Data

Collaboration Math: Enhancing the Effectiveness of Multidisciplinary Collaboration

Cohen, Larry
Aboeleta, Manal
Gantz, Toni
Van Wert, Jennifer
2003

Reducing the toll of traffic-related injuries requires a concerted effort, calling on the resources, commitment and expertise of diverse agencies, professionals and community members. Traffic safety is affected by numerous aspects of community life such as how neighborhoods are designed, how fast cars travel and how safe people feel walking or driving to key destinations. Preventing traffic-related injury is a responsibility shared by many. As evidenced by many federal, state and local efforts, partnerships, coalitions and networks have become common ways to address the incidence of...

Pilot Models for Estimating Bicycle Intersection Volumes

Griswold, Julia B.
Medury, Aditya
Schneider, Robert J.
2011

Bicycle volume data are useful to practitioners and researchers to understand safety, travel behavior, and development impacts. This paper describes the methodology used to develop several simple models of bicycle intersection volumes in Alameda County, California. The models are based on two-hour bicycle counts performed at a sample of 81 intersections in the Spring of 2008 and 2009. Study sites represented areas with a wide range of population density, employment density, proximity to commercial property, neighborhood income, and street network characteristics. The explanatory variables...

Automated Assessment of Safety-Critical Dynamics in Multi-modal Transportation Systems

Medury, Aditya
Yu, Mengqiao
Bourdais, Cedric
Grembek, Offer
2016

With the advent of emerging technologies, urban intersections are being increasingly equipped with various types of video-based and in-pavement sensing systems to facilitate round-the-clock monitoring and optimization of multi-modal flows. In comparison, the assessment of the safety performance of these facilities continues to be largely based on either crash history or citizen grievances. Herein lies an opportunity to apply advanced sensing platforms to proactively monitor safety-critical events of multi-modal road users. This work presents a traffic safety monitoring framework which...

Effectiveness of a Commercially Available Automated Pedestrian Counting Device in Urban Environments: Comparison with Manual Counts

Greene-Roesel, Ryan
Diogenes, Mara Chagas
Ragland, David R.
Lindau, Luis Antonio
2008

High-quality continuous counts of pedestrian volume are necessary to evaluate the effects of pedestrian infrastructure investments and to improve pedestrian volume modeling. Automated pedestrian counting devices can meet the need for continuous counts of pedestrian volume and reduce the labor cost associated with manual pedestrian counting and data entry. However, most existing automated pedestrian devices are not well suited to the task of counting pedestrians in outdoor environments, and little is known about their effectiveness and accuracy. This study addresses the lack of performance...

Frank Proulx, NCHRP 07-19: Methods and Technologies for Pedestrian and Bicycle Volume Data Collection

Proulx, Frank
2014

In this talk, an overview of the recently completed National Cooperative Highways Research Program project 07-19 will be presented. In NCHRP 07-19, research was conducted on a variety of methods and technologies for collecting bicyclist and pedestrian volume data. Research included a practitioner's survey, in-depth interviews with count program managers, and field testing and accuracy evaluation of six counting technologies. Counters were installed at roughly 15 different sites and evaluated for precision and reliability. The main product of this project is a guidebook on conducting counts...

Methods and Technologies for Pedestrian and Bicycle Volume Data Collection

Proulx, Frank
2014

In this talk, an overview of the recently completed National Cooperative Highways Research Program project 07-19 will be presented. In NCHRP 07-19, research was conducted on a variety of methods and technologies for collecting bicyclist and pedestrian volume data. Research included a practitioner's survey, in-depth interviews with count program managers, and field testing and accuracy evaluation of six counting technologies. Counters were installed at roughly 15 different sites and evaluated for precision and reliability. The main product of this project is a guidebook on conducting counts...

Impact of Traffic States on Freeway Collision Frequency

Yeo, Hwasoon
Jang, Kitae
Skabardonis, Alexander
2010

Freeway collisions are thought to be affected by traffic states. To reduce the number of collisions, the study to reveal how the traffic states influence collisions are required. Therefore, the purpose of the paper is to suggest a method to relate traffic states to collision frequency in freeway. We first defined section- based traffic phases showing traffic state of a section using upstream and downstream traffic states: free flow (FF), back of queue (BQ), bottleneck front (BN) and congestion (CT). Secondly, by integrating freeway collision data and traffic data from the California PeMS...

California Traffic Safety Survey 2024: Data Analysis and Comparison with 2010-2023 Survey Data Results

Ewald & Wasserman Research
2024

The 2024 California Traffic Safety Public Opinion Study was conducted on behalf of the California Office of Traffic Safety (OTS) and the Safe Transportation Research and Education Center of UC Berkeley (SafeTREC), using an online self-administered survey. Similar to previous years of the study, the survey panelists were provided through Marketing Services Group, a commercial sample and panel vendor. To ensure a comparable sample disposition to previous years of data collection, six quota groups were set for age and gender groups based on the California census and previous waves of the...

Observational Study of Cell Phone and Texting Use Among California Drivers 2012 and Comparison to 2011 Data

Cooper, Jill F
Ragland, David R
Ewald, Katrin
Wasserman, Lisa
Murphy, Christopher J
2013

This methodological report describes survey research and data collection methods employed for the second Observational Survey of Cell Phone and Texting Use among California Drivers study conducted in 2012. This study was conducted by Ewald & Wasserman Research Consultants (E&W) on behalf of the California Office of Traffic Safety and the Safe Transportation Research and Education Center at University of California at Berkeley. The survey’s goal was to obtain a statewide statistically representative observational sample of California’s cell phone use behaviors, focusing on...

High Collision Concentration Location: Table C Evaluation and Recommendations

Ragland, David R.
Chan, Ching-Yao
2007

This report describes the research work that was conducted under PATH Task Order 5215 and its extension Task Order 6215, “Methods for Identifying High-Concentration Collision Locations (HCCL).” The subject matter is related to regularly published Caltrans reports, so-called Table C, that are used to screen for and investigate locations within the California State Highway System that have collision frequencies significantly greater than the base or expected numbers when compared to other locations. The accuracy and reliability of such reports are critical as Table C is the basis for follow-...