Numerous extant studies are dedicated to enhancing the safety of active transportation modes, but very few studies are devoted to safety analysis surrounding transit stations, which serve as an important modal interface for pedestrians and bicyclists. This study bridges the gap by developing joint models based on the multivariate conditionally autoregressive (MCAR) priors with a distance-oriented neighboring weight matrix. For this purpose, transit-station-centered data in Los Angeles County were used for model development. Feature selection relying on both random forest and correlation analyses was employed, which leads to different covariate inputs to each of the two jointed models, resulting in increased model flexibility. Utilizing an Integrated Nested Laplace Approximation (INLA) algorithm and various evaluation criteria, the results demonstrate that models with a correlation effect between pedestrians and bicyclists perform much better than the models without such an effect. The joint models also aid in identifying significant covariates contributing to the safety of each of the two active transportation modes. The research results can furnish transportation professionals with additional insights to create safer access to transit and thus promote active transportation.
Dr. Yongping Zhang is an assistant professor of Transportation Engineering at California State Polytechnic University, Pomona. He is also a licensed professional engineer in Civil Engineering. During 2009–2015, Dr. Zhang worked as a Senior Transportation Modeler for the Southern California Association of Governments; before that, he worked as a Transportation Analyst at Wilbur Smith Associates in the Chicago area for two years.
Dr. Wen Cheng is a professor of Transportation Engineering at California State Polytechnic University, Pomona. His research focuses on highway safety, statistical modeling, traffic operation, and management. He received the 2015 Outstanding Research Award and the 2018 Outstanding Teaching Award from Cal Poly Pomona College of Engineering. Dr. Cheng has published numerous journal papers in the fields of traffic safety and operation, machine learning, and air quality.
Dr. Xudong Jia is a professor of Transportation Engineering and the Chair of the Civil Engineering Department at California State Polytechnic University, Pomona. He has been working in civil engineering and transportation engineering education, applied research, and consulting for more than 25 years. He has received the Outstanding Organization and Individual Achievement Awards from the National Transit Standards Consortium.