Recent itsdavis_3rev_reports items

Barriers to Reducing the Carbon Footprint of Transportation Part 1: Support to the Clean Miles Standard Policy Making

Tue, 28 Jan 2025 00:00:00 +0000

Transportation Network Companies (TNCs), also referred to as ridehailing companies, have experienced rapid growth in the past decade. This report focuses on the quickly evolving transportation patterns resulting from the adoption of ridehailing as part of the efforts accompanying the implementation of the Clean Miles Standard (CMS) regulation. Based on the analysis of survey data collected in four California metropolitan regions before the COVID-19 pandemic, this report summarizes the findings from three studies, focusing on (1) the use of ridehailing among traveler groups with different multimodal travel patterns, (2) the substitution of ridehailing for other modes, and travel induced by ridehailing, and (3) the use of pooled ridehailing services, in which multiple passengers share the same vehicle for all or a portion of their trips. The results from these analyses reveal that transit users are more likely to be ridehailing users. Individuals without a household vehicle and...

Air Travelers’ Ground Transportation Choices at Four Airports in Northern California

Sun, 17 Nov 2024 00:00:00 +0000

Prior studies of travel mode choice in airport ground transportation identified several important relationships between traveler/trip attributes and the selected ground access mode(s). However, those studies did not comprehensively account for qualitative aspects of ground access mode choice, such as general and transportation-specific attitudes and perceptions of mode-specific airport infrastructure. To add insights into air travelers’ ground transportation choices, this study collected a dataset with a survey administered among travelers using four major airports in Northern California in the post-pandemic era.Among the analyses presented in the report, airport ground access mode choice was analyzed, and its relationships with travelers’ socio-demographics, attitudes toward transportation and related topics (e.g., environmental friendliness), and opinions about transportation infrastructure and services (e.g., airport parking fees). The authors identified relationships between...

Barriers to Reducing the Carbon Footprint of Transportation Part 2: Investigating Evolving Travel Behaviors in the Post-Pandemic Period in California

Mon, 5 Aug 2024 00:00:00 +0000

During the early months of the pandemic, stay-at-home orders and concerns about infection catalyzed a shift toward online activities, such as remote work and e-shopping, resulting in a significant decrease in conventional travel. However, as the effects of the pandemic diminished, the pandemic-induced online activities began to subside, and conventional travel started to rebound. The challenge among transportation planners and policymakers is to determine the lasting effects of the pandemic and adjust the policies accordingly. In the same efforts to understand the evolving travel-related activities and inform policymaking, the 3 Revolutions Future Mobility Program at the University of California, Davis, conducted four waves of mobility surveys between Spring 2020 and Fall 2023. Key findings from the analysis of these data reveal that remote work and a combination of remote work and physical commuting (i.e., hybrid work) emerge as an enduring outcome of the pandemic. The pandemic...

If Pooling with a Discount were Available for the Last Solo-Ridehailing Trip, How Much Additional Travel Time Would Users Have Accepted and for Which Types of Trips?

Fri, 12 Jan 2024 00:00:00 +0000

Pooled trips in private vehicles, or pooling, can lead to smaller environmental impacts and more efficient use of the limited roadway capacity, especially during peak hours. However, pooling has not been well adopted in part because of difficulties in coordinating schedules among various travelers and the lack of flexibility to changes in schedules and locations. In the meantime, ridehailing (RH) provides pooled services at a discounted fare (compared to the single-travel-party option) via advanced information and communication technology. This study examines individuals’ preferences for/against pooled RH services using information collected among travelers answering a set of questions related to their last RH trip. In doing so, both trip attributes and rider characteristics are considered. Taste heterogeneity is modeled in a way that assumes the presence of unobserved groups (i.e., latent classes), each with unique preferences, in a given sample of RH riders (N=1,190) recruited...

Investigating the Temporary and Longer-term Impacts of the COVID-19 Pandemic on Mobility in California

Tue, 27 Jun 2023 00:00:00 +0000

This study investigates how the COVID-19 pandemic has transformed people’s activity-travel patterns, using datasets collected through three waves of surveys in spring 2020, fall 2020, and summer 2021. With this dataset, it was possible to investigate evolving behavioral choices and preferences among respondents at different timepoints: fall 2019 (recollection of the past), spring 2020, fall 2020, summer 2021, and summer 2022 (future expectations). The study highlighted a large shift among California workers from physical commuting to working remotely in 2020, which was followed by a transition towards hybrid work by summer 2021. The shift to remote work and hybrid work varied considerably across population subgroups, and was most popular among higher-income, better-educated individuals, and urban residents. In terms of household vehicle ownership change, those tech-savvy and variety-seeking individuals were more likely to increase or replace household vehicles, while those...

Challenges Faced by People with Disabilities in Public and Active Transportation Systems in the United States of America

Wed, 22 Mar 2023 00:00:00 +0000

A significant fraction of people with disabilities in the United States of America (US) do not drive, and these people disproportionately use public transit and paratransit services compared to drivers with disabilities. Substantial research exists regarding not only the ease for people with disabilities to use public transit and paratransit services but also the availability of such services and the availability of nearby pedestrian infrastructure. However, much less research exists regarding the effects of shared micromobility services, car-free areas, and consolidation of public transit services on the mobility of people with disabilities. This systems-level thinking about not only first-order effects but also second- and higher-order effects is critical for the development of policies that more effectively address the mobility needs of people with disabilities.

Challenges Facing People with Disabilities in Private Vehicular Transportation in the United States of America

Thu, 16 Mar 2023 00:00:00 +0000

The majority of people with disabilities in the United States of America (US) are licensed drivers or use transportation modes based on private vehicles. Despite this, people with disabilities, including licensed drivers, still often encounter difficulties that limit their overall mobility and quality of life. Research about the problems with private vehicular modes facing people with disabilities remains sparse. Existing research suggests that some disabilities make driving impossible, while poverty often associated with disability makes owning and modifying vehicles to fit users’ needs unaffordable. People with disabilities who cannot drive or cannot afford to own a vehicle may use rental cars or carsharing services, get rides from friends or family, or use ridehailing services or taxis, but car-oriented land use patterns and the higher costs of modified vehicles together may compromise the availability of these modes for people with disabilities. Better understanding of the...

The Pulse of the Nation on 3 Revolutions: Annual Investigation of Nationwide Mobility Trends

Fri, 21 Oct 2022 00:00:00 +0000

This study investigates the disruptive changes brought to transportation by emerging technologies and the COVID-19 pandemic through the analysis of repeated cross-sectional datasets that were collected with multiple survey waves administered in various regions of the United States and Canada. The first data collection was administrated in 2019 through the recruitment of respondents with an online opinion company. As the COVID-19 pandemic started to disrupt the world starting in 2020, two additional rounds of data collection were carried out in Spring 2020 and Fall 2020, to study the disruptions in activity and travel patterns that were caused by the pandemic. Starting in 2020, the data collection was extended to 15 U.S. regions: Los Angeles, Sacramento, San Diego and San Francisco in California; Atlanta, Boston, Chicago, Denver, Detroit, Kansas City, New York, Salt Lake City, Seattle, Tampa and Washington D.C. in other U.S. regions. In addition, the study covered also Toronto...

Travel Demand Modeling Methodology Recommendations for the Link21 Program

Tue, 10 May 2022 00:00:00 +0000

This project aims to provide recommendations on the methodology and design specifications for the travel demand model to be built for the Link21 program in the Northern California megaregion. The Link21 program is a major rail investment program that will considerably improve and upgrade the passenger rail services in the Northern California megaregion, centered around the Transbay Corridor between Oakland and San Francisco in the San Francisco Bay Area. To support this effort, we reviewed the current and potential travel markets for the Link21 program, assessed the available travel demand models that could be used to support the modeling efforts for the Link21 program, and conducted interviews with experts from academic institutions, metropolitan planning organizations, state and federal agencies, and US DOE national labs. Considering the goals and objectives of the Link21 program, a list of 20 critical, important, and optional modeling features were identified, which should...

Panel Study of Emerging Transportation Technologies and Trends in California: Phase 2 Findings

Fri, 3 Dec 2021 00:00:00 +0000

Emerging transportation services, whose development and adoption have been enabled by information and communication technology, are largely transforming people’s travel and activity patterns. This study investigates the emerging transportation trends and how they transform travel-related decision-making in the population at large through the application of a unique longitudinal approach. As part of this project, a second wave of data collection in 2018 was built with a rotating panel structure as a continuation of the research efforts that started with the collection of the 2015 California Millennials Dataset. This report focuses on the analyses of the data collected in this project, in particular on the differences in attitudes towards transportation and the environment among different generational groups, the adoption and use of shared mobility services, and their relationship with vehicle ownership, the interest in the adoption of alternative fuel vehicles, and the interest...

Emissions Impact of Connected and Automated Vehicle Deployment in California

Fri, 2 Jul 2021 00:00:00 +0000

This study helps understand how the anticipated emergence of autonomous vehicles will affect various aspects of society and transportation, including travel demand, vehicle miles traveled, energy consumption, and emissions of greenhouse gases and other pollutants. The study begins with a literature review on connected and automated vehicle (CAV) technology for light-duty vehicles, the factors likely to affect CAV adoption, expected impacts of CAVs, and approaches to modeling these impacts. The study then uses a set of modifications in the California Statewide Travel Demand Model (CSTDM) to simulate the following scenarios for the deployment of passenger light-duty CAVs in California by 2050: (0) Baseline (no automation); (1) Private CAV; (2) Private CAV + Pricing; (3) Private CAV + Zero emission vehicles (ZEV); (4) Shared CAV; (5) Shared CAV + Pricing; (6) Shared CAV + ZEV. The modified CSTDM is used to forecast travel demand and mode share for each scenario, and this output is...

Longitudinal Analysis of COVID-19 Impacts on Mobility: An Early Snapshot of the Emerging Changes in Travel Behavior

Thu, 25 Feb 2021 00:00:00 +0000

Longitudinal Analysis of COVID-19 Impacts on Mobility: An Early Snapshot of the Emerging Changes in Travel Behavior

Designing Robo-Taxis to Promote Ride-Pooling

Mon, 17 Aug 2020 00:00:00 +0000

Robo-taxis (automated vehicles operating in a ride-hailing model) have the potential to improve mobility while reducing traffic, emissions, and energy use. However, such outcomes depend largely on increasing riders per vehicle. Public policy that incentivizes industry to design robo-taxis to support ride-pooling may be critical to achieving positive outcomes. This research reviews current shared automated vehicle designs and literature related to potential consumer risks and benefits of ride-pooling in robo-taxis in order to articulate potential design solutions to promote pooling.

What Affects Millennials’ Mobility? PART II: The Impact of Residential Location, Individual Preferences and Lifestyles on Young Adults’ Travel Behavior in California

Wed, 3 Apr 2019 00:00:00 +0000

Young adults (“millennials”, or members of “Generation Y”) are increasingly reported to have different lifestyles and travel behavior from previous generations at the same stage in life. They postpone the time at which they obtain a driver’s license, often choose not to own a car, drive less if they own one, and use alternative non-motorized means of transportation more often. Several explanations have been proposed to explain the behaviors of millennials, including their preference for urban locations closer to the vibrant parts of a city, changes in household composition, and the substitution of travel for work and socializing with telecommuting and social media. However, research in this area has been limited by a lack of comprehensive data on the factors affecting millennials’ residential location and travel choices (e.g. information about individual attitudes, lifestyles and adoption of shared mobility is not available in the U.S. National Household Travel Survey and most...

The Adoption of Shared Mobility in California and Its Relationship with Other Components of Travel Behavior

Fri, 15 Mar 2019 00:00:00 +0000

Emerging technologies and shared mobility services are quickly changing transportation. The popularity of these services is particularly high among millennials and those living in the dense central parts of cities. Still, the reasons behind the adoption of these services and their impacts on the use of other transportation modes and on total travel demand are largely unclear. How are shared mobility services changing transportation demand and supply? This report provides useful insights to answer this question. The research explores the use of various types of shared mobility services in California, focusing in particular on the factors affecting the adoption and frequency of use of ridehailing services (such as those provided by Uber and Lyft), and the impacts that the use of these services has on other components of travel behavior. The authors analyze a dataset that they collected with a detailed online survey in fall 2015 as the first round of data collection in a panel...