Determining intra-urban spatial accessibility disparities in multimodal public transport networks

Urban rail systems have been added to public transport systems, thereby changing distribution disparities in urban spatial accessibility. These disparities reflect both the ability of the public transport system to meet the needs of residents and the locational pros and cons of public service facilities. In this paper, integrated accessibility metrics are used to assess the disparities in Nanjing, Jiangsu Province, China. This is achieved by dividing the urban space into a multilevel grid that can be easily combined with grid-based population data to facilitate accessibility modeling, calculation, and evaluation. Additionally, an acquisition method for more accurate travel time data in the multimodal public transportation network was developed on the basis of an Internet mapping service. This provides a realistic, multimodal, door-to-door modeling approach that avoids the requirement of building complex traffic networks through Geographic Information System (GIS) software and simplifies road network modeling efforts. The results show that this modeling method can be used to reflect the accessibility disparities in the Nanjing urban space objectively and accurately.     

Quantifying spatial gaps in public transport supply based on social needs

This paper concerns a research project to identify spatial gaps in public transport provision for people who are socially disadvantaged. The paper outlines the research context for measurement of public transport supply and needs, and then describes the methodology developed for an application in Melbourne, Australia. Results of the application are described including key findings on spatial gaps in services relative to social needs. The research identifies significant gaps between services supplied and social needs for transport services. Consistency of these findings with research in other Australian cities are noted. Implications for policy development are suggested.     

A multi-criteria approach of assessing public transport accessibility at a strategic level

This paper presents an approach for accessibility categorization in areas where there is no extensive data available to run the conventional analysis. The presented method has the advantages of the lower data requirements and the utility of the results. Three benchmarks were selected to evaluate transit accessibility. The first one (transit coverage) investigates the spread of the service, and it is used to assess the percentage of people in a district that can access the service within a comfortable access distance. The second (transit supply) is an effectiveness measure of the magnitude of available infrastructures such as stops, or stations over the population or land area of the underlying region. The third (route diversity) represents the variety of routes to and from different areas via transit services. Various indicators were used to assess these benchmarks. Within the context of multi-criteria decision-making, TOPSIS (Technique of Order Preference by Similarity to Ideal Solution) allows the direct comparison of measures of different units, and it is used to evaluate the relative scores of the various districts' benchmark. A K-clustering method was used to numerically categorize the areas into five groups, reflecting on the criteria levels. A case study of Abu Dhabi city is used to demonstrate the details of the procedures. The detailed analyses were used to depict districts and corridors with particular deficiencies and as such suggesting remedy strategies. The method can help transit authorities identifying the most suitable types of facilities, infrastructure, or routes that a district may need to improve its accessibility.     

Understanding accessibility through public transport users' experiences: A mixed methods approach

The quantitative measurement of accessibility through public transport has become more complex and accurate over time. However, it lacks many of the deeper nuances of how people actually experience their travel environments. Our previous works have highlighted the importance of incorporating the lived travel experiences of passengers within accessibility indicators, considering the quality of the walking environment and different attributes of the public transport services.Building on these works, this mixed-method research seeks to further improve the characterization of accessibility according to users' travel experiences, as described by those attributes that inhibit or enhance access to opportunities within the city. We use content analysis of focus groups, data gathered in a brief survey and sociodemographic and public transport data for our analyses. Our main contributions are (i) to develop a conceptual framework to analyze qualitative data on how people relate and discuss their public transport accessibility experiences and (ii) to develop accessibility indicators differentiating user perceptions. We apply this novel conceptual framework and methods to the unique urban morphology of two municipalities of Santiago de Chile.We identified different ‘socially constructed’ narratives for buses and metro. The participants focused on barriers to accessibility, showing an important relationship between them, as well as substantial differences in their overarching positive perception of metro and negative for buses. However, when disaggregating the analysis by primary transport mode and location, we found ‘hidden’ values for buses, recognizing its capillarity and underlying connectivity with the metro system. Furthermore, we found a dissimilar perception of transport environments when disaggregating the analysis by gender, age and location, which translated into different accessibility profiles for the various public transport users. From these experiential qualitative perspectives, it was thus possible to determine some attributes that had been previously overlooked in more quantitative studies but which are important when analyzing public transport accessibility for different population groups.     

Identifying attributes of public transport services for urban tourists: A data-mining method

The current work focuses on Quality of Service (QoS) of Public Transport (PT) attributes in urban tourist destinations. In particular, we aim to reveal which attributes are most significant for tourists prior to their arrival at their destination, as reflected in questions posted in TripAdvisor Question and Answer forums, a widely used social media platform.We used a data-mining method to classify questions into categories relevant to QoS, using a sample of 8905 items posted between 2005 and 2018 in TripAdvisor forums for seven urban destinations in the United States and Western Europe. We found four PT-QoS attributes: Pricing and ticketing, Accessibility, Trip duration, and Service availability (hours of operation and frequency). These attributes have similar relative significance for all destinations, origins, seasons, and years we checked. Hence, they can help service operators and policymakers to understand tourists' preferences and to adjust PT services accordingly.     

Estimating the influence of crowding and travel time variability on accessibility to jobs in a large public transport network using smart card big data

Accessibility metrics are gaining momentum in public transportation planning and policy-making. However, critical user experience issues such as crowding discomfort and travel time unreliability are still not considered in those accessibility indicators. This paper aims to apply a methodology to build spatiotemporal crowding data and estimate travel time variability in a congested public transport network to improve accessibility calculations. It relies on using multiple big data sources available in most transit systems such as smart card and automatic vehicle location (AVL) data. São Paulo, Brazil, is used as a case study to show the impact of crowding and travel time variability on accessibility to jobs. Our results evidence a population-weighted average reduction of 56.8% in accessibility to jobs in a regular workday morning peak due to crowding discomfort, as well as reductions of 6.2% due to travel time unreliability and 59.2% when both are combined. The findings of this study can be of invaluable help to public transport planners and policymakers, as they show the importance of including both aspects in accessibility indicators for better decision making. Despite some limitations due to data quality and consistency throughout the study period, the proposed approach offers a new way to leverage big data in public transport to enhance policy decisions.     

Job accessibility through public transport and unemployment in Latin America: The case of Montevideo (Uruguay)

Accessibility to job opportunities is one of the factors that explains labor outcomes. For developing countries, public transport plays a key role in providing the population with access to employment opportunities. This paper aims to quantify accessibility by public transport to employment in Montevideo, Uruguay and to explore how accessibility to job opportunities via public transport relates to unemployment. To do so, we calculate a cumulative measure of accessibility to job opportunities for 1063 small zones—approximately 4–6 blocks each—within Montevideo. This measure yields accurate data on accessibility and can be assigned to individual households. Accessibility in Montevideo is unevenly distributed among social strata and is concentrated within the central (and wealthier) areas of the city. In addition, a multilevel logistic regression analysis indicates that greater accessibility to jobs via public transport is associated with a lower probability of being unemployed. This finding suggests that improving accessibility to job opportunities via public transit may enhance individual labor outcomes.     

Spatiotemporal accessibility to supermarkets using public transit: an interaction potential approach in Cincinnati,Ohio

Improving nutrition in urban regions involves understanding which neighborhoods and populations lack access to stores that sell healthy foods, such as fruits and vegetables. To this end, recent work has focused on mapping regions without access to places like supermarkets, often terming them ‘food deserts’. Until recently, this work has not considered residents’ mobility as facilitated by transportation systems, and even among those that do, few have considered alternative forms of transportation, like public transit, opting for automobile-oriented travel assumptions. This paper analyzes people’s spatio-temporal constraints to accessing supermarkets, and focuses on the transit commuting population. Analysis of commute data from Cincinnati, Ohio shows there are a significant number of residents that have improved access to supermarkets when a grocery shopping trip is made on the way home from work, than if they were to depart from their home location. These results extend previous work showing relatively few automobile commuting residents have better access to supermarkets given their work locations.     

Extending public transit accessibility models to recognise transfer location

A longstanding issue for public transit agencies has been how to assess the performance of transit service including spatial service coverage to meet the transport needs of the community. The conventional approach quantifies accessibility using door-to-door travel time in such a way that accessibility declines as the travel time to the opportunity increases. A new approach to modelling transit accessibility is proposed by incorporating the potential effect of transfer location. It builds on the premise that transit users may have a preference for a transfer location best located relative to the trip origin and destination points. The model is tested in Brisbane's bus network which has a radial form, where inner-city suburbs have relatively higher accessibility than outer-city suburbs, if only travel time is counted. Incorporating the transfer location refines the accessibility modelling so that some outer-city suburbs located along the major bus corridors have a relatively higher accessibility level. The new model also suggests that inner-city suburbs do not necessarily have better accessibility. Suburbs close to the city centre may have shorter transit travel time to reach other suburbs, but they do not have a well-connected transit network to other suburbs through service transfers.     

Transit Deserts: Equity analysis of public transit accessibility

Areas, where disadvantaged and transit-dependent populations are provided with inadequate amounts of transit supply, can be labeled transit deserts. Exploring transit deserts may help transit agencies improve accessibility to services while improving transit distribution and equity. This study utilizes the concepts of transit demand and transit supply to identify transit deserts in the City of Dallas. The comprehensive public transit accessibility (CPTA) score is introduced to evaluate accessibility to transit and to provide a holistic view of transit supply. While previous studies have primarily used proximity or spatial indicators to describe accessibility, this study utilizes a comprehensive set of spatial and temporal measures (connectivity to the network, connectivity to destinations, service frequency, flexibility, and time efficiency) to estimate accessibility to transit. Overlapping areas of high demand (transit dependency) and low supply (as measured using the CPTA) are then characterized as transit deserts. The CPTA score and its application to the analysis of transit deserts provides a universal framework which can be broadly applied by transit agencies, city officials, and transit stakeholders. The contributions of this study are as follows: first, developing a comprehensive framework to estimate transit supply or accessibility; and second, introducing a methodology for identifying transit deserts.     

Purpose-driven public transport: creating a clear conversation about public transport goals

Public transport faces an increasingly intense conflict between patronage goals and coverage goals. Broadly speaking, patronage goals seek to maximize patronage of all types, while coverage goals lead to the provision of service despite low patronage – to achieve social inclusion objectives for example. The conflict between these goals follows inevitably from the underlying structure of the public transport product, including both its costs and geometry.The tradeoff between patronage and coverage is the type of value-judgment that elected officials are paid to make. The paper presents a means of quantifying the tradeoff, to facilitate public discussion and decisions on how to balance these priorities. These strategies are designed to ensure that the decision about how to balance social versus patronage goals is made consciously rather than inadvertently, with a clear understanding of the consequences of the choice.     

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.     

Inter-regional air transport accessibility and macro-economic performance in Japan

Although there have been various studies on macro-economic effect of public investment, not much attention has been paid to the impact of actual accessibility realized by transport industry and infrastructure. In this paper, we performed a cross-sectional analysis of 47 prefectures in Japan between 1995 and 2000 by Cobb–Douglas production function and growth regression approach. The results explain why deregulation and infrastructure development in air transport during 1990s manifest mixed results of inter-regional accessibility and per-capita GDP growth for core and peripheral areas in Japan.     

Making public transport financially sustainable

Over the past two decades, Germany has improved the quality of its public transport services and attracted more passengers while increasing productivity, reducing costs, and cutting subsidies. Public transport systems reduced their costs through organizational restructuring and outsourcing to newly founded subsidiaries; cutting employee benefits and freezing salaries; increasing work hours, using part-time employees, expanding job tasks, and encouraging retirement of older employees; cooperation with other agencies to share employees, vehicles, and facilities; cutting underutilized routes and services; and buying new vehicles with lower maintenance costs and greater passenger capacity per driver. Revenues were increased through fare hikes for single tickets while maintaining deep discounts for monthly, semester, and annual tickets; and raising passenger volumes by improved quality of service, and full regional coordination of timetables, fares, and services. Those efforts by public transport agencies were enhanced by the increasing costs and restrictions on car use in German cities. Although the financial performance of German public transport has greatly improved, there are concerns of inequitable burdens on labor, since many of the cost reduction measures involved reducing wages or benefits of workers.     

Assessing transport related social exclusion using a capabilities approach to accessibility framework: A dynamic Bayesian network approach

Accessibility is considered to be a valuable concept that can be used to generate insights on issues related to social exclusion due to limited access to transport options. Recently, researchers have attempted to link accessibility with popular theories of social justice such as Amartya Sen's Capabilities Approach (CA). Such studies have set the theoretical foundations on the way accessibility can be expressed through the CA, however, attempts to operationalise this approach remain fragmented and predominantly qualitative in nature. In this study, a novel framework of expressing accessibility at the level of an individual is proposed, based on the basic elements of the CA. In particular, dynamic Bayesian networks are used to express the causal relationship between capabilities, functionings, personal and environmental characteristics. This is done by introducing informative Dirichlet prior distributions constructed using data from traditional mobility surveys, modelling the transition probabilities with data related to place based characteristics and defining an observation model from unlabelled mobility data and places of interest (POI). We demonstrate the usefulness of the proposed framework by assessing the equality levels and their link to transport related social exclusion of different population groups in London, using unlabelled, service provider generated mobility data.     

Distributional effects of public transport subsidies

We analyze the distribution of transit subsidies across population groups in Stockholm. We develop a novel methodology that takes into account that the subsidy per passenger varies across transit links, since production costs and load factors vary. With this, we calculate the subsidy per trip in the transit network and analyze the distribution of subsidies across population groups. The average subsidy rate in Stockholm is 44%, but the variation across trips turns out to be large: while 34% of the trips are not subsidized at all but generates a profit, 16% of the trips have a subsidy rate higher than 2/3. We calculate the concentration index to explore the distribution of subsidies across income groups. The average subsidy per person is similar for all income groups, except for the top income quintile. This holds not only for the current flat-fare system, but also for distance-based fares and fares with a constant subsidy rate. Transit subsidies is hence not effective as a redistribution policy in Stockholm. The largest systematic variation we find is across residential areas: the average subsidy per person is five times higher in the peripheral areas of the region compared to the regional core, and the subsidy per trip is ten times higher.     

Measuring railway network performance considering accessibility levels in cities worldwide

There is a growing acceptance of and interest in transit accessibility-based developments as a means to address urban challenges, such as automobile dependency, air pollution, urban sprawl, and congestion. Additionally, prompting car drivers to switch to public transit requires the construction of attractive and accessible public transit systems. Accordingly, it is necessary to measure railway network performance while considering accessibility, which indicates the potential opportunity of interaction. Thus, this study aims to develop a railway network performance index (RPI) to evaluate transit accessibility, with regard to differences in travel speed, and conduct a comparative analysis of 40 cities worldwide. The major findings are as follows. European cities have a high RPI, but cities in developing countries have relatively low RPI values, due to railway infrastructure shortages. Railway and station density have a positive relationship with RPI, but differences in RPI emerge between cities with the same infrastructure levels. This difference indicates the importance of efficient railway system connections between the distributions of populations and facilities. Overall, this study enhances understandings of transit accessibility and provides benchmark points that may be useful for decision-making processes, transportation investments, and land use policies.     

Identification and classification of public transport activity centres in Stockholm using passenger flows data

Urban geography could be characterized by analysing the patterns that describe the flows of people and goods. Measuring urban structures is essential for supporting an evidence-based spatial planning policy. The objective of this study is to examine how the spatial–temporal distribution of public transport passenger flow could be used to reveal urban structure dynamics. A methodology to identify and classify centres based on mobility data was applied to Metropolitan Stockholm in Sweden using multi-modal public transport passenger flows. Stockholm is known for its long-term monocentric planning with a dominant central core and radial public transport system. Strategic nodes along its radial public transport system have been a focus for development of sub-centres. Although the regional planning policy embraces a shift towards a polycentric planning policy, the results indicate that this has not been realized insofar.     

The spatial characteristics and influencing factors of modal accessibility gaps: A case study for Guangzhou,China

This paper presents an analysis of the spatial characteristic of the modal accessibility gap (MAG) in Guangzhou based on travel times for public transport and cars to public centers calculated by the Travel O-D point Intelligent Query System (TIQS). Four spatial regression models are used to investigate the effect on the MAG of six factors of the built environment (distance to city public centers, residential density, landuse mix, bus stop density, metro station density and road network density). The results show that travel time for a given origin to destination (OD) trip is likely to be larger by public transport than by car, especially for a trip of longer travel time. The MAG values of all the communities are larger than 0, indicating that when compared with public transport, travelling by car takes less travel time for individuals. Residential density, land-use mix, bus stop density and metro rail station density have significant negative direct impacts and indirect impacts (spatial spillover effects) on MAG, which indicates that appropriate increase in community residential density, providing diversified service facilities within a community, and improving public transport supply are beneficial to promote modal shift. Specifically, the role of metro rail is greater than that of buses. However, the road network density has significant direct positive impacts on MAG, and its spillover effect is also significantly positive, which indicates that building more roads is not an effective way to narrow the accessibility gap between public transport and cars but may facilitate more car travel instead.