policy brief

California Travel Post-Pandemic Has Changed: Are Our Policies Keeping Up?

Publication Date

May 1, 2026

Abstract

The COVID-19 pandemic fundamentally changed how Californians travel, work, and shop. While overall travel levels have largely recovered, the rise of remote work, online shopping, and more flexible schedules have reshaped when, why, and how people travel. Yet many transportation policies and planning tools still rely on outdated assumptions about travel behavior, creating a growing mismatch between policy and reality, with implications for infrastructure planning, congestion, air pollutant emissions, and more. To better understand these changes, the research team analyzed travel data from 2019 and 2023 across four primary travel modes–driving, public transit, walking, and bicycling. To examine changes in driving and transit, the research team used data from sites around the state for driving and transit use, in addition to data from the Southern California Association of Governments (SCAG) region to analyze walking and biking.

working paper

Product Differentiation on Roads: Second-Best Congestion Pricing with Heterogeneity under Public and Private Ownership

Publication Date

June 1, 1999

Author(s)

Erik T. Verhoef, Kenneth Small

Working Paper

UCI-ITS-WP-99-1

Areas of Expertise

Abstract

We explore the properties of various types of public and private pricing on a congested road network with heterogeneous users and allowing for elastic demand. Heterogeneity is represented by a continuum of values of time. The network consists of both serial and parallel links, which allows us to model second-best pricing restrictions on either complementary or substitute links, while still accounting for interaction between different groups on shared links (e.g. in city centres). We find that private (revenue-maximizing) pricing is much less efficient than public, whether on the partial or the full network; but this difference is mitigated by the product differentiation made possible by heterogeneous users. Ignoring heterogeneity causes the welfare benefits of second-best pricing of one parallel link, a policy currently receiving favourable consideration, to be dramatically underestimated Product differentiation produces some unexpected distributional effects, including the possibility that first-best pricing can result in one of the parallel routes being both more expensive and more congested than with no pricing.

Suggested Citation
Erik T. Verhoef and Kenneth A. Small (1999) Product Differentiation on Roads: Second-Best Congestion Pricing with Heterogeneity under Public and Private Ownership. Working Paper UCI-ITS-WP-99-1. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/8h45v1v3.

working paper

Estimation of Vehicular Emissions by Capturing Traffic Variations

Abstract

Increase in traffic volumes and changes in travel-related characteristics increase vehicular emissions significantly. It is difficult, however, to accurately estimate emissions with current practice because of the reliance on travel forecasting models that are based on steady state hourly averages and, thus, are incapable of capturing the effects of traffic variations in the transportation network. This paper proposes an intermediate model component that can provide better estimates of link speeds by considering a set of Emission Specific Characteristics (ESC) for each link. The intermediate model is developed using multiple linear regression; it is then calibrated, validated, and evaluated using a microscopic traffic simulation model. The improved link speed data can then be used to provide better estimates of emissions. The evaluation results show that the proposed emission estimation method performs better than current practice and is capable of estimating time-dependent emissions if traffic sensor data are available as model input.

Suggested Citation
K.S. Nesamani, Lianyu Chu, Michael G. McNally and R. Jayakrishnan (2005) Estimation of Vehicular Emissions by Capturing Traffic Variations. Working Paper UCI-ITS-WP-05-6. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/7gz0f9sf.

published journal article

Inventory planning with forecast updates: Approximate solutions and cost error bounds

Operations Research

Publication Date

December 1, 2006
Suggested Citation
Xiangwen Lu, Jing-Sheng Song and Amelia Regan (2006) “Inventory planning with forecast updates: Approximate solutions and cost error bounds”, Operations Research, 54(6), pp. 1079–1097. Available at: 10.1287/opre.1060.0338.

conference paper

A new formulation for the traveling salesman problem with separation requirement and cost

Proceedings of the 90th annual meeting of the transportation research board, washington, DC

Publication Date

January 1, 2011
Suggested Citation
X. Wang and A.C. Regan (2011) “A new formulation for the traveling salesman problem with separation requirement and cost”, in Proceedings of the 90th annual meeting of the transportation research board, washington, DC.

conference paper

High coverage point-to-point transit: Local vehicle routing problem with genetic algorithms

2011 14th international IEEE conference on intelligent transportation systems (ITSC)

Publication Date

October 1, 2011

Author(s)

Suggested Citation
Jaeyoung Jung, R. Jayakrishnan and Doohee Nam (2011) “High coverage point-to-point transit: Local vehicle routing problem with genetic algorithms”, in 2011 14th international IEEE conference on intelligent transportation systems (ITSC). IEEE. Available at: 10.1109/itsc.2011.6082818.

published journal article

Performance Based Funding Allocation guidelines for Transit Operations in Los Angeles County

Transportation Research Record

Publication Date

January 1, 1982

Author(s)

Gordon (Pete) Fielding, Subhash R Mundle, Joe Misner

Abstract

During the last five years, transit performance indicators have been widely used in the transit industry. California and New York have used performance indicators to determine eligibility for funding. In Pennsylvania, transit performance measures have been used to provide incentive payments for superior performance, and in Michigan a detailed analysis of transit operations provides the basis for state managerial assistance. In Los Angeles County, nine transit operators, including Southern California Rapid Transit District, provide fixedroute transit service. Between 1977 and 1980, operating cost per vehicle hour increased from $28.52 to $38.76, a rate higher than the consumer price index for the Los Angeles area. In response to state legislation designed to maximize utilization of public subsidies for transit, the Los Angeles County Transportation Commission undertook the development of performance-based guidelines for allocating transit subsidies. The performance guidelines developed in cooperation with the local transit operators are presented here. In this program, service is classified into local and express categories. Seven indicators were chosen to monitor transit performance on a periodic basis. Three indicators were selected to establish standards to be achieved by all fixed-route service operators in Los Angeles County. Compliance with these standards will determine eligibility for discretionary funds (representing 5 percent of operating assistance) in the future. The methodology for quantifying loss of subsidy funds if an operator falls below the established standards is also described. The performance guidelines merit consideration for two reasons. First, they represent an attempt by a large metropolitan area to control transit costs, and second they initiate performance-based funding allocation rather than funding based on demographic characteristics or operating deficits. Both reasons are substantial advancements in the theory and application of performance-based guidelines to transit-financing issues.

Suggested Citation
Gordon J Fielding, Subhash R Mundle and Joe Misner (1982) “Performance Based Funding Allocation guidelines for Transit Operations in Los Angeles County”, Transportation Research Record, (857), pp. 14--18. Available at: https://onlinepubs.trb.org/Onlinepubs/trr/1982/857/857-003.pdf.

conference paper

Towards Driving-Oriented Metric for Lane Detection Models

Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition

Publication Date

January 1, 2022
Suggested Citation
Takami Sato and Qi Alfred Chen (2022) “Towards Driving-Oriented Metric for Lane Detection Models”. Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pp. 17153–17162. Available at: https://openaccess.thecvf.com/content/CVPR2022/html/Sato_Towards_Driving-Oriented_Metric_for_Lane_Detection_Models_CVPR_2022_paper.html (Accessed: October 5, 2023).

published journal article

Assessing the role of geographic context in transportation mode detection from GPS data

Journal of transport geography

Publication Date

January 1, 2022

Author(s)

Avipsa Roy, Daniel Fuller, Trisalyn Nelson, Peter Kedron
Suggested Citation
Avipsa Roy, Daniel Fuller, Trisalyn Nelson and Peter Kedron (2022) “Assessing the role of geographic context in transportation mode detection from GPS data”, Journal of transport geography, 100, p. 103330. Available at: 10.1016/j.jtrangeo.2022.103330.

published journal article

Growth controls and land values in an open city

Land Economics

Publication Date

August 1, 1990

Author(s)

Suggested Citation
Jan K. Brueckner (1990) “Growth controls and land values in an open city”, Land Economics, 66(3), p. 237. Available at: 10.2307/3146726.