Transportation Commons^™

Optimizing Multimodal Transportation Access To Support Commuting Among Low-Income Transit Riders With Social Distancing, Shailesh Chandra, Vivek Mishra

Mineta Transportation Institute

During the COVID-19 pandemic, LA Metro has encouraged social distancing among passengers—especially at stations of high-demand routes—and has increased fixed-route transit (FRT) services. However, potential impacts of social distancing on the performance of FRT services remain mostly unknown. This research evaluates the accessibility of FRT buses with social distancing using the ridership data collected on four FRT routes: 105, 108, 111, and 115 of the LA Metro's A Line stations located in low-income neighborhoods. This research shows that social distancing of six feet can impact FRT's accessibility to destination stations, and maximum accessibility is achieved only for a certain number …

Examining The Effects Of A Bike And E-Bike Lending Program On Commuting Behavior, Dillon T. Fitch, Zeyu Gao, Lucy Noble, Terry Mac

Mineta Transportation Institute

In 2015, Google added a new transportation demand management (TDM) program to increase bike commuting to their two main campuses in Mountain View and Sunnyvale, California. An initial survey of employees indicated that bike ownership and worry about maintenance were primary bicycling barriers. With this information, Google began a program that loaned high-quality electric-assisted and conventional bicycles for a period of six months at no cost to interested employees. This research evaluates the effectiveness of the program at changing travel behavior to the corporate campuses by using self-reported and smartphone-integrated travel data. The lending program at Google represents one of, …

Examining The Effects Of Precision Scheduled Railroading On Intercity Passenger And High-Speed Rail Service, John G. Green, Francis J. Miller

Mineta Transportation Institute

More than just scheduling terminal-to-terminal trips for trains, “Precision Scheduled Railroading” (PSR) creates entire point-to-point trip plans for individual railroad shipments. Since precision execution was first put into practice, the benefits to shipment arrival reliability and to freight railroads’ profitability have been demonstrated by its use in several Class One freight railroads. However, the effects of the PSR operating strategy on passenger railway operations in shared freight/passenger corridors has not been studied in detail. This research examines the effects of PSR railroad operations on passenger railways, including measuring “Host Railroad Minutes of Delay per 10,000 Train-Miles” and “On-Time Performance” of …

Heterogeneous Attentions For Solving Pickup And Delivery Problem Via Deep Reinforcement Learning, Jingwen Li, Liang Xin, Zhiguang Cao, Andrew Lim, Wen Song, Jie Zhang

Research Collection School Of Computing and Information Systems

Recently, there is an emerging trend to apply deep reinforcement learning to solve the vehicle routing problem (VRP), where a learnt policy governs the selection of next node for visiting. However, existing methods could not handle well the pairing and precedence relationships in the pickup and delivery problem (PDP), which is a representative variant of VRP. To address this challenging issue, we leverage a novel neural network integrated with a heterogeneous attention mechanism to empower the policy in deep reinforcement learning to automatically select the nodes. In particular, the heterogeneous attention mechanism specifically prescribes attentions for each role of the …

The Impact Of Ride-Hail Surge Factors On Taxi Bookings, Sumit Agarwal, Ben Charoenwong, Shih-Fen Cheng, Jussi Keppo

Research Collection School Of Computing and Information Systems

We study the role of ride-hailing surge factors on the allocative efficiency of taxis by combining a reduced-form estimation with structural analyses using machine-learning-based demand predictions. Where other research study the effect of entry on incumbent taxis, we use higher frequency granular data to study how location-time-specific surge factors affect taxi bookings to bound the effect of customer decisions while accounting for various confounding variables. We find that even in a unique market like Singapore, where incumbent taxi companies have app-based booking systems similar to those from ride-hailing companies like Uber, the estimated upper bound on the cross-platform substitution between …

Car Accidents, Smartphone Adoption And 3g Coverage, Jonathan Hersh, Bree J. Lang, Matthew Lang

Economics Faculty Articles and Research

This paper examines the relationship between smartphone use by drivers and traffic accidents in California between 2001 and 2013. In order to estimate smartphone use, we first show that widespread adoption of modern smartphones began in 2009 after the release of the iPhone 3G and T-Mobile G1. This information is combined with annual 3G coverage maps that are constructed from cellular tower information in a machine learning framework. In a difference-in-differences framework, we estimate the combined effect of smartphone adoption and 3G coverage along quarter-mile road segments. Controlling for census tract population density, road and year fixed effects, Poisson regression …

Webinar: Is Transit-Oriented Development Affordable For Low And Moderate Income Households?, Reid Ewing, Justyna Kaniewska

TREC Webinar Series

Transportation and land use planning, as a field, is shifting away from segregated uses connected by highways and streets to more compact, mixed-use developments connected by high-quality transit. This new paradigm has brought special attention to transit-oriented developments (TOD), which are sometimes touted as being among the most affordable, efficient places to live. But how affordable are they, and who has the power to effect change? This study examines housing costs for households living in TODs.

Oral Presentations: Social Sciences I, Olivia Maurer, Kaden Grace, Ryan Wallace

Mississippi Undergraduate Honors Conference

Video provided above is of Olivia Maurer's presentation.

Video of Kaden Grace's presentation is available here.

Video of Ryan Wallace's presentation is available here.

Reckoning With Induced Vehicle Travel, Jamey Volker

PSU Transportation Seminars

Empirical research shows that expanding roadway capacity induces more driving - the so-called "induced travel" phenomenon. However, environmental impact assessments and cost-benefit analyses of roadway capacity expansion projects have historically ignored, underestimated, or misestimated this induced travel effect. As a result, they frequently overestimate the projects' potential to relieve congestion and reduce air pollution. That spurred our team at the National Center for Sustainable Transportation (UC Davis) to develop an online tool to facilitate estimation of induced vehicle travel from capacity expansion projects. This presentation will explain the induced travel phenomenon, introduce our induced travel calculator and its offshoots, …

Is Transit-Oriented Development Affordable For Low And Moderate Income Households?, Reid Ewing, Sadegh Sabouri, Justyna Kaniewska, Hassan Ameli, Wookjae Yang, Fatemeh Kiani, Junsik Kim, Douty Chibamba

TREC Final Reports

The transportation and land use planning paradigm is shifting away from segregated uses connected by highways and roads to more compact, mixed-use developments connected by high-quality transit. This new paradigm has brought transit-oriented development (TOD) to the fore, and researchers continue to highlight advantages of this style of well-integrated land use and transportation planning. When it comes to affordability, what counts isn’t housing costs alone but the combination of housing plus transportation costs (H+T). If TODs do, in fact, command higher rents due to increased transit accessibility, this creates an issue of social equity, especially if higher housing costs are …

Understanding The Impact Of Decentralizing Homeless Services On Transportation And Mobility In Salt Lake County, Sarah L. Canham, Jeff Rose, Ivis Garcia Zambrana, Shannon O. Jones

TREC Final Reports

In 2019, the delivery of homeless sheltering services in Salt Lake County transitioned from a centralized emergency shelter—The Road Home Salt Lake Community Shelter and Resource Center (TRHSLC)—operated by The Road Home to a decentralized, scattered site model with multiple “Homeless Resource Center” (HRC) locations operated by multiple service providers. To understand to what degree and to which “proximity” to public transportation and other needed services was achieved, this study examined: 1) how the decentralization of homeless services influenced transportation demand and mobility patterns for persons experiencing homelessness (PEH); and 2) how transportation and mobility changes affected access to services …

Development Of Guidelines For Collecting Transit Ridership Data, Hong Yang, Kun Xie, Sherif Ishak, Qingyu Ma, Yang Liu

Computational Modeling & Simulation Engineering Faculty Publications

Transit ridership is a critical determinant for many transit applications such as operation optimizations and project prioritization under performance-based funding mechanisms. As a result, the quality of ridership data is of utmost importance to both transit administrative agencies and transit operators. Many transit operators in Virginia report their ridership data to the Department of Rail and Public Transportation (DRPT) and the National Transit Database (NTD). However, with no specific guidelines available to transit agencies in Virginia for collecting ridership data, the heterogeneous mixture of diverse data collection methods and technologies has often raised concerns about the consistency and quality of …

Negotiating Transportation Insecurity: Local Responses And Coping Strategies In San José, Ca, Andrew Ng, Melissa Beresford

Mineta Transportation Institute

People rely on transportation every day to access food, work, and social activities. Transportation insecurity—the lack of regular access to adequate transportation—can therefore cause significant disruptions to livelihoods. Understanding how people experience transportation insecurity in metropolitan areas may contribute to building better transportation systems and help formulate ways to alleviate persistent and underlying transportation issues. In this study, the researchers interviewed San José residents who experience transportation insecurity to better understand their experiences and identify the major ways that they cope with lack of adequate transportation. The researchers then used inductive techniques for thematic text analysis to identify patterns major …

Modeling Factors Contributing To Dockless E-Scooter Injury Accidents In Austin, Texas, Amin Azimian, Junfeng Jiao

Research Collection College of Integrative Studies

Objective: Over the past few years, increased e-scooter ridership has raised concerns about the growing number of injury accidents involving e-scooters. Additionally, given the lack of appropriate e-scooter accident data, the extent to which built environment and socioeconomic factors affect e-scooter safety is unclear. In consideration of these issues, this study was aimed at identifying the factors contributing to the number of e-scooter injury accidents in Austin. Methods: We developed zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) models on the basis of 2018 dockless e-scooter injury accident data collected from the Patch platform. The results indicated that the ZIP …

A Constraint Programming Approach To Load Capacity Planning In Container Vessels, Byung Kwon Lee, Joyce M. W. Low

Research Collection Lee Kong Chian School Of Business

A container vessel carries containers of various characteristics, in terms of size, weight, and contents. The cargo load of a container vessel, being subjected to a set of operational conditions and restrictions regarding ship stability and safety, is a fundamental element in decision-making when a shipping line provides logistics services to clients. This study presents a constraint programming-based model for the capacity planning of a container vessel under various operational conditions. The proposed model generates base solutions and is complemented with a rich scenario-based analysis that utilizes real-life ship data of a container vessel operated by a liner shipping company …

How Affordable Is Housing In Transit-Oriented Developments?, Reid Ewing, Nicole Iroz-Elardo, Arlie Adkins

TREC Project Briefs

Transportation and land use planning, as a field, is shifting away from segregated uses connected by highways and streets to more compact, mixed-use developments connected by high-quality transit. This new paradigm has brought special attention to transit-oriented developments (TOD), which are sometimes touted as being among the most affordable, efficient places to live. But how affordable are they, and who has the power to effect change?

Is Transit-Oriented Development Affordable for Low and Moderate Income Households?, a study funded by the National Institute of Transportation and Communities (NITC), examines housing costs for households living in TODs. Led by Reid Ewing …

Optimizing Housing And Service Locations To Provide Mobility To Meet The Mandated Obligations For Former Offenders To Improve Community Health And Safety, Anne Nordberg, Jaya Davis, Stephen Mattingly, Sarah R. Leat, Mansi Patel, Michael Mitchell, Santhosh Medeti, Craig Keaton, Jobaidul Boni, Jhanvi Manishkum, Alireza Fallahi, Sheida Khademi

TREC Final Reports

Roughly 2,000 inmates return to communities each day in the U.S. Unsuccessful reentry jeopardizes community safety, promotes re-incarceration, and increases costs to taxpayers to support the criminal justice apparatus. Research indicates that strong networks of support reduce recidivism, but most communities remain ill-equipped to successfully support former offenders. Our community partner, Unlocking DOORS in Dallas, TX, is a reentry brokerage firm that coordinates services including housing, mental and physical health services, job retraining, transportation, and parole or probation obligations. This, like most reentry service providers, assists former offenders navigating a patchwork of logistical hurdles including individual offender obligations, scarce offender …

Comprehensive Performance Assessment Of Passive Crowdsourcing For Counting Pedestrians And Bikes, Wen Cheng, Yongping Zhang, Edward Clay

Mineta Transportation Institute

Individuals who walk and cycle experience a variety of health and economic benefits while simultaneously benefiting their local environments and communities. It is essential to correctly obtain pedestrian and bicyclist counts for better design and planning of active transportation-related facilities. In recent years, crowdsourcing has seen a rise in popularity due to the multiple advantages relative to traditional methods. Nevertheless, crowdsourced data have been applied in fewer studies, and their reliability and performance relative to other conventional methods are rarely documented. To this end, this research examines the consistency between crowdsourced and traditionally collected count data. Additionally, the research aims …

A Geographical Contribution On Interurban Passenger Rail Transportation In The United States, Matthieu Schorung

Mineta Transportation Institute

Why does the rail infrastructure of the United States lag behind those of many other developed countries? Where is U.S. high-speed rail? This research approaches this in a dilemma by exploring Amtrak’s traditional rail services and high-speed rail projects in the nation to understand the workings of public rail transportation policies, what they contain, and how they are developed and pursued by the different stakeholders. This research utilizes case studies and a multiscale approach to analyze the territorialization of intercity rail transportation policies. The analysis demonstrates the emergence of a bottom-up approach to projects, notably apparent in the California HSR …

Rural Pregnant Women’S Experiences With Substance Use Disorder: A Qualitative Study, Cami Weber

Dissertations

Rural pregnant women with substance use disorder (SUD) are an understudied vulnerable population that often experiences poor pregnancy outcomes (Higgins et al., 2019; Jumah, 2016; Kramlich et al., 2018; Shaw et al., 2015). Despite the high prevalence and high burden associated with SUD, rural women are less likely than non-pregnant women to seek addiction treatment and complete an outpatient treatment program during pregnancy (Shaw et al., 2015). This study aimed to give voice to rural Missouri women with SUD. The research questions explored the life experiences and motivations for seeking treatment using a qualitative, descriptive research design with grounded theory …