The Distribution of Individual Values of Time: An Empirical Study Using Stated Preference Data

This paper reports the findings of further work undertaken on the Stated Preference (SP) data collected as part of the Department of Transport's Value of Time Project. The latter study estimated values of time in a variety of different circumstances and for a number of modes of travel and also examined how the value of time varied according to socio-economic factors. Although values of time were allowed to vary across individuals by segmenting the data according to socio-economic factors, the SP data permits the estimation of values of time at the individual level whereupon a distribution of individual values can be obtained. The Department of Transport expressed some interest in what information could be provided by the SP data about the distribution of values of in-vehicle time across individuals. Individual values of in-vehicle time have been estimated for each of the five SP experiments which had previously been conducted to obtain a distribution for each survey context and also pooled across surveys to derive a population distribution. The problems of estimating values at the individual level with the SP data available are considered and the findings are compared with the average values previously derived in the Value of Time Study. How these individual values of time vary with socio-economic factors is also considered

The Effect of Rail Journey Time Improvements: Some Results and Lessons of British Experience Relevant to High Speed Rail Forecasting.

This paper discusses the British experience of forecasting the effect of journey time reductions on the demand for rail travel. Its purpose is to discuss results and methodologies from the British context which may be appropriate to other contexts, and particularly to forecasting the demand for new high speed rail services. Two areas of research are selected for discussion: aggregate econometric models of rail demand and Stated Preference choice models. It is concluded that the results derived from one context may not be as transferable as one might wish to some other situation and that it is important to obtain a better understanding of the factors influencing journey time elasticities. Both of the demand analysis methodologies discussed could contribute to an improved understanding whilst an attraction of the Stated Preference approach is that it lessens the need to transfer results from one context to another

Disaggregate Urban Mode Choice Models: A Review of British Evidence with Special Reference to Cross Elasticities.

As part of an EPSRC funded research project (GRK52522) entitled 'National Multi-Modal Travel Forecasts', a review of the demand forecasting literature has been conducted. The principal aim of this project is to develop a set of national and regional travel demand forecasts by land-based modes. Such models will contain a set of own and cross-elasticities which can be used in strategic demand forecasting. A review of the literature, alongside fresh empirical work, makes an important contribution to this. A review of aggregate models is contained in Clark (1996). Such models are based on collective behaviour such as market shares or travel volumes. In contrast, disaggregate models make the individual decision maker the unit of observation. Within this project, Wardman (1997a) has provided a review of disaggregate mode choice models developed in the inter-urban context in Great Britain whilst Whelan (1997) has provided a review of car ownership modelling and forecasting. This paper provides a review of comparatively recent research involving disaggregate mode choice models which have been developed in Great Britain in the urban context. The emphasis of this research is on cross elasticities for three reasons: Mode choice models are well suited to the estimation of cross-elasticities; The own elasticities provided by disaggregate mode choice models are underestimates since they do not account for behavioural responses other than mode switching (Oum et al., 1992); There has long been a view (Dodgson, 1991) that there is insufficient evidence regarding the degree of interaction between modes and this view remains (Acutt and Dodgson, 1995; Wardman et al., 1997) In contrast, aggregate models are well suited to the analysis of own elasticities since they take into account changes in the total number of trips yet they are generally limited in the extent to which they examine inter-modal competition and hence generally provide little evidence on cross-elasticities. In this paper, we have drawn upon studies made available to us as part of a review study conducted for the Department of Transport into the value of time (Wardman, 1997b). Much of this evidence was provided on the basis that the identity of the studies remains anonymous. We have therefore provided the key parameter estimates from 34 studies without revealing the identity of thes

Disaggregate Inter-Urban Mode Choice Models: A review of British Evidence with special Reference to Cross Elasticities.

The research reported in this paper forms part of EPSRC project GRK52522 entitled 'National Multi-Modal Travel Forecasts'. The principal aim of this project is to develop a set of national and regional travel demand forecasts by land-based modes. These demand models for car, bus and rail will be based on a hierarchy of techniques and hence there are several strands to this research. One aspect of the research involves the review of aggregate models, based on collective travel behaviour, and the evidence that they yield on own and cross elasticities. Whilst such models provide a wealth of information on own elasticities, and are particularly well suited to the analysis of the effects of exogenous factors on travel demand, they tend to make little allowance for competitive effects and hence provide little evidence regarding cross-elasticities. Furthermore, their nature is such that there can be only limited segmentation of the elasticities by relevant travel and socio-economic factors. Another aspect of the study is reviewing the evidence that is provided by disaggregate models where, in contrast to the aggregate models, the unit of observation is the individual decision maker. Since such models examine competition between modes, they are particularly useful in providing evidence on cross-elasticities. A further aspect of the work will be the actual estimation of relevant demand models and elasticities for a range of circumstances and by a variety of means. The final stage prior to application of the models is to draw all the evidence together in a consistent manner, drawing upon the strengths of different approaches and the various insights that they provide

Costs of Interchange: A Review of the Literature.

Interchange within mode influences the demand for that mode through the effect it has on time spent waiting, time spent transferring between vehicles and the inconvenience and risks involved, whilst interchange between modes has additional implications in terms of information provision, through ticketing and co-ordination. The valuation and behavioural impact of each of these factors will vary with an individual’s socio-economic and trip characteristics as well as with the precise features of the interchange. A reduction in the costs of interchange brought about by an improvement to any of the above factors will lead to increasingly ‘seamless journeys’ and such benefits which must be quantified. Indeed, this issue has been identified as an area of key importance in the Government’s Transport White Paper (DETR, 1998a) which states: Quick and easy interchange is essential to compete with the convenience of car use. This message was reiterated by the draft guidance for Local Transport Plans (DETR, 1998b), which called for: more through-ticketing, better connections and co-ordination of services, wider availability of information and improved waiting facilities. Rather than being perceived simply as a barrier to travel, quality interchange is now also being regarded as an opportunity to create new journey opportunities. A recent report on the subject of interchange (Colin Buchanan and Partners, 1998) claimed that : It will become more sensible and economic to base public transport networks around the concept of interchange rather than the alternative of trying to avoid it. whilst in response to the diffuse travel patterns made possible by increased car availability, CIT (1998) commented: people should readily be able to complete a myriad of journeys by changing services (and modes) if a through facility is not available. Ease of interchange should be something we take for granted. Regardless of the precise direction in which transport policy and public transport provision develop, practical constraints and the fact that the most heavily trafficked routes tend to have through services places limitations on the extent to which the need to interchange can be reduced whilst no matter how fully integrated different modes of transport are the need to transfer between them cannot be removed. In contrast, the need to change would inevitably increase with the adoption of a practice of building networks around interchange to create new journey opportunities. However, there is considerable scope to improve existing interchange situations or to design new ones which impose minimum costs. Although previous empirical research has focused on the need to interchange or not, and this remains important, it is essential that research is also directed at improvements which facilitate interchange.The aims of this study, as set out in the terms of reference, are centred around the demand side response to interchange rather than the technical supply side issues relating to improving interchange and integration which have been covered in other studies (Colin Buchanan and Partners, 1998; CIT, 1998). The objectives are: to explore the extent to which the reality and perception of interchange deters public transport use, absolutely and in relation to other deterrents to investigate how public transport users perceive interchange; how they make choices and trade-offs in travel cost and time and the influence of interchange attributes (e.g. information, through ticketing) on those choices to assess which components of interchange act as the greatest deterrent to travel to investigate the extent to which interchange penalties vary according to journey purpose, distance and time of travel (or other factors)

Econometric modelling of competition between train ticket types

INTRODUCTION The railways in Britain have a long history of using price discrimination backed up with product differentiation to significantly increase revenue over what might be obtained in an undifferentiated market. Whilst not as sophisticated as the yield management systems widely used in the airline industry, rail ticketing strategies are continually evolving, with new products emerging, unsuccessful products discontinued and gradual refinement of others. In recent years, there has been increased interest in modelling competition between different ticket types. The re-organisation of the railway industry in Great Britain has provided a greater commercial incentive to operators to price differentiate in order to maximise the revenue from their franchises. The policy of moderation of competition has allowed limited on-track competition, largely based around overlapping franchises but also with service extensions and new entrants, and this has stimulated product development and hence interest in ticket choice. Partly in response to the greater commercialisation of the railway industry, particularly where here is a degree of market power, the regulatory bodies have taken a greater interest in the range of tickets offered and their associated prices, travel restrictions and availability (SRA, 2003). This paper reports on research which was conducted as part of an update to the Passenger Demand Forecasting Handbook (PDFH), which contains a forecasting framework and recommended demand parameters that are widely used in the railway industry in Great Britain (ATOC, 2002), and as part of a project to provide the Strategic Rail Authority with evidence on cross elasticities between ticket types for use in its review of how it regulates rail fares

Demand Forecasting for New Local Rail Services: A Case Study of a New Service Between Leicester and Burton-On- Trent

Preston, J. and Wardman, M. (1988) "Demand Forecasting for New Local Rail Services: A Case Study of a New Service between Leicester and Burton-on-Trent". Workina Paver 260, Institute for Transport Studies, University of Leeds. This paper assesses the potential for a new rail service between Leicester and Burton-on-rent. In order to do this, three sets of demand forecasts were produced. These were based on Revealed Preference (RP) models that had been developed in West Yorkshire, a Stated Intentions (SI) survey of the Leicester-Burton corridor and Stated Preference (SP) models developed for the Ashby/ Coalville -and Outer Leicester areas. It was found that these three approaches gave a wide range of forecasts but it was felt that the SI survey, adjusted for the findings from the SP models, were likely to give the most reliable estimates of usage. As a result, it was concluded that, given patronage growth over time, total usage of the line would amount to between 3,000 and 4,000 trips on an average day. The demand forecasts were then used as input to an evaluation framework which took into account capital costs, operating costs, revenue and time savings. Even if actual usage reached the upper level of our forecasts it was shown that, although operating costs would be covered, only some of the capital costs would be paid back. Consideration of user time savings strengthens the case for the scheme but even so a return on capital would still not be achieved. Therefore, it was concluded that the case for a rail service between Leicester and Burton is, at best, marginal, although a number of ways to continue the feasibility study are suggested

Testing Contextual and Design Effects on Inter-Urban Motorists’ Responses to Time Savings

In the context of inter-urban motorists' route choices and the travel time savings offered by the UK's first toll motorway, a range of SP exercises tested various contextual and design effects. The design aspects relate to how the marginal benefit of time savings is influenced by the size and sign of the time saving, task complexity, presentation format, and whether the choice context is real. The contextual factors cover the impact of journey duration, attribute credibility, and where in the journey the time savings occur. The conclusions are largely credible but in some cases challenge established views and contribute significantly to understanding in this area

Review of fares elasticities in Great Britain

INTRODUCTION Empirical analysis of the behavioural impact of a wide range of travel variables has been conducted extensively in Britain over the past forty years or so. With the likely exception of the value of travel time (Wardman, 2001), the most widely estimated parameters have been price elasticities of demand and in particular public transport fare elasticities. The wealth of available evidence provides an excellent opportunity to obtain greater insights into fare elasticities and their determinants. There have been numerous notable reviews of price elasticities (Ely, 1976; TRF&, 1980; Goodwin and Williams, 1985; Goodwin, 1992; Oum et al, 1992; Halcrow Fox et al., 1993; Wardman, 1997; Nijkamp et al., 1998; Pratt, 2000; De Jong and Gunn, 2001; Graham and Glaister, 2002; VTPI, 2003). The unique features of this study are that it covers a much larger amount of public transport evidence and a broader range of issues than previous reviews and, more significantly, it has developed a model to explain variations in fare elasticities across studies. This review covers 902 public transport fare elasticities obtained from 104 studies conducted in Britain between 1951 and 2002. The markets covered are inter-urban rail travel, suburban rail travel, urban bus travel and London underground

Forecasting Motorists Long Term Behaviour in the Greater Nottingham Area

This report outlines work carried out to assess the factors that, in the medium and long term, may influence motorists' mode choice in the Greater Nottingham area. This work was based on four Stated Preference (SP) experiments that examined the choice between car and ordinary bus, car and bus-based park and ride, car and express bus and between departure times for car users. Just over 6,000 self completion questionnatres were distributed at random to residents in 28 wards. Over 1.700 usable responses were returned. representing a response rate of 29%. Despite a number of problems, a series of four strategic forecasting models were developed. These incoporated some important findings including that motorists value delay highly, value parking costs more highly than petrol costs and value adjusting their departure time less highly than in-vehicle time. The four forecasting models were then used to examine five scenarios; the introduction of park and ride, the effect of projected 2001 road traffic speeds, the effect of petrol cost increases, the effect of parking cost increases and the effect of decreasing bus in-vehicle time. Although there were a number of technical difficulties. our forecasts suggest that decreases in speeds, parking costs and petrol costs will not halt the growth in road traffic but will slow it down. Where possible motorists are more likely to change the time of theirjourney than theirmode. For dramatic changes in mode split both a big stick and big carrot are probably required. The big stick might be provided by some of parking control or road pricing, whilst the carrot might be some form of a high quality, fast bus network (or indeed other forms of public transport with a segregated right of way). The role of park and ride is likely to be relatively marginal but may be worth pursuing if part of an overall traffic management policy. There was little evidence from our models of there being any critical "thresholds" or "trigger points". However, many of the processes we have examined seem to have cumulative impacts and our forecasts identified the doubling of car journey times as being a possible "catalyst" which is likely to be achieved in the early part of the next centur