title: Analysis of vehicle-bicycle interactions at unsignalized crossings: A probabilistic approach and application.
abstract: In the last decades, bicycle usage has been increasing in many countries due to the potential environmental and health benefits. Therefore, there is a need to better understand cyclists' interactions with vehicles, and to build models and tools for evaluating multimodal transportation infrastructure with respect to cycling safety, accessibility, and other planning aspects. This paper presents a modeling framework to describe driver-cyclist interactions when they are approaching a conflicting zone. In particular, the car driver yielding behavior is modeled as a function of a number of explanatory variables. A two-level hierarchical, probabilistic framework (based on discrete choice theory) is proposed to capture the driver's yielding decision process when interacting with a cyclist. The first level models the probability of the car driver perceiving a situation with a bicycle as a potential conflict whereas the second models the probability of yielding given that a conflict has been perceived by the driver. The framework also incorporates the randomness of the location of the drivers' decision point. The methodology is applied in a case study using observations at a typical Swedish roundabout. The results show that the conflict probability is affected differently depending on the user (cyclist or driver) who arrives at the interaction zone first. The yielding probability depends on the speed of the vehicle and the proximity of the cyclist.
authors: Department of Transport Science, Division of Transport Planning, Economics and Engineering, KTH Royal Institute of Technology, Teknikringen 72, Stockholm 10044, Sweden. Electronic address: aryps@kth.se.
authors: Ary P
authors: AP
authors: Silvano
authors: Department of Transport Science, Division of Transport Planning, Economics and Engineering, KTH Royal Institute of Technology, Teknikringen 72, Stockholm 10044, Sweden; Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, United States.
authors: Haris N
authors: HN
authors: Koutsopoulos
authors: Department of Transport Science, Division of Transport Planning, Economics and Engineering, KTH Royal Institute of Technology, Teknikringen 72, Stockholm 10044, Sweden.
authors: Xiaoliang
authors: X
authors: Ma
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control* / Q000523:psychology; D000374:Aggression; D001334:Automobile Driving / Q000523:psychology / Q000706:statistics & numerical data*; D001642:Bicycling / Q000523:psychology / Q000706:statistics & numerical data*; D003654:Deceleration; D004779:Environment Design; D006801:Humans; D008962:Models, Theoretical; D011336:Probability; D018570:Risk Assessment; D012449:Safety / Q000706:statistics & numerical data
keywords: Cyclist safety; Logit model; Maximum likelihood estimation; Roundabout; Unsignalized intersection; Vehicle-bicycle interaction; Yielding behavior