2010,46(5):667-682
In this paper, we present a regression-based methodology that can estimate the Less-than-Truckload (LTL) market rates with high reliability using an extensive database of historical shipments from continental United States. Our model successfully combines the quantitative data with qualitative market knowledge to produce better LTL market rate estimates which can be used in benchmarking studies allowing carriers and shippers to identify cost saving opportunities. We identify the main drivers of LTL pricing and reveal the effects of certain industry practices on the final market rates. 相似文献
16.
We analyse why deregulation resulted in a temporary strong reduction in prices in Sweden, whereas in Norway the prices did not change significantly. SAS and Linjeflyg merged when the Swedish market was deregulated, whereas attempts to merge SAS and Braathens SAFE did not succeed. Upon deregulation in Sweden some of the carriers operating charter markets or regional secondary routes decided to enter the main routes. This put pressure on prices. Similar entries did not take place in the Norwegian market. We analyse whether the duopoly between SAS and Braathens SAFE is characterised by tacit collusion. 相似文献
17.
Zhijia Tan 《Transportation Research Part E: Logistics and Transportation Review》2012,48(6):1080-1092
This paper considers the problem of how to select the toll and capacity levels of a new toll road added onto an existing network with a single link. The existing network has various ownership regimes: free, public or private owned toll road. The effects of the ownership regime of the existing network on the capacity and toll selections of the add-on toll road, the efficiency of the whole network in the sense of total social benefit, and the investment incentives of the government to develop the new road are investigated when the traffic demand is elastic or inelastic. 相似文献
18.
This paper develops the model and methodology to estimate the marginal external cost of urban road transport, which is necessary for analysing optimal urban transport prices. Four major marginal external costs analysed in this paper include the marginal external costs for congestion, air pollution, road accidents and noise. The paper estimates the marginal external costs for cars and buses in peak and off-peak periods for Delhi urban agglomeration for the year 2005. 相似文献
19.
如今,航空网络服务公司(AirlineNetworkServices,ANS)的覆盖范围正在快速扩大。2010年12月在多伦多以及蒙特利尔开设了分支机构后,这家位于纽约的销售总代理(GSA)于2011年2月在美国波特兰也开设了办事机构,如今正在准备进入南美洲。按照ANS的创始人和CEOJensTubbesing的说法,2011年5月底将在巴西圣保罗机场运营分支机构。 相似文献
20.
This paper examines the policy processes behind Singapore's car quotas. The policy, when filtered through the market mechanism, had a number of unintended consequences. The public's unhappiness with certain features and ‘loopholes’ of the system resulted in many changes to the rules. The effects of recent measures to curb speculation on quota premiums are evaluated. Problems with Singapore's Weekend Car Scheme are also discussed. The lesson for transport policy makers elsewhere is that in attempting to deal with the road congestion problem through car ownership policies, an asset market for vehicles should be taken into account. 相似文献