published journal article

Grocery shopping in California and COVID-19: Transportation, environmental justice, and policy implications

Transportation Research Part D: Transport and Environment

Abstract

To understand how COVID-19 changed grocery shopping and explore implications for transportation and environmental justice, we surveyed in May 2021 California members of KnowledgePanel®, the largest and oldest U.S. probability-based panel. We asked how frequently Californians grocery shopped before and during the pandemic, and how they may grocery shop afterward in-store, online with home delivery (“e-grocery”), or online with store/curbside pick-up (“click-and-pick”). We found that most Californians continued to grocery shop in-person during the pandemic, although less frequently than before. Many relied more on e-grocery (+8.9 %) and click-and-pick (+13.3 %), although older generations remained attached to in-store shopping. African American households grocery shopped in-store less than Whites pre-pandemic; post-pandemic, they may compensate with more e-grocery and click-and-pick. While higher levels of environmental injustice (based on CalEnviroScreen) were associated with less in-store shopping, we found no association with e-grocery or click-and-pick. Our results have implications for travel, food logistics, and parking management.

Suggested Citation
Lu Xu and Jean-Daniel Saphores (2022) “Grocery shopping in California and COVID-19: Transportation, environmental justice, and policy implications”, Transportation Research Part D: Transport and Environment, 113, p. 103537. Available at: 10.1016/j.trd.2022.103537.

working paper

Using Longitudinal Methods for Analysis of a Short-Term Transportation Demonstration Project

Publication Date

August 1, 1990

Associated Project

Author(s)

Genevieve Guiliano, Thomas Golob

Working Paper

Reprint No. 28

Areas of Expertise

Abstract

This paper documents an application of panel, or longitudinal data collection in the evaluation of a TSM (Transportation Systems Management) demonstration project. The project was a four-week demonstration of staggered work hours in downtown Honolulu during February-March 1988. The 4 wave panel survey elicited commuting experiences of approximately 2,000 downtown employees at two week intervals before and during the project. The sample involved both employees who participated in the project by shifting their work hours, and those who did not. The panel survey was augmented by floating0car observations of travel times on major routes into downtown Honolulu on the same four dates.The purpose of the analysis was to determine whether employee commute times were affected, and if so, how these changes were distributed among various employee segments. Two methods were used. First, travel time changes were estimated using paired t-tests. Second, regression equations were used to estimate project time savings as a function of trip length, route, and location of residence. Results show that travel time savings due to the project were typically small, less than ten percent. Nonparticipants experienced greater savings than participants, and some segments of participants experienced longer travel times during the project. The panel method proved to be an effective way to measure project travel time impacts and shows that the method is appropriate in short time applications.

Suggested Citation
Genevieve Guiliano and Thomas F. Golob (1990) Using Longitudinal Methods for Analysis of a Short-Term Transportation Demonstration Project. Working Paper Reprint No. 28. Institute of Transportation Studies, UC Irvine: University of California Transportation Center. Available at: https://escholarship.org/uc/item/2j98g38s.

published journal article

Tenant Riskiness, Contract Length, and the Term Structure of Commercial Leases

Management Science

Publication Date

August 29, 2025

Author(s)

Jan Brueckner, Stuart S. Rosenthal

Abstract

This paper explores the connection between tenant riskiness, commercial lease length, and the term structure of lease contracts. Theory shows that the possibility of default on a long-term lease generates a risk/lease-length connection. The empirical work uses a large CompStak lease data set combined with tenant characteristics (including risk) from Dun & Bradstreet (D&B). Regressions show that lease length is inversely related to the D&B risk measures, as predicted, and that risky tenants pay a higher rent premium for long-term contracts than low-risk tenants. The presence of such tenants thus raises the slope of the term structure of commercial rents. This paper was accepted by Tomasz Piskorski, finance. Supplemental Material: The data files are available at https://doi.org/10.1287/mnsc.2024.04959 .

Suggested Citation
Jan K. Brueckner and Stuart S. Rosenthal (2025) “Tenant Riskiness, Contract Length, and the Term Structure of Commercial Leases”, Management Science, pp. mnsc.2024.04959. Available at: 10.1287/mnsc.2024.04959.

working paper

Network Connectivity and Price Convergency: Gas Pipeline Deregulation

Publication Date

December 1, 1993

Associated Project

Working Paper

No. 202

Areas of Expertise

Abstract

We use graph theoretic methods to model arbitrage on the evolving topology of the natural gas pipeline network following pipeline deregulation. We estimate models of spot prices over the network and show that the emergence, evolution and performance of natural gas pipelines brought about by the Federal Energy Regulatory Commission’s policy of “Open Access”. Under open access, the balkanized and disconnected network of gas markets created by regulation became more strongly connected, transportation markets developed, and natural gas spot prices converged. The pace of these changes can be linked to the degree of openness and connectedness of the pipeline network; it took four years for the network to reach a critical level of connectivity to bring convergence to prices. By 1990, gas markets had become thick enough to dampen the effect of demand and supply shocks on prices at each point in the network.

Suggested Citation
Arthur De Vany and W. David Walls (1993) Network Connectivity and Price Convergency: Gas Pipeline Deregulation. Working Paper No. 202. Institute of Transportation Studies, UC Irvine: University of California Transportation Center. Available at: https://escholarship.org/uc/item/9n876133.

policy brief

Higher Bus Ridership Unlikely to Increase Community COVID-19 Transmission

Abstract

Public transportation has been blamed for facilitating the spread of COVID-19 in dense, urban areas. As a response to the COVID-19 pandemic, transit agencies have reduced service and implemented mask-wearing mandates and social distancing aboard transit. Some prior studies that address public transportation provide some evidence that negative COVID-19 outcomes are linked to high transit use. One early study of COVID-19 transmission on trains in China found that transmission is also affected by the density of passengers, seat spacing, and length of time traveled with other passengers aboard the trains.

Suggested Citation
David Brownstone and Henry Bernal (2021) Higher Bus Ridership Unlikely to Increase Community COVID-19 Transmission. Policy Brief. UC ITS. Available at: https://doi.org/10.7922/g2p26wgh.

policy brief

Shared Autonomous Mobility Services Show Promise for Increasing Access to Employment in Southern California

Abstract

Workers in Southern California currently face transportation related challenges accessing employment opportunities, including but not limited to high parking costs and/or limited parking availability in dense employment and residential areas; long commute distances between residential areas and employment opportunities; and poor transit service quality in many areas. These challenges are particularly burdensome for low-income households that may not have access to a personal vehicle and/or live in job-poor neighborhoods, as having a personal vehicle may be the only viable way to get to work.

Suggested Citation
Arash Ghaffar, Michael Hyland, Navjyoth Sarma, Suman Mitra and Tanjeeb Ahmed (2020) Shared Autonomous Mobility Services Show Promise for Increasing Access to Employment in Southern California. Policy Brief. UC ITS. Available at: https://doi.org/10.7922/g24f1p14.

working paper

The Impacts of Motor Vehicle Operation on Water Quality: A Preliminary Assessment

Abstract

Environmental studies of motor vehicles typically focus on air pollution or noise, but ignore water pollution. In this paper, we examine some of the impacts of motor vehicle transportation on non-point source and on groundwater pollution. Our estimates of the present value of costs for cleaning up leaking underground storage tanks and for controlling highway runoff for major arterials range from $45 billion to $235 billion, which is at least as much as noise damages. Our review of applicable measures suggests that effective policies should combine economic incentives, information campaigns, and enforcement measures, coupled with preventive environmental measures.

conference paper

How do they get by without cars in california?: Travel characteristics of voluntarily and involuntarily carless households

Proceedings of the 98th annual meeting of the transportation research board

Publication Date

January 1, 2019

Abstract

In spite of their increasing number in the U.S., our understanding of the travel behavior of households who do not own motor vehicles (labeled â??carlessâ?? herein) is sketchy. The goal of this paper is to start filling this gap for California. The authors perform parametric and non-parametric tests to analyze trip data from the 2012 California Household Travel Survey (CHTS) after classifying carless households as voluntarily carless, involuntarily carless, or unclassifiable based on a CHTS question that inquires why a carless household does not own any motor vehicle. The authors find substantial differences between voluntarily and involuntarily carless households. Compared to their voluntarily carless peers, involuntarily carless households travel less frequently, their trips are longer and they take more time, partly because their environment is not as well adapted to their needs. They also walk/bike less, depend more on transit, and when they travel by motor vehicle, occupancy is typically higher. Their median travel time is also longer, but remarkably, it is similar for voluntarily carless and motorized households. Overall, involuntarily carless households are less mobile, which may contribute to a more isolated lifestyle with a lower degree of well-being. Compared to motorized households, carless households rely a lot less on motor vehicles and much more on transit, walking, and biking. They also take less than half as many trips and their median trip distance is less than half as short. This study is a first step toward better understanding the transportation patterns of carless households.

Suggested Citation
Suman K. Mitra and Jean-Daniel M. Saphores (2019) “How do they get by without cars in california?: Travel characteristics of voluntarily and involuntarily carless households”, in Proceedings of the 98th annual meeting of the transportation research board, p. 7p.

conference paper

MitM attack by name collision: Cause analysis and vulnerability assessment in the new gTLD era

2016 IEEE symposium on security and privacy (SP)

Publication Date

May 1, 2016

Author(s)

Qi Alfred Chen, Eric Osterweil, Matthew Thomas, Z. Morley Mao
Suggested Citation
Qi Alfred Chen, Eric Osterweil, Matthew Thomas and Z. Morley Mao (2016) “MitM attack by name collision: Cause analysis and vulnerability assessment in the new gTLD era”, in 2016 IEEE symposium on security and privacy (SP). IEEE, pp. 675–690. Available at: 10.1109/sp.2016.46.

policy brief

A Review of Reduced and Free Transit Fare Programs in California

Publication Date

May 1, 2020

Policy Brief

UC-ITS-2019-55-pb

Areas of Expertise

Abstract

Free or reduced-fare transit passes have the potential to increase transit ridership, enhance the mobility of underserved groups (e.g., low-income, seniors, and youth), and reduce the environmental footprint of transportation. Under the right conditions, these programs can also help reduce traffic congestion and motor vehicle use. Transit agencies in different parts of the world have been experimenting with free or reduced-fare transit for decades, yet there are still substantial concerns about the impacts of free or reduced-fare transit on ridership as well as on the fiscal health of transit agencies. Some of these concerns linger partly because rigorous academic studies on free and reduced-fare transit passes are still rare.

Suggested Citation
Jean-Daniel Saphores (2020) A Review of Reduced and Free Transit Fare Programs in California. Policy Brief UC-ITS-2019-55-pb. UC ITS. Available at: https://doi.org/10.7922/g2fj2f4s.