The demand for public transport. part II. supply and demand factors of public transport

Abstract

This two‐part article, concerned with the way public transport ridership is affected by the various relevant factors, is based on the Executive Summary of The Demand for Public Transport (Webster and Bly 1980), the report of the TRRL‐sponsored International Collaborative Study on Factors Affecting Public Transport Patronage. Part I of the article, which was concerned with the social and economic conditions in which public transport operates, showed the importance of the background factors such as income, car ownership and land use on public transport usage: it also indicated how the longer‐term impacts of the more direct demand factors (fares, service levels) often show themselves in changes in car ownership levels, activity patterns (i.e. where people live, work, shop, socialize, etc) and land‐use development.

Part II reviews the current state of knowledge on the effects of changes in fare levels and quality of service and of the introduction of various traffic and transport measures (traffic restraint, bus priority, etc): it outlines current methodology on costing public transport services and draws the supply and demand sides together in a consideration of particular strategies which are at the disposal of the operator, the planner and the policy maker.     

Effects of subsidies on urban public transport

Because of a general trend of increasing costs of public transport operations and higher subsidies (in some cases accompanied by falling patronage) the European Conference of Ministers of Transport (ECMT) initiated a study of subsidisation and sought the help of the Transport and Road Research Laboratory. The study, in which eighteen countries took part, was concerned with the aims of subsidy, the sources and conditions attached to subsidy, trends in subsidies and the effect of subsidies on patronage, fares, service levels, costs and productivity.The qualitative information concerning the aims of subsidy was analysed in relation to the likelihood of achieving such aims, taking into account current experience of attempts to switch car drivers to public transport. The quantitative information on trends referred to public transport stage services covering where possible the entire country and relating to the period 1965–77; these data were supplemented by data from 59 cities in different parts of the world collected in the course of a TRRL-sponsored study of travel demand factors. The relationship between patronage and service levels, and between subsidies and various operating factors, including costs and productivity, were studied using regression analysis and the general conclusion reached was that although the major part of the subsidy paid was reflected by reduced fares and improved service levels there may well have been some leakage into higher unit costs and manning levels.     

Redistributive effects of subsidies to urban public transport in Spain

This paper analyses the redistributive effects generated by the subsidization of urban public transport services. We estimate a two-stage model that takes into account both car ownership decisions and expenditure in urban public transport. In this way, we are able to measure the long run effects of income changes. Under the assumption that the user is the final beneficiary of the subsidies, and computing the share of the fare that is subsidized, we measure the progressiveness of the subsidies for different income groups and city sizes. Urban public transport subsidies are shown to be progressive. In larger urban areas this effect is considerably more important than in small ones.     

Meta-analysis of public transport demand

The present study uses meta-regression in order to explain the wide variation in elasticity estimates obtained in previous demand studies, and provide summaries of several bus demand elasticities.One important finding as to the price elasticity is that the often cited rule of thumb of −0.3 holds good if quality of service represented by vehicle-kilometres is treated as an exogenous variable, but not when it is treated as endogenous.Based on the results it is recommended that demand models should include car ownership, price of petrol, own price, income and some measure of service among the explanatory variables and that the service variable should be treated as endogenous.In previous meta-studies in this field focus has been on own price elasticity only while this study also includes elasticities with respect to, level of service, income, price of petrol and car ownership. The short run for the US are found to be −0.59, 1.05, −0.62, 0.4 and −1.48 respectively.     

The Gini index of demand imbalances in public transport

Transportation - The paper studies a general bidirectional public transport line along which demand varies by line section. The length of line sections also varies, and therefore their contribution...     

The effect of contract renewal and competitive tendering on public transport costs,subsidies and ridership

In this paper, we aim to estimate the effect of contract renewal as well as competitive tendering on public transport costs, subsidies, and ridership. More specifically, we examine to what extent (multiple) contract renewals and introduction of competitive tendering for long-term public transport contracts affect ridership, operational costs and subsidies in concession areas governed by public transportation authorities from 2001 until 2013 in the Netherlands. Our identification strategy improves on the literature as we are able to control for all time-invariant unobserved factors, such as network and area characteristics by using panel data. We show that when renewing long-term contracts, operational costs are reduced by at least 10%, whereas subsidies fall even stronger. For contracts that are renewed at least twice, the reduction in costs is even more substantial and in the order of 16%. We find that the effect of competitive tendering is completely absent, suggesting that the threat of competitive tendering is sufficient in a market where the majority of concessions is competitive tendered. Contract renewal not only reduces costs and subsidies, but simultaneously increases public transport ridership by 7.7%. Furthermore the vehicle-hours elasticity of operational costs is 0.40, pointing to strong economies of density. The geographical scale elasticity of operational costs is around one, which indicates constant returns to scale with respect to the geographical size of the concession area. This suggest that the current size of the Dutch concession area is optimal with respect to costs.     

The asymmetric effects of income and fuel price on air transport demand

Forecasts of passenger demand are an important parameter for aviation planners. Air transport demand models typically assume a perfectly reversible impact of the demand drivers. However, there are reasons to believe that the impacts of some of the demand drivers such as fuel price or income on air transport demand may not be perfectly reversible. Two types of imperfect reversibility, namely asymmetry and hysteresis, are possible. Asymmetry refers to the differences in the demand impacts of a rising price or income from that of a falling price or income. Hysteresis refers to the dependence of the impacts of changing price or income on previous history, especially on previous maximum price or income. We use US time series data and decompose each of fuel price and income into three component series to develop an econometric model for air transport demand that is capable of capturing the potential imperfectly reversible relationships and test for the presence or absence of reversibility. We find statistical evidence of asymmetry and hysteresis – for both, prices and income – in air transport demand. Implications for policy and practice are then discussed.     

A model to assess public transport demand stability

Transport authorities, especially those in developing countries where rising income stimulate increased car ownership rates, are often concerned with maintaining or increasing levels of public transport use. Therefore, the ability to identify clients at risk of abandoning the system can be valuable for remedial measures, allowing for more focused quality improvements. We present and apply a model that determines the probability of migrating from public to private transport at both aggregated and disaggregated levels. In application, the model predicted migration with 60% accuracy in the first preference recovery measure. The proposed model can improve the understanding of the behavior of public transport users, the analysis of demand stability and the factors influencing migration. This, in turn, can help to focus policy and management measures and increase the efficiency of public investment.     

The effects of planned and unplanned transfers on public transport users' perception of transfer routes

Many authorities are investing in new infrastructure to improve the quality of public transport (PT) services in the hope to increase mode switch from cars. The goal is to provide users with an integrated multimodal PT network by facilitating transfers. There exists a lack in the clarity of the attributes which defines a planned transfer and the effects of planned transfers on users' willingness to use routes with transfers. The present study provides approximate effects of ‘planned’ and ‘unplanned’ transfers on PT users' decisions to use transfer routes. The study focuses on two attributes of ‘planned’ transfers, integrated physical connection of transfers and information integration. A user preference survey was undertaken in Auckland, New Zealand. Analysis of the results shows that physical integration is more important than information integration for current PT users. Results also suggest that information integration has a greater influence on users of transfer services which are more closely aligned to being ‘unplanned’.     

Transfer demand prediction for timed transfer coordination in public transport operational control

Timed transfer coordination in public transit reduces passenger transfer time by providing seamless interconnected transfers. The problem arises when a Receiving Vehicle (RV) arrives to the transfer stop before a Feeding Vehicle (FV) carrying transferring passengers. Timed transfer coordination in operational control dynamically decides whether a RV is held at the transfer stop to allow transfers, or departs as scheduled. While transfer demand is essential for implementing timed transfer coordination, this variable is generally not available in public transit because of the lack of passenger transfer plans. The problem of acquiring this variable in real‐time has also received limited attention in the related literature. This paper proposes a new method to dynamically predict the transfer demand. We anticipate the transferring probability from each individual passenger by examining historical travel itineraries. Three different types of models (simple analytical, statistical, and computation intelligence model) are developed to forecast the number of transferring passengers. Numerical experiments using observed Automatic Vehicle Location and Automatic Fare Collection data from South East Queensland, Australia show the accuracy and applicability of the proposed models in timed transfer coordination. Copyright © 2017 John Wiley & Sons, Ltd.     

The influence of panel effects and inertia on travel cost elasticities for car use and public transport

Transportation - Studies on the impact of changes in travel costs on car and public transport use are typically based on cross-sectional travel survey data or time series analysis and do not...     

Travel satisfaction effects of changes in public transport usage

We study the effects of public transport use incentives on changes in travel satisfaction of participants that undergo behavior change. We use the results of an experiment conducted recently at the Massachusetts Institute of Technology and requiring a temporary use of public transport for commuting to work by habitual car drivers. We observe an increase in the average level of satisfaction with the commute to work of participants who switch to public transport after the temporary intervention. This increase is sustained to some extent several months after the intervention. Moreover, participants’ dissatisfaction is almost eliminated. We conclude that public transport use incentives are promising not only for encouraging sustainable travel behavior but also for increasing people’s satisfaction.     

Crowding in public transport systems: Effects on users,operation and implications for the estimation of demand

The effects of high passenger density at bus stops, at rail stations, inside buses and trains are diverse. This paper examines the multiple dimensions of passenger crowding related to public transport demand, supply and operations, including effects on operating speed, waiting time, travel time reliability, passengers’ wellbeing, valuation of waiting and in-vehicle time savings, route and bus choice, and optimal levels of frequency, vehicle size and fare. Secondly, crowding externalities are estimated for rail and bus services in Sydney, in order to show the impact of crowding on the estimated value of in-vehicle time savings and demand prediction. Using Multinomial Logit (MNL) and Error Components (EC) models, we show that alternative assumptions concerning the threshold load factor that triggers a crowding externality effect do have an influence on the value of travel time (VTTS) for low occupancy levels (all passengers sitting); however, for high occupancy levels, alternative crowding models estimate similar VTTS. Importantly, if demand for a public transport service is estimated without explicit consideration of crowding as a source of disutility for passengers, demand will be overestimated if the service is designed to have a number of standees beyond a threshold, as analytically shown using a MNL choice model. More research is needed to explore if these findings hold with more complex choice models and in other contexts.     

Technical and environmental effects of biodiesel use in local public transport

Biodiesel use in local public transport could be especially significant in improving air quality in cities. The purpose of the experiments described in this paper was to evaluate the various (10, 20 and 50%) blends of biodiesel with diesel in the context of the engine and pollution aspects. As regards the experimental use of these findings on municipal buses, these experiments were the first reference in Hungary. The ages (15–20 years) and types of buses (Ikarus-280, Ikarus-260) used in the experiments are still common vehicles in Hungarian public transport. During our measurements, there was a significant difference between the change in fuel consumption of articulated and solo buses in traffic when compared to test bench measurements. The proportion of the engine performance reduction is nearly the same as that for biodiesel share in the blends. Most pollutants were decreasing (both at idle and full rpm), but this reduction is not directly proportional to the increase of the blending percentage. However, as for CO₂, emission increase was observed in the case of idle rpm in comparison to normal diesel operation, even though this phenomenon was not due to biodiesel use, but the catalytic converter and the fact that biodiesel was used for the first time in the engine concerned.     

The main determinants of the demand for public transport: a comparative analysis of England and France using shrinkage estimators

This study analyses the impacts of changes in fares, service supply, income and other factors on the demand for public transport on the basis of panels of English counties and French urban areas. The analysis is based on dynamic econometric models, so that both short- and long-run elasticities are estimated. Conventional approaches (i.e. fixed- and random-effect models) rely on the hypothesis that elasticities are the same for all areas. Having shown that this hypothesis is not valid for these data sets, the heterogeneity amongst areas is accounted for using a random-coefficients approach, and Bayesian shrinkage estimators.Estimated elasticities for France and England are compared, by using a common set of variables, similar time period and a common methodology. The results show a considerable variation in elasticities among areas within each country. The major conclusion is that public transport demand is relatively sensitive to fare changes, so that policy measures aimed at fare reduction (subsidisation) can play a substantial role in encouraging the use of public transport, thus reducing the use of private cars.     

Indirect production function and the output effect of public transit subsidies

This paper uses an indirect production function to decompose the effects of subsidies on output into the lump-sum, cost and inefficiency effects. Using 2006 data for U.S. transit systems it estimates an indirect production function and uses the results to calculate these effects. It finds that the lump-sum effects exceed the other effects and that the average total effect of the subsidies is a 4.72% increase in output. The range of the output change shows that in many transit systems the output increases from the subsidies are quite large. The paper suggests that reductions in allocative inefficiencies from the subsidies would result in very large increases in output.     

Build-to-order supply chain network design under supply and demand uncertainties

Supply chain disruptions are unintended, unwanted situations resulting in a negative supply chain performance. We study the supply chain network design under supply and demand uncertainty with embedded supply chain disruption mitigation strategies, postponement with downward substitution, centralized stocking and supplier sourcing base. We designed an integrated supply-side, manufacturing and demand-side operations network in such that the total expected operating cost is minimized. We modeled it in a deterministic equivalent formulation. An L-shaped decomposition with an additional decomposition step in the master problem is proposed. The computational results showed that parallel sourcing has a cost advantage against single sourcing under supply disruptions. In addition, the build-to-order (BTO) manufacturing mitigation process has its greatest impact with high variations on demands and is integrated with the component downward substitution. Lastly, the manufacturer needs to order differentiated components to cover its requirement for maximal product demand to prevent the loss of sale, even with fewer modules in stock.     

Assessing the financial and social costs of public transport in differing operating environments and with endogenous demand

This paper uses a previously developed spreadsheet cost model which simulates public transport modes operated on a 12-km route to analyse the total costs of different passenger demand levels. The previous cost model was a very powerful tool to estimate the social and operator costs for different public transport technologies. However, as the model is strategic, some basic assumptions were made which are relaxed in this paper. First, the speed-flow equation in the original spreadsheet model assumes that speed decreases according to the ratio of the current frequency and the lane capacity which is based on the safety headway without taking into account passenger boardings. However, this may vary in different operating environments. Therefore, the speed-flow equation is improved by moving from a linear equation to a piecewise equation that considers the features of different operating environments. Second, the model assumes that supply is sufficient to meet demand. However, when the level of demand is high for the lower-capacity public transport technologies, passengers may find the incoming vehicle full and therefore, they have to wait more than one service interval. This paper applies queuing theory to investigate the probability of having to wait longer than the expected service headways which will affect the average passenger waiting time. The extra waiting time for each passenger is calculated and applied in the spreadsheet cost model. Third, the original model assumed that demand was externally fixed (exogenous). To evaluate the differences after applying these equations, endogenous demand rather than exogenous demand will be investigated by using the elasticities for passenger waiting time and journey time.     

Dynamic at-stop real-time information displays for public transport: effects on customers

Dynamic at-stop real-time information displays are becoming more and more ubiquitous in modern public transport. Reactions and attitudes towards these systems are very positive. But there is a need to provide a comprehensive framework of the possible effects that these kinds of displays can have on customers.The seven main effects described in this paper are: (A) reduced wait time, (B) positive psychological factors, such as reduced uncertainty, increased ease-of-use and a greater feeling of security, (C) increased willingness-to-pay, (D) adjusted travel behaviour such as better use of wait time or more efficient travelling, (E) mode choice effects, (F) higher customer satisfaction and finally (G) better image.Two studies are presented in this paper. Study I supports and proves that perceived wait times can be reduced by 20% by employing a before–after implementation evaluation study with questionnaires on a tramline. Study II shows the effects of real-time displays on behaviour in the form of adjusted walking speeds, by using a behaviour observation method in a subway station.The effect framework does not claim completeness and many effects are related to each other. However, the framework is a useful basis for designing evaluation studies and provides arguments in favour of at-stop real-time information displays.     

The organization of public transport in Denmark

The sharp contrast between the public transportation needs of Greater Copenhagen and provincial Denmark has led to significant differences in policy and organizational structure for public transport in the two regions. Outside Copenhagen the period 1965–1975 saw a rapid decline in rural public transport supply and a rise in special services (school buses, etc.). A 1978 law requiring county councils to prepare comprehensive regional transport plans reversed this trend. Most counties now have economically responsible transport corporations which contract with public and private operators for service. School routes have been opened, train and bus schedules have been coordinated and zonal fare systems have been introduced. In Greater Copenhagen urban sprawl has promoted a gradual public take-over of most transport services in the region, culminating in an almost all-pervasive “public works” type of transport corporation under regional authority in the late 1970s.