Journal
TRANSPORTATION RESEARCH PART B-METHODOLOGICAL
Volume 157, Issue -, Pages 175-202Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.trb.2022.02.001
Keywords
Transit network; Transit equilibrium assignment model; Sensitivity analysis; Uncertainty analysis; Analytical approach
Categories
Funding
- Natural Science Foundation of China [71801079]
- Research Grants Council of the Hong Kong Special Administrative Region [15267117]
- Research Committee of the Hong Kong Polytechnic Uni-versity [1-ZVJV]
- Research Institute for Sustainable Urban Development at the Hong Kong Polytechnic University [1-BBWF, 72071174]
- Natural Science Foundation of China at the Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, Guangdong, China
Ask authors/readers for more resources
Systematic uncertainty analysis is crucial for evaluating the variation in model outputs and identifying critical sources of uncertainty to enhance the reliability and stability of a system. This study presents a sensitivity-based uncertainty analysis approach in equilibrium transit systems, considering uncertainties caused by probabilistic travel demand, congestion, and vehicle frequencies. The proposed method incorporates the congestion effect in passengers' route-choice models and utilizes the hyperpath concept to handle the common-line problem at transit stops. The developed approach enables the simultaneous propagation of uncertainties from different input sources to the model outputs, contributing to the practical applications of sensitivity and uncertainty analyses.
Systematic uncertainty analysis can be used to quantitatively evaluate variation in model outputs and identify the critical sources of uncertainty to improve the reliability and stability of a system. To analyze the effects of uncertainties in transit networks that may be caused by probabilistic travel demand, congestion, or vehicle frequencies, this study develops a sensitivity-based uncertainty analysis approach as a post-analysis tool for equilibrium transit systems. The congestion effect is considered in the waiting time and in-vehicle travel time of a passengers' route-choice model. The hyperpath concept is used to manage passengers' riding strategies due to the common-line problem at transit stops. A hyperpath-based gradient projection (GP) solution algorithm is developed for the solution of the variational inequality formulation of the transit equilibrium assignment problem (TEAP). A restricted sensitivity analysis approach originally developed for road networks is re-developed for the TEAP in transit networks. An analytical sensitivity-based approach is derived to conduct uncertainty analysis for the TEAP, which enables the simultaneous propagation of uncertainties from different input sources to the model outputs. Numerical examples are provided for the following purposes. (1) To demonstrate three applications of the sensitivity analysis of the TEAP, namely the perturbed solution estimation problem, the critical parameter identification problem, and the paradox analysis problem. (2) To illustrate the use of uncertainty analysis of the TEAP, such as estimating the variance and confidence level of model outputs with respect to various model inputs/parameters as random variables, and ranking the importance of arcs using sensitivity-based uncertainty analysis. (3) To demonstrate the applicability of the proposed approach to real transit networks. The findings demonstrate not only the importance of the analytical sensitivity analysis development for the TEAP, but also for the practical applications of sensitivity and uncertainty analyses.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available