Lessons from travel planning and road user charging for policy-making: through imperfection to implementation

In 1978 Gunn published a seminal paper which explained why implementation of policy is so difficult. The paper set out 10 conditions, which should be satisfied if perfect implementation is to be achieved. Whilst it is clear that perfect implementation is not possible in the real world, and Gunn has subsequently been criticised for his ‘top-down’ approach to decision-making, these conditions do, nonetheless act as an effective framework through which to evaluate good practice in the implementation of urban transport policy instruments. Two urban transport policy instruments, which form an increasingly important element of the Government's strategy in the UK for reducing the demand for private transport as set out in a New Deal for Transport (DETR, 1998), are travel plans and road user charging. Travel plans are a relatively recent policy instrument in the UK and seek to reduce trips to work by car by providing, through individual employers, a targeted, integrated package of incentives and disincentives to influence commuters' choice of mode of travel to and from the workplace. Road user charging, whereby motorists are charged for the road space they use in urban areas, seeks to reduce the congestion problem via the price mechanism, and has a longer history in the UK. To date the implementation of travel plans in the UK has been more widespread than that of road user charging. It is fair to say, however, that the widespread implementation of both urban transport policy instruments is a complex and sensitive area for decision-makers.The aim of this paper is firstly, to analyse travel plans and road user charging in the UK with respect to the conditions for perfect implementation put forward by Gunn and secondly, to highlight the elements of good practice, pertinent to the implementation of road user charging, in the process of the implementation of travel plans. Overall, the paper uses Gunn's theoretical framework as a basis for recommendations for better decision-making that will aid the wider implementation of both travel plans and road user charging internationally.     

Detecting urban road network accessibility problems using taxi GPS data

Urban population growth and economic development have led to the creation of new communities, jobs and services at places where the existing road network might not cover or efficiently handle traffic. This generates isolated pockets of areas which are difficult to reach through the transport system. To address this accessibility problem, we have developed a novel approach to systematically examine the current urban land use and road network conditions as well as to identify poorly connected regions, using GPS data collected from taxis. This method is composed of four major steps. First, city-wide passenger travel demand patterns and travel times are modeled based on GPS trajectories. Upon this model, high density residential regions are then identified, and measures to assess accessibility of each of these places are developed. Next, the regions with the lowest level of accessibility among all the residential areas are detected, and finally the detected regions are further examined and specific transport situations are analyzed.By applying the proposed method to the Chinese city of Harbin, we have identified 20 regions that have the lowest level of accessibility by car among all the identified residential areas. A serious reachability problem to petrol stations has also been discovered, in which drivers from 92.6% of the residential areas have to travel longer than 30 min to refill their cars. Furthermore, the comparison against a baseline model reveals the capacity of the derived measures in accounting for the actual travel routes under divergent traffic conditions. The experimental results demonstrate the potential and effectiveness of the proposed method in detecting car-based accessibility problems, contributing towards the development of urban road networks into a system that has better reachability and more reduced inequity.     

Identification of determinants for rescheduling travel mode choice and transportation policies to reduce car use in urban areas

This paper presents a qualitative analysis about the determinants related to rescheduling travel mode decisions during the activity scheduling process. Notably, we were interested to study changes between intention and behavior. Data used came from an in-depth Computer Assisted Telephone Interview (CATI) follow up survey to habitual drivers carried out during the implementation of a panel survey. An interpretative qualitative method based on Analytic Induction was used to cope with the complex nature of rescheduling decisions and the characteristics of the data. The Theory of Planned Behavior has been used to gain a better understanding of the reasons associated with rescheduling travel mode decisions and to obtain a possible explanation of the phenomena studied. In our sample, 12 codes were identified as the main determinants of travel mode changing. Main reasons for rescheduling a travel mode are different considering gender, age, and the type of travel mode change. Main reasons for changing a nonprivate preplanned travel mode to a private travel mode are different considering the type of travel mode preplanned. New determinants of rescheduling decisions different from those associated with other activity scheduling decisions previously identified emerge when analyzing travel mode changes. A number of important sustainable transportation policies to reduce car use in urban areas are derived from the results of this study.     

Gravity models for dynamic transport planning: Development and implementation in urban networks

This paper describes the development and comparison through a real-life implementation of dynamic extensions of the entropy-based gravity model of trip distribution for dynamic transport planning purposes in urban networks. The single dynamic gravity model (SDGM) accounts only for the inter-period (long-term) evolution of travel demand. The doubly dynamic gravity model (DDGM) takes into account both the inter-period and intra-period (short-term or within-day) evolution of travel demand. The computational analysis and explanation of the differences between the two models are demonstrated in relation to different demand inputs, model parameters and performance measures.     

Exploring the effectiveness of bus rapid transit a prototype agent-based model of commuting behavior

The introduction of Bus Rapid Transit (BRT), typically involving the use of exclusive bus lanes and related bus priority measures, is increasingly advocated as a flexible and cost-effective way of improving the attractiveness of public transit in congested urban areas by reducing travel times and variability. These schemes typically involve the reallocation of road space for exclusive use by buses, presenting commuters with potentially competing incentives: buses on BRT routes can run faster and more efficiently than buses running in general traffic, potentially attracting commuters to public transit and reducing congestion through modal shift from cars. However, a secondary impact may also exist; remaining car users may be presented with less congested road space, improving their journey times and simultaneously acting as an incentive for some bus-users to revert to the car. To investigate the potential for these primary and secondary impacts, we develop a prototype agent-based model to investigate the nature of these interactions and how they play out into system-wide patterns of modal share and travel times. The model allows us to test the effects of multiple assumptions about the behaviors of individual agents as they respond to different incentives introduced by BRT policy changes, such as the implementation of exclusive bus lanes, increased bus frequency, pre-boarding ticket machines and express stops, separately and together. We find that, under our assumptions, these policies can result in significant improvements in terms of individual journey times, modal shift, and length of rush hour. We see that the addition of an exclusive bus lane results in significant improvements for both car users and bus riders. Informed with appropriate empirical data relating to the behavior of individual agents, the geography and the specific policy interventions, the model has the potential to aid policymakers in examining the effectiveness of different BRT schemes, applied to broader environments.     

Measuring the structural determinants of urban travel demand

To be best prepared for tomorrow's cities we need to forecast urban travel demand. To this end, this study calibrates an urban travel demand model, which uses the principal structural variables that have been identified in the literature. It uses a robust econometric method, which has been little applied in the sphere of transportation. The results show that two variables stand out from the others: the user cost of transport – by private car and public transport – and urban density. It is surprising, but explicable with the available data, that the demand functions estimated for a given country are independent from the group of countries to which it belongs.     

Dependence between travel distance,individual socioeconomic and health-related characteristics,and the choice of the travel mode: a cross-sectional study for Kaunas,Lithuania

The aim of this study was to analyse the associations between individual socioeconomic and health-related characteristics, travel distance, and the choice of different travel modes in urban population. A cross-sectional study included 932 adults of Kaunas city, Lithuania. The choice of the travel mode and individual characteristics were self-reported by the participants, and their travel routes were calculated using the geographic information system. Multivariate logistic regression was used to assess the most significant factors determining the choice of a car, cycling, walking, or public transport. In total, 529 participants reported using a car, of whom 65.8% had medium or high education levels. These participants were more likely to be younger, male, married, and employed. Among bicycle users, statistically significant differences between the employment status, body mass index, and travel distance were observed. Walkers were significantly more likely to be older, those with lower incomes, unemployed, and travelling the shortest distances. The analysis of the travel distance on the choice of the travel mode revealed that men travelled longer distances with a car compared to women. The employment status was significantly associated with travel distance by car or public transport. Employed individuals travelled longer distances by public transport or by car, compared to unemployed individuals. Among bicycle users, we found that people with higher levels of education and overweight individuals cycled the longest distances. Our study emphasizes the importance of considering different individual characteristics when analysing the choice of transport modes. It provides evidence that is relevant for all urban populations on the choice of the transport mode, particularly considering active versus passive transport.     

Overcoming barriers to the implementation of car parking charges at UK workplaces

Charging employees to park at their places of work is a transport policy measure advocated by the UK government as a means of reducing car commuting and hence achieving the twin objectives of reducing congestion and combating environmental degradation, especially in urban areas. The empirical effects of employee parking charges have been analysed (see for example [Willson, R.W., Shoup, D.C., 1990. Parking subsidies and travel choices: assessing the evidence. Transportation 17, 141–157; Department for Transport (DfT), 2002. Making travel plans work: report on case studies. London: DfT (Also available at www.local-transport.dft.gov.uk/travelplans/guides/index.htm)]). There is, however, a dearth of literature examining the practicalities of employee car parking charge implementation in those few organisations that haves done so. Based on empirical studies of 11 UK workplaces, this paper examines the reasons for and the practicalities of implementation and concludes by considering the barriers to the wider adoption of this policy.     

The sustainable mobility paradigm

This paper has two main parts. The first questions two of the underlying principles of conventional transport planning on travel as a derived demand and on travel cost minimisation. It suggests that the existing paradigm ought to be more flexible, particularly if the sustainable mobility agenda is to become a reality. The second part argues that policy measures are available to improve urban sustainability in transport terms but that the main challenges relate to the necessary conditions for change. These conditions are dependent upon high-quality implementation of innovative schemes, and the need to gain public confidence and acceptability to support these measures through active involvement and action. Seven key elements of sustainable mobility are outlined, so that public acceptability can be more effectively promoted.     

Effects of parking and cordon charge policies on tourist's modal shift in central business district of Mashhad city,Iran

The second largest holy city of the world, Mashhad, attracts high volumes of tourists and pilgrims every year. Most visitors travel by private car and are a source of considerable funds for the local economy. Among road users, tourists as one of the major traveller categories in Mashhad city behave differently due to the particular trip purpose. The aim of this research is to model tourist's shifting modes of travel behaviour when policy measures, such as the parking and cordon fares, are implemented. The tourists’ preferences were examined using binary logit analysis when different options of travel cost and time scenarios were provided. Results indicate that travel time, parking cost, cordon cost, education level and vehicle price influence tourist's modal choice. In addition, the finding shows that congestion pricing will be more effective than a parking pricing strategy in encouraging switching of modes.     

Assessment of the socio-spatial effects of urban transport investment using Google Maps API

We analyze the spatially distributed impacts of transport investment in urban highways and public transport with a novel methodology based on the capabilities of online technology to replicate the (unobserved) condition without highways. This is based upon the intensive use of Google Maps API (GMA) to obtain travel times between each origin-destination pair at a highly detailed level to reveal the effects of new infrastructure on different zones and groups within a city. Santiago is used as a case study, as the city introduced 150 km of urban highways, a reorganization of surface transit, and new subway lines in a relatively short period. We show that the high-income segment of the population has been the most favored, simultaneously increasing the difference between transit and car travel times in those areas where car ownership is low, stimulating the acquisition of a car.     

Interrelations between travel mode choice and trip distance: trends in Germany 1976–2002

In recent decades, trends in travel behaviour have been characterised by increasing trip distances and a modal shift towards the private car. This paper reports findings from longitudinal analyses of the German nation-wide travel survey KONTIV for the period 1976–2002. It focuses on travel mode choice, subdivided by distance categories, and also takes car availability and city size into account. In addition, trends in car availability itself are examined by city size categories. The results indicate that even within the same distance categories car use has considerably increased. In some cases bicycle use has increased as well. Gains in the use of the private car are mainly at the expense of trips on foot and by public transport. Accordingly, the shift in modal split towards the car is not (only) caused by increasing trip distances but took place even within distance classes. Once car availability is taken into account, the modal shifts appear to be considerably weaker. This suggests that once car availability is held constant the decision rationales of mode choice for a certain trip distance have remained relatively stable. The increase in motorisation over the study period was considerably weaker in large cities than in small towns, although the cities started from a lower level in the 1970s. Thus, the motorisation divide between cities on the one hand, and suburban and rural areas on the other hand has become ever wider. For travel mode choice, the picture is similar. What is more, the results suggest that even car owners are more inclined to walk a given distance in the cities than in small towns, even more so if they live in a central urban area. The built environment, thus, appears to have a strong impact on whether an available car is used or not.     

Determinants of car ownership in rural and urban areas: a pseudo-panel analysis

This paper examines the factors determining car ownership for households living in rural and urban areas. A dynamic car ownership model is estimated using a pseudo-panel approach, based on data from Family Expenditure Surveys in the UK for 1982–1995. The results show that rural households' car ownership is far less sensitive to motoring costs than that of their urban counterparts. The implication of these results is that general increases in the costs of car transport would pose a considerable economic burden for rural households, and that other area-specific transport measures may be more suitable, particularly from an equity point of view.     

Socioeconomic differences in public acceptability and car use adaptation towards urban road pricing

Urban road pricing is regarded as an effective instrument to reduce traffic congestion and environmental-related problems in metropolitan areas. Whereas the overall impact of urban road pricing on car use adaptation and public acceptability is known, there are only inconsistent results concerning the socioeconomic differences in the response towards road pricing. However, this knowledge is necessary for the development of urban road pricing packages. This paper uses a segmentation approach to identify groups of car users with a similar background in relevant socioeconomic variables and compares their responses towards road pricing. Three groups are identified: young families, suburban families, and singles and couples. These groups indeed differ in their car use adaptation towards urban road pricing as well as in their preferred revenues use. While all three groups significantly reduced their private car use, the young families reduced their car use most, followed by the group of singles and couples. Complementary measures are discussed that are believed to facilitate car use adaptation of each group in response towards urban road pricing.     

Key research themes on ICT and sustainable urban mobility

Abstract

Information and communication technologies (ICTs) are hypothesized to replace or change the use of the transport system by facilitating new or different activities. This article offers a review of more than 40 years of research regarding the relationship between ICTs and urban mobility. We discuss the expectations for the changes in travel demand, travel patterns, and the urban form as a result of the development and introduction of ICTs. Much of the interest in the relationships between ICTs and mobility is premised on the expectation of substitution effects, but empirical findings often suggest more complex effects than direct substitution. Although research on single types of travel activity may sometimes indicate simple substitution effects, examination of the broader impacts may also reveal travel generation effects as well. As such, ICTs do not simply substitute mobility patterns but change them. A growing body of research focuses on changing mobility patterns (in terms of time and space), changes in the experience of travel and changes in the perceptions of travel costs due to the interaction between old and new technologies for overcoming distance. ICTs are gradually becoming embedded within the transport system, enabling flexibility, multitasking, and an increase in human activities.     

Indicators of transport and accessibility problems in rural Australia

Australia belongs to a small group of countries that are low density but affluent, and characterised by very high vehicle ownership levels but very little public transport in rural areas. It is widely believed that there are few problems of mobility and accessibility, apart from long distances, because everyone has a car. A literature review generally confirms this perception, although there are hardly any suitable local case studies. An analysis of the rural areas of New South Wales, Victoria and South Australia sought indicators of transport-related problems, using mainly census data. While the basic urban/rural distinction is clearly defined, within the rural areas patterns of vehicle ownership are unusual, and in the remotest areas are not as high as would be expected. Relationships with socio-economic variables are not consistent. Accessibility measures are incorporated in the analysis, and a travel needs index suggested. Appropriate case studies are required to establish travel behaviour patterns and the responses of disadvantaged groups.     

Bi-level optimization approach for configuring population and employment distributions with minimized vehicle travel demand

Compact development aims to lead to dense and mixed distributions of population and employment in land use planning which may result in reduced vehicle miles traveled (VMT). However, determining an optimum or desirable configuration of population and employment distribution to achieve the compact development goal remains challenging due to numerous competitive development alternatives or possible exacerbated traffic congestion as a result of over-intensification of urban land use. To address this challenge, a systematic approach is proposed with a bi-level optimization model aiming to find out an efficient population and employment map for vehicle travel reduction. The upper level of the model is formulated to minimize VMT and vehicle hours traveled (VHT) varying with possible changes in population and employment densities. The lower level is based on a tour-based travel demand model to mechanistically represent the response of travel choices to those changes. The programming is solved by a Genetic Algorithm. The proposed method is demonstrated through a case study of Hamilton County, Ohio, U.S. The results indicate that a more compact urban form reduces VMT; however, it may cause longer VHT depending upon the density. To avoid urban overconcentration and reduce both VMT and VHT simultaneously, a compact urban development configuration with a population density < 5289 persons/mi² and the employment density < 3282 jobs/mi² is recommended for the area. As a negative relationship demonstrated between transit headway reduction and vehicle travel demand, strategies for improving transit provision are helpful to reducing vehicle travels in compact development scenarios.     

Car-sharing organizations: The size of the market segment and revealed change in mobility behavior

Car-sharing organizations (CSO) have recently spread throughout central European cities and currently have 20000 members. They lower individual fixed costs of car availability change the incentive structure of private vehicle use by transforming nearly all costs into variable costs. A survey of all current Austrian CSO members is used to identify the characteristics significant of members. A procedure is proposed to quantify urban local market segment potentials and is applied to two residential areas. The net impact of CSOs depends on how the new incentive structure changes mobility behavior. A controlled experiment of voluntary new members was carried out to compare pre-membership and membership trip structure and modal split. Results indicate a substantial reduction of aggregate private vehicle mileage. While the share of trips by car is constant, changes in trip length are observed, with there being different changes for households which previously owned a car and those which did not. Combining behavior impact with market segment size results in the quantification of emission reduction and car ownership reduction (land use demand) due to car-sharing, which is a decentralized demand-side transport policy.     

Affective-symbolic and instrumental-independence psychological motives mediating effects of socio-demographic variables on daily car use

An empirical study investigates the extent to which affective-symbolic and instrumental-independence psychological motives mediate effects of socio-demographic variables on daily car use in Sweden. Questionnaire data from a mail survey to 1134 car users collected in 2007 were used to assess the relationships daily car use as driver or passenger have to sex, household type (single or cohabiting with or without children), and residential area (urban, semi-rural or rural). Reliable measures of affective-symbolic and instrumental-independence motives were constructed. The results show that households with children use the car more than households with no children, that men make more car trips as drivers than women who use the car as passenger more than men, and that households living in rural areas use the car more than households living in semi-rural areas who use the car more than households living in urban areas. An affective-symbolic motive partially mediates the relationship between the number of weekly car trips and sex, the instrumental-independence motive partially mediates the relationships between weekly car use and percent car use as driver and several of the socio-demographic variables (living in urban vs. rural residential area for both measures; sex and living in urban vs. semi-rural residential area for percent car use as driver). Of several other socio-demographic variables (age, employment, and income) affecting car use, only the relationship of the number of cars to percent car use as driver was (partially) mediated by the instrumental-independence motive.