A New Model for the Estimation of Waiting Time at Public Transport Stops

Abstract

This article presents the development of a new model for estimating the average waiting time for passengers who arrive at a single public transport stop and must wait until a vehicle with sufficient capacity to board passes by. Most currently existing models consider that this time depends only on the average residual capacity of the vehicles and the average passenger flow at the stop under study. However, our theoretical and simulated results demonstrate that average waiting time is strongly affected by other flows in the network and that average residual capacity models can considerably underestimate its value. This analysis examines how the variability of available seats on buses affects average waiting times and presents a model that incorporates this effect. Unlike residual capacity models, which perform well only at low congestion levels, this new model is more robust, in the sense that its performance is very good for low and medium congestion levels. A comparison with other existing models shows that at medium congestion levels (50% network utilization), the latter estimate the average waiting time with average errors exceeding 40%, while the average error of the proposed model is less than 6%. From a computational point of view, the new model is easy to implement in passenger assignment programs — which allow for the study of public transport network usage — because it corresponds to a closed formula for direct evaluation with information that is generally available in such programs or easy to obtain.