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C H A P T E R 1 Introduction SHRP 2 was established in 2006 to investigate the under- investigation of the relationship between observable driver lying causes of highway crashes and congestion in a short-term behavior and nonrecurring congestion to improve travel time program of four interrelated focus areas: Safety (significantly reliability. The successful execution of this research effort improve highway safety by understanding driving behavior requires an in-depth understanding of existing research using in a study of unprecedented scale); Renewal (develop design video camera data and research about the modeling of travel and construction methods that cause minimal disruption time reliability. and produce long-lived facilities to renew the aging high- The team investigated key domestic and international way infrastructure); Reliability (reduce congestion and improve studies that used in-vehicle video cameras to collect data. travel time reliability through incident management, response, After an initial screening of candidate data sets, the feasibil- and mitigation); and Capacity (integrate mobility, economic, ity of using existing data was assessed by assigning scores environmental, and community needs into the planning to five general areas: access to the data; comprehensiveness and design of new transportation capacity). This report of the data; types of vehicle performance data collected; results from Project L10, part of the Reliability research of ability to link to operational, traffic control, work zone, and SHRP 2. environmental data; and data structure and format. The Nonrecurring congestion is traffic congestion that results evaluation results generated a list of potential data sets. The from nonrecurring causes, such as crashes, disabled vehicles, data sets were examined in further detail, determining cri- work zones, adverse weather events, and planned special events. teria to identify crashes and near crashes, contributing fac- According to data from the Federal Highway Administration tors to these safety-related events, and countermeasures to (FHWA), approximately half of all congestion is caused by prevent these events. The team then reviewed literature in temporary disruptions that remove part of the roadway from both the traffic engineering and human factors arena on use, or nonrecurring congestion. These nonrecurring events safety impacts of driver behavior and travel time reliability. dramatically reduce the available capacity and reliability of A new statistical method was also developed to model travel the entire transportation system. Three main causes of non- time reliability. recurring congestion are incidents ranging from a flat tire to To provide constructive suggestions for the next stage of an overturned hazardous material truck (25% of congestion), research, potential problems and risks were identified and work zones (10% of congestion), and weather (15% of con- reviewed to determine strategies to address these shortcom- gestion). Accidents resulting in fatalities and injuries may ings. Issues worthy of notice for future data collection efforts occur if a driver behaves in an inappropriate or less-than- and the general guidelines for video data reduction and analy- optimal manner in response to such factors as incident scenes, sis are also discussed. work zones, inclement weather, roadside distractions, and The current report conveys the results of this effort, queues of vehicles. beginning with an introduction of the existing video-based In-vehicle video, along with other data, can potentially driver performance databases (Tasks 1 and 2, as described provide insight regarding how to modify driver behavior that in Chapter 2). Chapter 3 details each data set and identifies contributes to nonrecurring congestion. The objective of this qualified data sources by assigning scores to the data set, project is to determine the feasibility of using in-vehicle video including comprehensiveness, types of data, and data structure data to make inferences about driver behavior that would allow (Tasks 2 and 3). Chapter 4 details issues about data storage and 6