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1.
Random coefficient models such as mixed logit are increasingly being used to allow for random heterogeneity in willingness
to pay (WTP) measures. In the most commonly used specifications, the distribution of WTP for an attribute is derived from
the distribution of the ratio of individual coefficients. Since the cost coefficient enters the denominator, its distribution
plays a major role in the distribution of WTP. Depending on the choice of distribution for the cost coefficient, and its implied
range, the distribution of WTP may or may not have finite moments. In this paper, we identify a criterion to determine whether,
with a given distribution for the cost coefficient, the distribution of WTP has finite moments. Using this criterion, we show
that some popular distributions used for the cost coefficient in random coefficient models, including normal, truncated normal,
uniform and triangular, imply infinite moments for the distribution of WTP, even if truncated or bounded at zero. We also
point out that relying on simulation approaches to obtain moments of WTP from the estimated distribution of the cost and attribute
coefficients can mask the issue by giving finite moments when the true ones are infinite. 相似文献
2.
There is a significant body of evidence from both disaggregate choice modelling literature and practical travel demand forecasting that the responsiveness to cost and possibly to time diminishes with journey length. This has, in Britain at least, been termed ‘Cost Damping’, and is recognised in guidance issued by the UK Department for Transport. However, the consistency of the effect across modes and data types has not been established. Cost damping, if it exists, affects both the forecasting of demand and our understanding of behaviour. This paper aims to investigate the evidence for cost and time damping in rail demand using aggregate rail ticket sales data. The rail ticket sales data in Britain has, for many years, formed the basis of analysis of a wide range of impacts of rail demand. It records the number of tickets sold between station pairs, and it is generally felt to provide a reasonably accurate reflection of travel demand. However, the consistency of these direct demand models with choice modelling and highway demand model structures has not been investigated. Rail direct demand models estimated by ticket sales data indicate only slight variation in the fare elasticity with distance, as is evidenced in the largest meta-analysis of price elasticities conducted to date (Wardman in J Transp Econ Policy 48(3):367–384, 2014). This study of UK elasticities shows strong variation between urban and inter-urban trips, presumably a segmentation at least in part by purpose, but less remaining variation by trip length. A lack of variation by length supports the hypothesis of cost damping, because constant cost sensitivity would imply that fare elasticity would increase strongly with distance, because of the increasing impact of higher fares at longer distances. In this paper we indicate that rail direct demand models have some consistency of behavioural paradigm with utility based choice models used in highway planning. We go on to use rail demand data to estimate time and fare elasticities in the context of various cost damping functions. Our empirical contribution is to estimate time elasticities on a basis directly comparable with cost elasticities and to show that the phenomenon of cost damping is strongly present in ticket sales data. This finding implies that cost damping should be included in models intended for multimodal analysis, which may otherwise give incorrect predictions. 相似文献
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Transportation - The value of travel time (VTT) can be said to be the most important number in transport economics, and its estimation has been the topic of extensive academic and applied work.... 相似文献
5.
Transportation - Stated choice surveys have established themselves as the preferred approach for value of travel time elicitation with the help of choice models. However, major differences exist in... 相似文献
6.
This paper presents the results of a major before-and-after study carried out to establish the short term effects of the removal of a severe bottleneck in the road network around Amsterdam. An important focus in the study was on measuring changes in the timing of travel, as well as changes in route choice, mode choice, destination choice and frequency of travel. The results of the study indicated that, in the short run, there was little or no change in mode choice, nor was there significant emergence of new induced trips. On the other hand, large shifts in time of travel as well as route choice were reported, emphasising the importance of alterations to the timing and routes of existing trips when congestion is relieved, and the need to consider the benefits these bring in evaluating the impact of any road investment. 相似文献
7.
Andrew Daly Stephane Hess Bhanu Patruni Dimitris Potoglou Charlene Rohr 《Transportation》2012,39(2):267-297
There is growing interest in the use of models that recognise the role of individuals’ attitudes and perceptions in choice
behaviour. Rather than relying on simple linear approaches or a potentially bias-inducing deterministic approach based on
incorporating stated attitudinal indicators directly in the choice model, researchers have recently recognised the latent
nature of attitudes. The uptake of such latent attitude models in applied work has however been slow, while a number of overly
simplistic assumptions are also commonly made. In this article, we present an application of jointly estimated attitudinal
and choice models to a real-world transport study, looking at the role of latent attitudes in a rail travel context. Our results
show the impact that concern with privacy, liberty and security, and distrust of business, technology and authority have on
the desire for rail travel in the face of increased security measures, as well as for universal security checks. Alongside
demonstrating the applicability of the model in applied work, we also address a number of theoretical issues. We first show
the equivalence of two different normalisations discussed in the literature. Unlike many other latent attitude studies, we
explicitly recognise the repeated choice nature of the data. Finally, the main methodological contribution comes in replacing
the typically used continuous model for attitudinal response by an ordered logit structure which more correctly accounts for
the ordinal nature of the indicators. 相似文献
8.
Andrew Daly 《Transportation Research Part B: Methodological》1982,16(1):5-15
The paper presents a family of disaggregate choice models, which are shown to be equivalent to many of the aggregate models commonly used in planning studies. A brief summary is given of the method that has been developed for estimating the parameters of these models. A generalisation is then introduced in which variables representing the attractiveness in terms of size or quantity of each alternative are allowed to enter the model. It is shown that the form in which these variables enter the model requires a more general estimation algorithm than is commonly used, and such an algorithm is presented. A series of practical tests of the new algorithm is described. 相似文献
9.
In most developed countries motorized transportation is the dominant form of travel for long and short journeys. Transport-related
physical activity (TPA), however, is advocated as an appropriate transport mode for traveling short distances. The purpose
of this study is to explore the associations between private automobile availability, overall physical activity levels, and
TPA engagement in the adult population. A population-representative telephone survey assessed socio-demographics, private
automobile availability, overall physical activity levels, and travel to place of work/study and the convenience shop with
an adult sample (n = 2,000) residing in North Shore City, Auckland, New Zealand in April 2005. The majority of respondents reported unrestricted
(80%) or frequent (12%) private automobile availability. After controlling for covariates, binary logistic regression analyses
revealed those with no private automobile available were less likely to be classified as sufficiently active for health benefits
when compared to respondents with unrestricted private automobile availability. However, this finding was based on a small
minority (4%). Also, those reporting no private automobile availability were more likely to walk or cycle to place of employment
and the convenience shop when compared to those with unrestricted private automobile availability. Similar to other self-report
travel and physical activity survey tools, the questionnaire used potentially did not adequately capture TPA engagement. Future
TPA research needs to incorporate objective measures to address this issue.
相似文献
Hannah M. BadlandEmail: |
10.
Without questioning the fact that to achieve efficiency emitters should pay for the true costs of their actions (a core principle of economic policies such as pollution taxes), we find sufficient evidence in the literature to demonstrate that many other policy instruments can be used in combination with taxes and permits to ensure that the transport needs of the present generation can be met without compromising the ability of future generations to meet any needs of their own.The policies and policy aspects considered in this paper broadly fall into three categories: physical policies, soft policies, and knowledge policies. All three aim to bring about changes in consumers’ and firms’ behaviour, but in different ways. The first category includes policies with a physical infrastructure element: public transport, land use, walking and cycling, road construction, and freight transport. We also consider the particular challenges for mobility in developing countries, and how these may be addressed. Soft policies, on the other hand, are non-tangible aiming to bring about behavioural change by informing actors about the consequences of their transport choices, and potentially persuading them to change their behaviour. These measures include car sharing and car pooling, teleworking and teleshopping, eco-driving, as well as general information and advertising campaigns. Finally, knowledge policies emphasise the important role of investment in research and development for a sustainable model of mobility for the future.The main findings can be summarised as follows.