Bicycle-Route Choice Model Incorporating Distance and Perceived Risk

Abstract

In recent years, concerns about traffic congestion and human health have led to programs that encourage bicycle use. To aid bicycle planners and city engineers in providing useful facilities, an understanding of bicyclists’ route choice would be helpful. This paper describes a practical procedure to estimate bicycle link cost function parameters for use in a bicycle-route choice model. A bilevel optimization problem is formulated. Based on bicycle commuters’ revealed preference choices for routes to a university campus, cost functions that used distance and perceived risk terms were tested. Model forms that used only distance or only risk were clearly inferior. Three forms that combined both distance and risk factors gave good results. An elasticity ratio test was conducted to investigate the relative importance of travel distance and risk concern. The results indicate that for the database used, travel distance is more important in route choice decisions. However, when perceived risk reaches high levels, the role of the risk factor in bicycle-route choice becomes almost as important as the distance factor. The bilevel optimization method used in this study provides a practical way to approximate bicyclist route choice behavior using a simple measure (distance) and the well-recognized Bicycle Compatibility Index. The results can guide investments in bicycle facilities.