conference paper

Behavioral model for Ingress/Egress decision on buffer-separated HOV facilities for microsimulation model

Proceedings of the 89th annual meeting of the transportation research board

Publication Date

January 1, 2010

Abstract

High-Occupancy Vehicle (HOV) lanes, commonly known as carpool lanes, have been accepted as a cost-effective and environmental-friendly alternative in many metropolitan areas. It is thus very important to find ways to evaluate HOV strategies during the decision making process, and prior to any implementation. An alternative approach is microscopic traffic simulation. However, current micro-simulation models have limited capabilities to model HOV driver behaviors, particularly with respect to buffer-separated facilities. This study proposed a probabilistic HOV driver behavioral model based on discrete choice modeling derived from random utility principles, which includes a preferred access choice model for examining travel time savings and a traffic model for calculating the acceptable gap to get in/out the HOV lane. A HOV access plugin was also developed using a micro-simulation tool, Paramics, based on the proposed model. Its theoretical capability is extended to real-world application via providing additional â??implementationâ?? parameters, such as ingress and egress points selection control, and update frequency of traffic information. A real-world freeway network, SR-57 in Orange County, California, was selected to analyze the reasonableness of the model through sensitivity analysis, and was further investigated for model validation purposes. The results have shown the reasonableness of the proposed model under various traffic conditions. The proposed model also demonstrated its feasibility and applicability via setting various calibration parameters and control parameters.

Suggested Citation
Shin-Ting (Cindy) Jeng, Will Recker and Lianyu Chu (2010) “Behavioral model for Ingress/Egress decision on buffer-separated HOV facilities for microsimulation model”, in Proceedings of the 89th annual meeting of the transportation research board, p. 32p.

research report

Exploring Transportation Mode Choice and Participation in LA Metro’s “GoPass” Program Among Los Angeles Community College Students

Publication Date

July 2, 2026

Research Report

UC-ITS-2024-32

Abstract

This research evaluates LA Metro’s GoPass program—a fare-free transit initiative for K-12 and community college students—through a survey of Los Angeles Community College District (LACCD) students. The research team investigated students’ travel preferences through a discrete choice experiment, assessed GoPass awareness and participation impacts on transit use, and analyzed spatial and seasonal ridership patterns from TAP card records. GoPass participation increased transit use by 26 percentage points for school trips and 19 percentage points for discretionary trips, with greater benefits for socioeconomically disadvantaged students. Even students aware of GoPass but not participating showed a 5.8 percentage point increase in school related transit use. However, 39% of eligible students were unaware of the program, and car access reduced transit use probability by 37 percentage points. The discrete choice experiment revealed students valued travel time savings at $27–$54 per hour and Wi-Fi availability at $6–$7 per trip. Modest travel time reductions generated larger welfare gains than free fares alone, suggesting service improvements may offer better returns than fare subsidies. Analysis of 1.1 million TAP card records showed substantial seasonal variation: summer ridership declined 37.5% for buses and 32.2% for rail. Single-vehicle households maintained more consistent usage (+11.9%), while three-vehicle households showed the largest declines (-40.9%). Areas with high transit stop density and high violent crime maintained more consistent usage, reflecting transit-dependent populations. These findings demonstrate that increasing student transit ridership requires addressing service quality, coverage, and program awareness beyond fare reductions alone.

Suggested Citation
Farzana Khatun, Henry Bernal and David Brownstone (2026) Exploring Transportation Mode Choice and Participation in LA Metro’s “GoPass” Program Among Los Angeles Community College Students. Research Report UC-ITS-2024-32. UC ITS. Available at: https://doi.org/10.7922/g23b5xjx.

published journal article

Travel Probability Fields and Urban Spatial Structure: 1. Theory

Environment and Planning A: Economy and Space

Publication Date

May 1, 1983

Author(s)

M J Beckmann, Thomas Golob, Y Zahavi

Abstract

The proposed model attempts to explain how particular spatial distributions of trip destinations might arise as manifestations of the accessibility benefits and travel costs associated with a housing location. The trip distributions are elliptical, being expressed as bivariate normal distributions. The parameters of these distributions are shown to be related to the parameters of an assumed density function for activity sites (such as jobs and shops) and to travel speeds. The model implies a housing density function in a monocentric urban area which is negative exponential.

Suggested Citation
M J Beckmann, T F Golob and Y Zahavi (1983) “Travel Probability Fields and Urban Spatial Structure: 1. Theory”, Environment and Planning A: Economy and Space, 15(5), pp. 593–606. Available at: 10.1068/a150593.

published journal article

The association between ambient air pollutants and pancreatic cancer in the Multiethnic Cohort Study

Environmental Research

Publication Date

November 1, 2021

Author(s)

David Bogumil, Anna H. Wu, Daniel Stram, Juan Yang, Chiu-Chen Tseng, Loïc Le Marchand, Jun Wu, Iona Cheng, Veronica Wendy Setiawan

Abstract

Background Prior studies examining the association between ambient air pollutants and pancreatic cancer have been conducted in racially/ethnically homogeneous samples and have produced mixed results, with some studies supporting evidence of an association with fine particulate matter. Methods To further investigate these findings, we estimated exposure levels of particulate matter (PM2.5, PM10) and oxides of nitrogen (NOX, and NO2) using kriging interpolation for 100,527 men and women from the Multiethnic Cohort Study, residing largely in Los Angeles County from 1993 through 2013. We measured the association between these air pollutants and incident pancreatic cancer using Cox proportional hazards models with time-varying pollutant measures, with adjustment for confounding factors. Results A total of 821 incident pancreatic cancer and 1,660,488 person-years accumulated over the study period, with an average follow-up time of over 16 years. PM2.5 (per 10 μg/m3) was associated with incident pancreatic cancer (hazard ratio [HR] = 1.61; 95% CI, 1.09, 2.37). This PM2.5 -association was strongest among Latinos (HR = 3.59; 95% CI, 1.60, 8.06) and ever smokers (HR = 1.76; 95% CI, 1.05, 2.94). There was no association for PM10 (HR = 1.12; 95% CI, 0.94, 1.32, per 10 μg/m3), NOx (HR = 1.14; 95% CI, 0.88, 1.48, per 50 ppb), or NO2 (HR = 1.14; 95% CI, 0.85, 1.54, per 20 ppb). Conclusions Our findings support prior research identifying an association between fine particulate matter, PM2.5, and pancreatic cancer. Although not statistically heterogeneous, this association was most notable among Latinos and smokers. Future studies are needed to replicate these results in an urban setting and in a racially/ethnically diverse population.

Suggested Citation
David Bogumil, Anna H. Wu, Daniel Stram, Juan Yang, Chiu-Chen Tseng, Loïc Le Marchand, Jun Wu, Iona Cheng and Veronica Wendy Setiawan (2021) “The association between ambient air pollutants and pancreatic cancer in the Multiethnic Cohort Study”, Environmental Research, 202, p. 111608. Available at: 10.1016/j.envres.2021.111608.

published journal article

Thinking styles affect reactions to brand crisis apologies

European Journal of Marketing

Publication Date

July 1, 2016

Author(s)

Liangyan Wang, Shijian Wang, Robin Keller, Jie Li
Suggested Citation
Liangyan Wang, Shijian Wang, L. Robin Keller and Jie Li (2016) “Thinking styles affect reactions to brand crisis apologies”, European Journal of Marketing, 50(7/8), pp. 1263–1289. Available at: 10.1108/ejm-07-2014-0457.

book/book chapter

Urban Decline and the Future of American Cities:

Publication Date

January 1, 2011

Author(s)

Katharine L Bradbury, Anthony Downs, Kenneth Small

Abstract

During the past two decades, most large American cities have lost population, yet some have continued to grow. Does this trend foreshadow the death” of our largest cities? Or is urban decline a temporary phenomenon likely to be reversed by high energy costs? This ambitious book tackles these questions by analyzing the nature and extent of urban decline and growth of large U.S. cities. It includes and integrates five substudies. The first examines urban decline and some of its long-run causes, and whether cities that are losing population are performing their economic and social functions less effectively. The second substudy is a multivariate analysis of factors associated with the growth and decline of 121 large U.S. cities and their metropolitan areas. Although its causes vary, urban decline appears closely related to processes that have both upgraded individual households and generated serious problems for city governments and poor neighborhoods. A third substudy shows that neighborhood decline is part of a systematic process related to the influx of poor households into metropolitan areas. Another substudy simulates five antidecline strategies in a single metropolitan area, that of Cleveland, Ohio, and finds that severe decline (occurring in about one-fourth of large U.S. cities) could be slowed, though not stopped by vigorous policies. From the last substudy it emerges that, even if gasoline prices rose to over $2 a gallon, resulting adjustments by commuters and firms would produce little net centralization of future urban developmentthough many older neighborhoods would probably be rehabilitated. The book concludes that further losses of population and jobs in most severely declining cities are unavoidable in the near future. Even Southern and Western cities, now growing fast, will find their rate of growth slowing as further annexation of surrounding territory is limited. The book ends with two chapters discussing policies designed both to help declining population and job losses and to minimize such loses in other cities.

Suggested Citation
Katharine L Bradbury, Anthony Downs and Kenneth A. Small (2011) Urban Decline and the Future of American Cities:. Rowman & Littlefield Publishers. Available at: 10.5771/9780815719601.

research report

CCIT working paper

Publication Date

September 1, 2005

Author(s)

Lianyu Chu, Hamed Benouar, Will Recker

Abstract

This report describes a comprehensive evaluation study of an Automated Workzone Information System (AWIS) known as the Computerized Highway Information Processing System (CHIPS). The system is designed to use traffic sensors to detect traffic congestion in the work zone area. The system then delivers appropriate messages, using portable message signs, to motorists as they approach or pass through a work zone. CHIPS was deployed at a California Department of Transportation (Caltrans) work zone site near Los Angeles. The effectiveness of the system was evaluated based on three criteria: safety, diversion, and response from travelers.

Suggested Citation
Lianyu Chu, Hamed Benouar and Wilfred W. Recker (2005) CCIT working paper. University of California, Berkeley, p. 67p.

published journal article

Do employment centers matter? Consequences for commuting distance in the Los Angeles region, 2002–2019

Cities

Publication Date

February 1, 2024

Author(s)

Jaehyun Ha, Sugie Lee, Jae Hong Kim, John R. Hipp

Abstract

The presence of employment centers provides the potential for reducing commuting distance. However, employment centers have distinct attributes, which may lead to varied impacts on commuting outcomes. We examine how proximity to employment centers can influence commuting distance with consideration of the heterogeneity of employment centers and workers. Specifically, we consider various attributes of employment centers related to location, persistency, job density, industry diversity, and size and analyze their impacts on the commuting patterns of low- and high-income workers using panel (2002-2019) data. Our analysis of the Los Angeles region shows that increasing proximity to the nearest employment center decreases commuting distance even after controlling for the job attributes located in the neighborhood of workers. The results further suggest that employment centers are not equal in terms of their impact on commute distance and that their impact is different for commuters from different income groups. Our findings contribute to the literature by deciphering the location and attributes of employment centers that may exert a greater impact on commuting patterns.

Suggested Citation
Jaehyun Ha, Sugie Lee, Jae Hong Kim and John R. Hipp (2024) “Do employment centers matter? Consequences for commuting distance in the Los Angeles region, 2002–2019”, Cities, 145, p. 104669. Available at: 10.1016/j.cities.2023.104669.