Open AccessStochastic effects of traffic randomness on the determination of signal change and clearance intervals at signalised intersections
Author(s) -
Wang Fen,
Tang Keshuang,
Li Keping
Publication year - 2015
Publication title -
iet intelligent transport systems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.579
H-Index - 45
eISSN - 1751-9578
pISSN - 1751-956X
DOI - 10.1049/iet-its.2013.0186
Subject(s) - randomness , reliability (semiconductor) , intersection (aeronautics) , computer science , probabilistic logic , logit , sensitivity (control systems) , traffic flow (computer networking) , reliability engineering , engineering , statistics , mathematics , transport engineering , machine learning , artificial intelligence , quantum mechanics , electronic engineering , power (physics) , physics , computer security
Conventional methods of intergreen time design are based on deterministic traffic flow theory and are difficult to fully reflect traffic randomness especially driver's decision differences. This study is to develop a probabilistic model to extensively investigate the effects of traffic flow randomness and driver's decision errors on the determination of intergreen times. An analytical framework was proposed based on a safety reliability model earlier developed by the authors and validated based on field data at a typical high‐speed intersection in Shanghai. Then, comprehensive sensitivity analysis was performed to look into the fluctuation of safety reliability towards critical variables as well as their variations and correlations. Two logistic regression models were developed to quantify the effects of each random component on the probabilities of risky behaviour and clearance failure, that is, safety reliability indicators for intergreen intervals. To facilitate easy applications of the proposed approach, a set of scenario analysis were done to calculate the required intergreen intervals under different traffic conditions and safety reliability levels. Application tables were finally provided for signal design, which are able to recommend more sophisticated intergreen times and thus aid the practitioners to select proper intergreen times according to local conditions without complicated calculation.