Modelling travellers’ route choice behaviours with the concept of equivalent impedance

A novel concept is presented to capture route choice behaviours and to account for the correlation of routes in the logit model. The issue that route choice models are easily affected when irrelevant alternatives are included in the choice set is tackled. The concept of equivalent impedance is presented to simplify and aggregate a set of links based on the idea that people tend to remember and process road network information at an abstract level. Then, the equivalent impedance is utilized to derive a correction term for the utility of a multinomial logit model in which the advantages of a closed-form structure and easy computation remain unchanged. The results from the numerical examples suggest that the proposed model obtains reasonable results and provides more stable predictions than comparable models when the composition of the choice set changes. An application in a real urban network with GPS data is presented, and estimation results suggest that the new model is practical due to its robustness.