Transportation Equity Research Articles

Exploring the Spatial Patterns of Accessibility to Metro Services Considering the Locations of Station Entrances/Exits

Accessibility to metro services is often evaluated based on the locations of stations. However, compared to the location of station itself, focusing on its entrances/exits offers a more accurate approach to assessing station supply and demand levels. Despite this, research focusing on the supply of and demand for metro services concerning metro entrances and exits remains limited. This study employed multi-source geospatial data from Xiamen, China, to examine the supply and demand dynamics of metro stations with a particular emphasis on entrances/exits. In the first phase, we treated entrances/exits as supply facilities and used land plot boundaries as the fundamental spatial units for accessibility calculations. Taking into account the layout characteristics of entrances/exits, along with the traffic generation of various land-use types, we employed the Gaussian two-step floating catchment area (G2SFCA) method to gauge the supply and demand levels of plots. Subsequently, we computed the spatial supply-and-demand relationships of station entrances/exits for both station-level and shared usage level of entrances/exits. We found that the accessibility from plots to entrances/exits diverged from previously observed spatial distribution trends, being higher in city centers, regional boundaries, and terminal stations and lower in transitional areas. Moreover, “metro accessibility” and the “imbalance index of entrances/exits” are associated with the primary functions of stations and the surrounding urban development; yet they exhibit spatial heterogeneity. The stations with a high value for “imbalanced index of entrances/exits” were always near some business parks, and “metro accessibility” seemed to be more easily affected by location factors. Based on two metrics, stations were categorized into four types, each displaying unique characteristics regarding location distributions, entrance/exit configurations, and commuting passenger sources. This research aims to identify the phenomenon of unfair transport in metro service from the perspective of their entrances, inform the optimization of metro station designs, and tailor planning recommendations, ultimately enhancing transport equity and contributing to sustainable urban built environments.

Do affluent neighbourhoods pay more for transit access? Exploring the capitalization of employment accessibility within different housing submarkets in Vancouver

Decades of research indicate that accessibility plays a fundamental role in the urban systems of cities by influencing land markets and household location choices. Accessibility is also often positioned as a policy tool in enhancing the well-being of disadvantaged population groups. Considered together, recent research into transportation equity underscores the need to critically investigate the distribution of accessibility with their affordability impacts. To better understand this dynamic, this research assesses variability in the relationship between employment access and house prices within different neighbourhood types in Metro Vancouver. We first calculate network accessibility to employment opportunities. Next, to integrate equity, we use sociodemographic indicators from census data to establish a typology of four neighbourhoods: Affluent, Stable Middle-class, At-Risk Middle-class and Economically-disadvantaged. Finally, using real estate data, we employ spatial econometric models to estimate differences in the capitalization of accessibility in residential property prices across these neighbourhood types. Results suggest that the value of transit access does differ by neighbourhood type in Metro Vancouver. While more affluent neighbourhoods exhibit the highest marginal willingness to pay for accessibility, predicted prices are highest in disadvantaged neighbourhoods due to their higher absolute levels of access. The research offers new insight into how property price effects vary according to different accessibility and sociodemographic contexts, and highlights important implications for both policy and future research.

Assessing spatial and racial equity of subway accessibility: Case study of New York City

Enhancing the utility of public transportation through easy and equitable access has become one of the focal points in the pursuit of social justice goals. This study aims to provide a comprehensive analysis of equitable access to the subway system in New York City (NYC) based on geography and race/ethnicity, shedding light on the complex relationship between transportation equity, racial diversity, and urban dynamics. New York City is selected as the case study due to its diverse demographic makeup, extensive public transportation system, and paucity of previous research on the racial justice dimensions of its subway system. Gravity index is employed to investigate the accessibility of the NYC subway system in terms of distance from stops and the frequency of service while equity is analyzed by Gini coefficients and Lorenz curves. To conduct this analysis, American Community Survey (ACS) data and The General Transit Feed Specifications (GTFS) are used. The findings reveal that accessibility to the subway system varies across New York City's outer boroughs, with Queens, the largest borough by area, notably standing out due to its limited availability of subway stations. Moreover, the study uncovers stark racial disparities in accessibility within boroughs, with the non-Hispanic Black community in Queens (which represents 17 % of the borough's population) facing a pronounced lack of easy access to subway stations. These insights underscore the urgent need for targeted interventions and policy reforms to address the identified disparities. Policymakers and transportation planners should prioritize initiatives such as increasing subway infrastructure in underserved areas, improving the frequency of service, and enhancing connectivity to reduce racial and spatial inequities in subway accessibility.

Collecting population-representative bike-riding GPS data to understand bike-riding activity and patterns using smartphones and Bluetooth beacons

Bike-riding GPS data offers detailed insights and individual-level mobility information which are critical for understanding bike-riding travel behaviour, enhancing transportation safety and equity, and developing models to estimate bike route choice and volumes at high spatio-temporal resolution. Yet, large-scale bicycling-specific GPS data collection studies are infrequent, with many existing studies lacking robust spatial and/or temporal coverage, or have been influenced by sampling biases leading to these data lacking representativeness. Additionally, accurately detecting bike-riding trips from continuously collected raw GPS data without human intervention remains a challenge. This study presents a novel GPS data collection approach by leveraging the combination of a smartphone application with a Bluetooth beacon attached to a participant’s bike. Aided by minimal heuristic post-processing, our method limits data collection to trips taken by bike without the need for participant intervention, carefully optimising between survey participation, privacy challenges, participant workload, and robust bike-riding trip detection. Our method is applied to collect 19,782 bike trips from 673 adults spanning eight months and three seasons in Greater Melbourne, Australia. The collected dataset is shown to represent the underlying adult bike-riding population in terms of demographics (sex, occupation and employment type), temporal and spatial patterns. The average trip length (median = 4.8 km), duration (median = 20.9 min), and frequency of bicycling trips (median = 2.7 trips/week) were greater among men, middle-aged and older adults. The ‘Interested but Concerned’ riders (classified using Geller typology) rode more frequently, while the ‘Strong and Fearless’ and ‘Enthused and Confident’ groups rode greater distances and for longer. Participants rode on roads/streets without bike infrastructure for more than half of their trips by distance, while spending 24% and 17% on off-road paths and bike lanes respectively. This population-representative dataset will be key in the context of urban planning and policymaking.

Social-Ecological Urbanism as a Research Perspective to Analyse Transportation Inequalities in the Region of Łódź, Poland

The systems perspective enables the understanding of complex transformations which take place in urban regions. Social-ecological urbanism is an analytical methodology that integrates the systems perspective and unpacks relationships between the social-ecological and socio-technical subsystems of urban regions. In this article, we look for the most suitable approach to analysing the transformations of a tramway system and its impacts on public transportation inequalities in the metropolitan region of Łódź, Poland. As a departure point, we use the classic methods of communicative planning theory. The presented method uses a detailed case study analysis that carefully follows all the activities, stakeholders, and processes. We complement this approach by looking at the ongoing transformations of transportation equity through the lens of socio-ecological urbanism and by analysing the stakeholders’ roles and attitudes within the process. Our analysis indicates the role of public participation in the process, which affected and strengthened the transformations. This approach is greatly enhanced by the application of the social-ecological urbanism framework, with its analysis of services performed by various system components. Understanding their specific roles helps in planning future redevelopment. Our key finding is the necessity of combining communicative planning methods with strategic planning of the systems transformation process.

Does built environment improvement promote transport equity for internal migrants in Beijing?

Numerous studies and practices leverage improvements in the built environment to encourage green transportation due to its significant potential to shape travel behaviors. Yet, the equity impacts of these improvements on vulnerable populations remain underexplored. This study seeks to address the question: whether built environment improvement strategies advance transport equity? Using a travel survey from Beijing and combining the Capability Approach with the Random Parameter Logit model, we develop a multilevel discrete choice model to estimate capability changes for four hypothetical scenarios of built environment improvement and conduct transportation equity analysis using Maximax principle. Our results show that increasing the mix of land use is prioritized to enhance commuting equity for carless internal migrants. Expanding bus route coverage is recommended to alleviate commuting inequality for low-income internal migrants. However, increasing road density or decreasing the distance to the nearest metro station may not effectively mitigate commuting inequities for disadvantaged internal migrants.

Understanding the relationship between perceived accessibility, housing and transport equity of different types of residents: A structural equation modelling approach

This study uses structural equation modelling (SEM) to analyse the relationship between perceived accessibility, housing and transport equity and their influencing factors in Nanjing, China. It aims to address the current shortfall in studies to compare differences in perceived (rather than objective) measures of accessibility using a transport equity lens. A comparison sample of 664 affordable housing residents and 828 commercial housing residents living in different locations across the city was collected through an online survey. The research shows that affordable housing residents are in a more disadvantaged position than commercial housing residents based on their perceived accessibility, housing and transport equity evaluation results are all worse than those of commercial housing residents. Therefore, two SEM models were constructed to understand the underlying factors driving these perceptions. The results show that both housing location and transport provision significantly affect perceived accessibility, housing and transport equity. Improving people’s transport affordability is the most effective way to improve perceived accessibility, and transport equity for both groups, however, improving the housing environment is more critical for affordable housing residents, while improving housing affordability is more important for commercial housing residents.

Toward A Comprehensive Framework for Accessibility Measures for Movement-Challenged Persons

Access is one of the most important rights for persons with disabilities (PWDs), particularly for movement-challenged persons (MCPs). To adopt appropriate policy measures that ensure this right for MCPs, it is necessary to evaluate accessibility appropriately. There are, however, very few accessibility measures applicable to MCPs. The current study proposes a framework for a novel comprehensive accessibility measure for MCPs (CAMMCP) by integrating parameters of universal design and the impact of mode-specific challenges faced by MCPs with existing accessibility measures following an origin-to-destination approach. The study presents a literature review of existing accessibility measures and suggests approaches to modify measures to suit mobility challenges faced by MCPs. Modified accessibility measures have been integrated with other parameters related to universal design and mode-specific problems. Universal-design-related parameters will include ramp slope and curb cuts, which can be measured through physical survey. Information on the impact of mode-specific challenges to MCP accessibility can be collected through questionnaires and participatory survey methods. The study also suggests approaches to modifying existing accessibility measures that do not differentiate between mobility constraints for MCPs and non-MCPs when evaluating accessibility. CAMMCP will be helpful for transportation policymakers taking the initiative to improve built-environment accessibility for MCPs as well as for evaluating projects through the lens of transport equity. It can be particularly helpful in determining walkability and transit-service accessibility. Hopefully, it will help build better road networks and transportation modes to develop a sustainable and inclusive transportation system.

Synergizing shared micromobility and public transit towards an equitable multimodal transportation network

This paper assesses the equity impacts of shared micromobility and investigates regulatory policies that improve transport equity and promote synergy between public transit and shared micromobility. We consider a multimodal transportation network, where a micromobility platform deploys docking stations and operates a fleet of micromobility vehicles to provide shared micromobility services and a public transit agency offers transit services over a transportation network. A market equilibrium model is developed to capture the intimate interactions among access and egress times of shared micromobility services, waiting times of transit services, the spatial distribution of docking stations, passenger demand, platform pricing and fleet sizing, vehicle repositioning and the micromobility platform profit. The platform decision problem is cast as a high-dimensional non-convex program. A solution method is proposed to efficiently compute the solution through problem reformulation and dimensionality reduction. Based on the proposed framework, we evaluate spatial equity in transport accessibility using the Gini index, and find that although shared micromobility improves overall transport accessibility, the benefits are not fairly distributed across different geographic zones, which leads to enlarged spatial inequity gaps after introducing shared micromobility. To promote transport equity, we investigate three policy directions: (a) to impose a vehicle density floor on shared micromobility; (b) to offer a subsidy on shared micromobility rides for first/last-mile connections; and (c) to promote collaboration between public transit and shared micromobility. We show that different regulatory policies have advantages and limitations. The minimum vehicle density requirement can simultaneously improve spatial equity and passengers’ surplus, but has limited equity improvements. In contrast, the subsidy on bundled services could significantly mitigate spatial inequity, but it hurts passengers and the platform profit. Compared to the other two policies, the transit-micromobility collaboration can lead to higher equity improvement, higher passenger surplus, while offering a guarantee on the platform profit, which turns out to be the most cost-effective approach. These insights are validated through realistic numerical studies for San Francisco.

Developing two-dimensional indicators of transport demand and supply to promote sustainable transportation equity

Inadequate supply of transport infrastructure is often seen as a barrier to a sustainable future for cities globally. Such barriers often perpetuate significant inequalities in who can and who cannot benefit from sustainable transport opportunities, and as a result there is momentum for transformative urban planning to promote sustainable transportation equity. This study introduces a new set of two-dimensional indicators, merging elements of supply and demand, to identify barriers and imbalances in sustainable transport equity. The accessibility indicators, which are generated for bus, rail, and cycle infrastructure, consider the proximity of administrative areas to good quality transport infrastructure, as well as mode-specific demand, to clearly identify areas where the supply of infrastructure is inadequate to support local populations. We present a policy case study for Liverpool City Region, which demonstrates how these indicators can be used in an analytical framework to support transformative urban planning in long-term. In particular, the indicators reveal policy priority areas where demand for sustainable transport is greater than supply, as well as neighbourhoods where multiple transport inequalities are intersecting spatially, highlighting the need for specific types of infrastructure investment to promote sustainable transport equity (e.g. more frequent services, additional cycle paths). Our framework lays the foundations for improved decision-making in urban systems, through development of mode-specific sustainable transport indicators at small area levels, which harmonise elements of supply and demand for the first time.

Accessibility to the winter cycling network in Montréal: A transport equity diagnosis

Recent studies have demonstrated the importance of a well-maintained and safe bicycle network to increase winter cycling. However, inequities in the access to cycling infrastructure in winter have not been documented yet. Based on the concept of equity in transport, this research aims to fill the gap and assess whether inequities are exacerbated during winter in the city of Montréal, Canada. The distance to the nearest cycling network section and kilometres of cycling network with 2.5 km and 5 km were computed in GIS. Two types of statistical analysis were then conducted to assess potential inequities for four population groups: weighted t-tests and seemingly unrelated regression (SUR) models. Our results demonstrate that the winter cycling network is more concentrated in central neighbourhoods and that accessibility issues are increasing in winter. Visible minorities face the most lack of accessibility, compared to the rest of the population. People under the age of 15 and over the age of 65 years old are also in unequal situations, while the low-income population has better access to winter cycling infrastructure than other groups. Our results innovate by incorporating measures of accessibility to the winter cycling network into the assessment of transport inequities.

Impact of Zoning Regulations on Transportation Equity of Job Accessibility: A Spatial Autoregressive Approach for the Dallas–Fort Worth and Houston-Galveston Area Council Areas

Impact of Zoning Regulations on Transportation Equity of Job Accessibility: A Spatial Autoregressive Approach for the Dallas–Fort Worth and Houston-Galveston Area Council Areas

Spatial effects of carbon pricing on transport equity

There is an ongoing process that greenhouse gas emissions of transport will be incorporated in the European Emissions Trading System. The cap-and-trade approach will result in substantial price increases for fossil fuels which will affect affordability of the transport systems. Within this paper the regressive effect on car-owning households is described in different area categories of the urban and rural region in Germany. Equal-per-household redistribution of the carbon revenue could reverse the regressive effect into a progressive effect. However, there is substantial variation within the different economic status groups leaving notable shares of households with a very low economic status without a positive net transfer. This share will be lowest in the metropolises of the urban region and highest in small-sized cities/village areas of the urban and rural region. Particularly in the latter area categories, these households may need temporary mobility allowances due to limited abatement options. Despite the environmental bonus, electric car-owning households still belong to groups of higher economic status, and public transport supply is limited, particularly in the small-sized cities/village areas of the urban and rural region.

Multi-group exploration of the built environment and metro ridership: Comparison of commuters, seniors and students

Understanding the associations between demographic groups’ metro travel behaviors and the built environment is crucial for addressing automobile dependence and promoting transportation equity and reasonable urban construction. This study examines the nonlinear relationships and threshold effects of the built environment on the metro travel patterns of three groups (i.e., commuters, seniors, and students) by applying smart card data in Kunming, China. We select the optimal machine learning model—gradient boosting decision trees (GBDTs)—and consider various built environment attributes. Our findings indicate that: 1) built environment attributes universally have nonlinear and threshold effects on metro travel for all groups; 2) the collective contributions of density and diversity differ greatly across groups compared to other attributes; and 3) only a few built environment attributes have similar effect directions and degrees across all three groups, while most have unique effects on each group. The findings suggest metro station area planning strategies to promote metro use and transportation equity for different groups.

Nonlinear impact of built environment on people with disabilities’ metro use behavior

Ensuring equal access to public transportation for people with disabilities is crucial for social equity and sustainable urban development. The physical characteristics and travel preferences of people with disabilities may lead to unique spatial and temporal characteristics of metro use behavior and make them more likely to be influenced by built environment characteristics. We tested this hypothesis by comparing metro travel behavior in Wuhan, China, for people with and without disabilities. The results showed that people with disabilities take more and shorter metro trips than people without disabilities. The relative importance of built environment features in influencing metro ridership displays notable distinctions between people with disabilities and those without, as indicated by the outcomes of the gradient boosting decision tree (GBDT) model. For metro ridership among people with disabilities, street density, the number of medical facilities, and the building plot ratio are the top three influencing variables on weekdays, while the number of shopping centers, medical facilities, and recreational facilities are the top three on weekends. Additionally, these variables exhibit clear nonlinear associations on metro ridership for both groups. The findings offer new insights for providing a better travel environment for people with disabilities and thus promoting transportation equity.

Advocating for transportation equity: A critical examination of paratransit service reductions in St. Louis and its impact on health and community social participation

Social participation is associated with better health, quality of life, physical activity, and engagement in community living and is thus an emerging health priority. Transportation plays an important role in facilitating social participation. Our team recently reported in the Journal of Disability and Health that Missouri-dwelling adults aging with long-term physical disabilities who use paratransit services as their primary transportation mode are more likely to participate in social roles and activities outside the home compared to those who do not use paratransit. In March of 2023, the paratransit company Metro Call-A-Ride that serves St. Louis announced major scale backs to their coverage zones due in part to staffing shortages. This decision has been met with a formal complaint filed to the U.S. Department of Justice as well as protest from the St. Louis disability community and advocates. Thousands of individuals who relied on Call-A-Ride for their routine community outings—to work, grocery stores, or medical appointments, for example—have been affected by the cuts. In this commentary, we will summarize the media coverage this decision has received, including the perspectives of disability rights advocates and individuals who have been directly affected. We will then present an overview of our original research findings in the context of these recent events and a brief synthesis of existing literature on paratransit services in the U.S. The commentary will end with proposed policy, research, and programming solutions for St. Louis's Metro Call-A-Ride and public transportation at large.

Exploring the interconnection between telecommuting, trip reduction, and transportation equity amidst the coronavirus pandemic

ABSTRACT This study delves into the rebound effect between telecommuting and trip reduction during the pandemic, offering crucial insights for transportation policy and societal well-being amidst the rise of remote work. Drawing from data across major US cities, it assesses transportation equity among socioeconomic groups. This study corrects sampling biases with the synthetic minority oversampling technique and captures endogeneities among correlated dependent variables using multivariate mixed models. The findings underscore variations in telecommuting and trip reduction levels across cities and identify the absence of the rebound effect between telecommuting and trip reduction during the pandemic. Importantly, this study informs telecommuting practices in the endemic era, highlighting the need to prioritize equity considerations for marginalized groups such as the elderly, females, minorities, and low-income households.

Training Architects as Activists: Social Sustainably in the Studio

This paper discusses the application of social sustainability to architecture through a second-year graduate architecture studio focused on urban buildings. I designed the Urban Design Studio in such a way that future faculty could choose assignments between five socially sustainable equity issues: housing, food insecurity, transportation equity, access to opportunities, and environmental health. This supports the Rochester Institute of Technology (RIT) graduate curriculum by focusing on sustainable practices, including activism in architecture. Using the built environment as a platform, the students learn to promote equity, especially in the urban environment. The students research on equity topics, adopt a position on a selected issue, and begin to develop a site, program, and building form around their issue. Architecture has a unique ability to influence social sustainability through equity, especially if we shift our design practices to support disenfranchised populations. Buildings can provide more than social markers. They can create locations that empower local communities. The question is, how do we teach a process that instills this as foundational to quality design? My studio’s process not only establishes a foundational knowledge of building within an urban context, but also provides a firm grounding of activism as central to architectural practice.

Participatory Planning in Designing Autonomous Mobility Systems: A Design Thinking Approach

The adoption of participatory planning approaches in the deployment of new mobility solutions is rare. In this study, we conducted a community-based planning exercise using design thinking approaches to engage residents in co-creating an Autonomous Mobility System (AMS) for their neighborhood in Singapore. Through this process, a baseline understanding of participants’ attitude toward autonomous vehicles (AVs) was established, along with understanding the residents’ travel patterns and challenges. A co-creation activity guided participants to design their ideal AMS for the local community living in the Punggol residential district in Singapore. The exercise resulted in 20 unique designs of AMS, producing novel ideas such as suitable AV-holding areas and service zones. The results of the design activities provided insights into community-level priority and values. For AMS, providing alternative transport options that complemented existing train and bus services was the priority. As participants co-designed an AMS that fitted their needs as well as the needs of other participants, the designs also suggested that participants valued transport equity and accessibility, especially for the marginalized population, highlighting the importance of a human-centric design approach to transportation planning.

A case for race and space in auto ownership modeling: A Los Angeles County study

Auto ownership behavior is driven by complex relationships that can vary dramatically across different traveler groups and communities. Differences in auto ownership among racial groups have been of particular interest, given ongoing efforts to advance equity in transportation outcomes. There are a number of studies documenting racial disparities in auto ownership associated with racial and ethnic residential clustering, termed “automobile mismatch.” Yet, these differences in auto ownership behavior by race and residential location are virtually never considered in models of travel behavior, despite calls for the consideration for race in transportation planning and decision making. This study aims to bridge the gap between understandings of the connections between race and space and transportation outcomes, using Los Angeles County as a case study. A series of auto ownership model specifications are used to investigate statistical connections between the racial and ethnic categories of residents, and neighborhoods, revealing systematic variations across racial and spatial dimensions. The composite model, which includes racial and spatial indicators, outperforms the base model, suggesting that the inclusion of race and space explains significantly more information on variations in auto ownership and provides a superior fit to the data. Our findings also suggest that the exclusion of racial and spatial indicators may lead to overestimation of certain effects, and may completely misrepresent the importance of certain household, individual-level, and built environment effects in explaining auto ownership preferences. Given the increasing attention to equity and representation in transportation outcomes, models that exclude considerations for race and space may be poorly positioned to support meaningful transportation equity analyses.