Transportation Equity

Creating a Data Resource of California Police Stops for Use in Traffic Safety Applications | Safe Transportation Research and Education Center

Griswold, Julia
2025

Traffic stops are one of the most common ways in which the American public interacts with police. Although one of the leading reasons given for police traffic stops is a violation of the vehicle code, there is limited and mixed research on the impact of traditional police traffic enforcement on traffic safety outcomes. At present, few large data resources with an appropriate level of detail exist to facilitate investigations of this type. The 2015 Racial and Identity Profiling Act (RIPA) requires all law enforcement agencies in California to collect and submit vehicle (including bicycle)...

Electric Vehicles and Social Equity

Yassine, Ziad
Shaheen, Susan A.
2025

The shift toward electric vehicles (EVs) involves addressing both environmental sustainability and social equity concerns. It underscores the importance of inclusive approaches to ensure fair access to EV technology. As EVs gain traction as a sustainable transportation strategy, it is critical to address disparities in charging infrastructure, vehicle affordability, and environmental justice. There is a need to incorporate EVs into social equity frameworks that include innovative policies, community involvement, and targeted investments in underserved areas. A comprehensive approach is...

Urban and Socioeconomic Disparities in PM2.5 Exposure Across 340 Latin American Cities

Ascencio, Edson J
Barja, Anthony
Montes-Alvis, Jose M
Kephart, Josiah L.
Gouveia, Nelson
Benmarhnia, Tarik
Diez Roux, Ana V.
Bilal, Usama
Miranda, J. Jaime
Carrasco-Escobar, Gabriel
Rodríguez, Daniel A.
2025

Background: Fine particulate matter (PM2.5) is a leading global health risk. Latin American cities exhibit some of the world's highest urban PM2.5 levels, yet studies on neighborhood-level PM2.5 exposure and associated disparities in the region are limited. Methods: We conducted a cross-sectional ecological analysis of 53,041 neighborhoods across 340 cities in eight Latin American countries, leveraging the SALURBAL dataset. Annual PM2.5 concentrations were derived from satellite data and linked to socioeconomic and urban characteristics. A multilevel model analyzed associations between...

Leveraging Commuting Patterns and Workplace Charging to Advance Equitable EV Charger Access

Wang, Ruiting
Kwon, Ha-Kyung
Jordan, Katherine H.
Moura, Scott
Boloor, Madhur
Machala, Michael L.
2026

This study introduces a framework for improving accessibility to and quantifying social equity priorities in electric vehicle charging infrastructure through strategic workplace charger placement. We develop a customizable equity evaluation model that quantifies access disparities across demographic groups. This model is used to construct an optimization framework that informs charging infrastructure deployment decisions. Leveraging commuting patterns, we demonstrate in the case study of Oakland, California that strategically placing workplace charging can achieve, on average, a 1.8-fold...

Pedal Power: Operational Models, Opportunities, and Obstacles of Bike Lending in North America

Shaheen, Susan
Wolfe, Brooke
Cohen, Adam
2025

Bike lending offers a service that enables individuals to borrow bicycles for short-term use (i.e., ranging from 2 hours to 36 months), typically from designated locations within cities, campuses, or communities. Unlike bikesharing systems that typically rely on automated kiosks and/or undocked and free-floating devices for public access, bike lending involves a managed program with staff, similar to a library model. These programs can be administered by community organizations, bike shops, public libraries, and other local entities. They are typically community- or membership-based, with...

Why do Immigrants Drive Less? Confirmations, Complications, and New Hypotheses from a Qualitative Study in New Jersey, USA

Chatman, Daniel G.
Klein, Nicholas J.
2013

Recent immigrants to the United States drive autos less than the US-born, with rapid increases in their ownership and use of autos over time, and a persistently lower level of auto use even when controlling for socioeconomic characteristics and time in the US. Quantitative studies have not yet explained these phenomena. Given that population growth in the US is largely dependent on immigration, understanding auto ownership and use among immigrants is important for transportation sustainability. We conducted six focus groups with US residents born in India, the Philippines, and Latin...

Use of App-based Ridehailing Services and Conventional Taxicabs by Adults with Disabilities

Cochran, Abigail L.
Chatman, Daniel G.
2021

App-based ridehailing services such as Uber and Lyft are growing rapidly and serving more trips in large U.S. cities than conventional taxicabs, on which people with disabilities have historically depended. Analyzing the 2017 National Household Travel Survey, we found that adults with disabilities use app-based ridehailing at a much lower rate than adults without disabilities. This is partly because people with disabilities are older, have lower incomes, and live less in larger cities. But even when controlling for these factors, having a disability predicts lower use of app-based...

Immigration, Income, and Public Transit Perceptions: Findings from an Intercept Survey

Barajas, Jesus M.
Agrawal, Asha Weinstein
Chatman, Daniel G.
2018

Although a significant fraction of public transit riders in the United States are immigrants, relatively little research explores whether immigrants have unique transit experiences. This paper analyzes intercept survey data from 1,247 transit riders in the San Francisco Bay Area to explore how mode choices and travel experiences differ for low-income immigrants compared to higher-income immigrants and US-born residents. We find that some public transit experiences are similar across all immigrant status and income groups, while in other ways low-income immigrants differ from their higher-...

Immigrants and Automobility in New Jersey: The Role of Spatial and Occupational Factors in Commuting to Work

Chatman, Daniel G.
Klein, Nicholas
Lucas, Karen
Blumenberg, Evelyn
Weinberger, Rachel
2011

This chapter presents an overivew and analysis of occupational, spatial, and commuting-mode choices of immigrants to the state of New Jersey.

Exploring Bicycle and Public Transit Use by Low-Income Latino Immigrants: A Mixed-Methods Study in the San Francisco Bay Area

Barajas, Jesus
Chatman, Daniel
Agrawal, Asha
2016

Latin American immigrants will continue to make up a large share of transit ridership, bicycling and walking in the United States for the foreseeable future, but there is relatively little research about them. This mixed-methods study compares the travel patterns of low-income immigrants living in the San Francisco Bay Area with that of other groups and investigates the barriers and constraints faced by low-income immigrants when taking transit and bicycling. Much of the previous work on immigrant travel has relied on national surveys and qualitative analysis, which underrepresent...