Travel Behavior

Is electric vehicle carsharing for everyone? from activity patterns to user retention

Yassine, Ziad
Martin, Elliot
Shaheen, Susan
2025

This research explores the user dynamics of electric vehicle (EV) carsharing within underserved communities, focusing on BlueLA, a one-way station-based EV carsharing service in Los Angeles, California. This study employs a mixed-methods approach to evaluate how activity patterns differ between BlueLA member types and how membership type influences user retention rates. We conduct an exploratory data, clustering, and survival analyses, using BlueLA trip activity data, supplemented by insights from a user survey and a general population survey. Our results reveal distinct travel behaviors...

A random intercept latent transition analysis (RI-LTA) of consumer spending across online and in-person channels through the pandemic

Tahlyan, Divyakant
Mahmassani, Hani
Stathopoulos, Amanda
Said, Maher
Walker, Joan
Shaheen, Susan
2025

In this study, we utilize a latent transition analysis with random intercept (RI-LTA) framework to understand the changes to consumer spending landscape through the pandemic across various product categories and acquisition channels. Using data from 785 individuals from across United States at four different time points (pre-COVID, December 2020, March 2021, and March 2022), the presented model revealed five different behavioral classes of consumer spending and the dynamics of movement between classes as a result of the pandemic. The results from the model also revealed that the pandemic’s...

What Makes the Route More Traveled? Optimizing U.S. Suburban Microtransit for Sustainable Mobility

Pan, Alexandra
Shaheen, Susan
2025

Microtransit services that provide pooled on-demand transportation with dynamic routing have been used in low-density areas since the 1970s, but improvements to routing technology have led to a resurgence of interest in the past decade. Questions remain about the effectiveness of microtransit to serve riders in low-density, car-dependent suburban areas. Better understanding of the factors underlying microtransit ridership can improve usage of these services and shift travelers to more sustainable modes in suburban areas. We compile a database of suburban microtransit programs from 32...

In-person, hybrid or remote? Employers’ perspectives on the future of work post-pandemic

Tahlyan, Divyakant
Mahmassani, Hani
Stathopoulos, Amanda
Said, Maher
Shaheen, Susan
Walker, Joan
Johnson, Breton
2024

We present an employer-side perspective on remote work through the pandemic using data from top executives of 129 employers in North America. Our analysis suggests that at least some of the pandemic-accelerated changes to the work location landscape will likely stick; with some form of hybrid work being the norm. However, the patterns will vary by department (HR/legal/sales/IT, etc.) and by sector of operations. Top three concerns among employers include: supervision and mentoring, reduction in innovation, and creativity; and the top three benefits include their ability to retain / recruit...

Communities Are Experimenting with Microtransit to Fill Critical Gaps in Public Transit Service – What Have We Learned so Far?

Shaheen, Susan
Cohen, Adam
Wolfe, Brooke
Martin, Elliot
2024

Microtransit is a technology-enabled transit service that typically employs shuttles or vans (Figure 1) to provide on-demand transportation with dynamic routing. While many rides are dispatched and paid via a smartphone, many services also provide a telephone booking option. A few services accept cash payment and street hails (similar to taxis). Variations of microtransit can include fixed schedules and routes and larger or smaller vehicles. Typically, microtransit services are operated by or provided on behalfof a government entity or nonprofit organization, although privately operated...

Environmental Impacts of Transportation Network Company (TNC)/Ride-Hailing Services: Evaluating Net Vehicle Miles Traveled and Greenhouse Gas Emission Impacts within San Francisco, Los Angeles, and Washington, D.C. Using Survey and Activity Data

Martin, Elliot
Shaheen, Susan
Wolfe, Brooke
2024

Transportation Network Companies (TNCs) play a prominent role in mobility within cities across the globe. However, their activity has impacts on vehicle miles traveled (VMT) and greenhouse gas (GHG) emissions. This study quantifies the change in personal vehicle ownership and total miles driven by TNC drivers in three metropolitan areas: San Francisco, CA; Los Angeles, CA; and Washington, D.C. The data sources for this analysis comprise two surveys, one for TNC passengers (N = 8630) and one for TNC drivers (N = 5034), in addition to data provided by the TNC operators Uber and Lyft. The...

From Taxis to Ridehailing: Examining Gender Issues for Female Drivers and Passengers

Shaheen, Susan
Cohen, Adam
Wolfe, Brooke
Champlin, Jacob
2024

This report analyzes gender issues for female drivers and passengers of transportation network companies (TNCs) and taxis. Between August 2023 and May 2024, the researchers conducted driver and rider focus groups (n=8 drivers and n=8 passengers); a driver survey (n=170); a TNC user/non-user survey (n=440, including n=217/440 taxi non-users, n=7/440 TNC non-users, and a subset of n=5/440 non- users of TNCs and taxis); and expert interviews (n=13). This research finds that both female drivers and passengers experience an array of safety concerns and challenges traveling with young children...

What Is the Connection? Understanding Shared Micromobility Links to Rail Public Transit Systems in Major California Cities

Shaheen, Susan
Martin, Elliot
Ju, Mengying
2024

As shared micromobility (bikes and scooters) has proliferated throughout urban areas, there has been growing interest in how it facilitates connections with rail transit systems. This study explores the magnitude of interactions between shared micromobility and rail public transit systems using shared micromobility trip data and rail transit schedule data. We evaluate over one million trips from October 2019 to February 2020 in four California cities (San Francisco, Los Angeles, Sacramento, and San Jose) and develop criteria to identify trips connecting to rail transit. These include...

Effects of Cooperative Adaptive Cruise Control on Traffic Flow: Testing Drivers' Choices of Following Distances

Shladover, Steven E.
Nowakowski, Christopher
Cody, Delphine
Bu, Fanping
O’Connell, Jessica
Spring, John
Dickey, Susan
Nelson, David
2009

A Cooperative Adaptive Cruise Control (CACC) system has been developed by adding a wireless vehicle-vehicle communication system and new control logic to an existing commercially available adaptive cruise control (ACC) system. The CACC is intended to enhance the vehicle-following capabilities of ACC so that drivers will be comfortable using it at shorter vehicle-following gaps than ACC. If this is shown to be the case, it offers a significant opportunity to increase traffic flow density and efficiency without compromising safety or expanding roadway infrastructure.This report describes the...

Data Sharing of Traveler Information with the Public and Private Sectors: State of the Practice

Miller, Mark A.
Balke, Kevin
2001

This report presents the results of its examination of the current state of the practice of traveler information data sharing with the public and private sectors. A review of the literature was initially performed followed by an analysis of responses to a survey instrument that was designed and administered to practitioners in the field, primarily representatives from public sector agencies, who are in the business of collecting traveler information data. Survey results have addressed the subjects of what data is shared, with whom it is shared, why it is shared, how it is institutionally...