TTI-01-04 Final Research Report: Influences on Bicyclists and Motor Vehicles Operating Speed within a Corridor1390 DownloadsAbstract This research explored (1) the relationship between suburban vehicle operating speed and roadway characteristics, especially the presence of bicyclists and (2) whether crowdsourced speed data could be used to estimate the unconstrained speed for a location. Both vehicle volume per lane and bicycle volume were found to be influential in affecting average speed on lower speed urban arterial roadways. For 40.3 km/hr (25 mph) sites, an increase of 19 vehicles per 15-min period would decrease average speed by 1.6 km/hr (1 mph), and an … TTI-01-04 Final Research Report: Influences on Bicyclists and Motor Vehicles Operating Speed within a Corridor
02-027 Final Research Report: Street Noise Relationship to Bicycling Road User Safety1310 DownloadsAbstract Vulnerable road users, such as bicyclists, experience road noise directly. This study explored the relationship between bicycle crash risk and street-level road noise as measured in Austin, Texas and the Washington, D.C. metropolitan area, in addition to other factors. Construction and validation of a method to measure noise directly using consumer-accessible tools supports additional studies as well as potential public crowdsourcing applications for urban planning. Results from the two case sites were mixed. Street noise, as measured on our chosen routes, was not a consistent predictor of … 02-027 Final Research Report: Street Noise Relationship to Bicycling Road User Safety
02-026 Final Research Report: Sources and Mitigation of Bias in Big Data for Transportation Safety1256 DownloadsAbstract Emerging big data resources and practices provide opportunities to improve transportation safety planning and outcomes. However, researchers and practitioners recognize that big data includes biases in who the data represents and accuracy related to transportation safety statistics. This study systematically reviews both the sources of bias and approaches to mitigate bias through review of published studies and interviews with experts. The study includes quantified analysis of topic frequency and evaluation of the reliability of concepts by using two independent trained coders. Results show a … 02-026 Final Research Report: Sources and Mitigation of Bias in Big Data for Transportation Safety