Assessing the Spatial Transferability of the Pedestrian Index of the Environment (PIE)

The urban structure and the built environment have been found to exert a determining impact on active transportation behavior. However, a lot of the variables related to the urban structure are strongly correlated when measured at the neighborhood or trip level. Composite walkability measures, which combine several of these neighborhood variables into a single score, are increasingly popular solutions to circumvent the problem. This paper uses trip data from the 2013 Origin-Destination survey to analyze the transferability of a composite walkability measure, the Pedestrian Index of the Environment (PIE), to the Greater Montréal Area (GMA). Developed in Portland, Oregon, the PIE is a grid-based measure combining six neighborhood variables into a score ranging from 20 to 100. Mode choice models are estimated on different subsets of short trips to study the impact of the PIE on predicting walking behavior. Significant correlation is found between the PIE and the choice of walking for short trips, for all purposes. The inclusion of the PIE also improves the accuracy of the modelling process. The PIE can therefore be used in the GMA, and potentially in other metropolitan areas, to explain active travel behavior for short trips and help researchers and practitioners to better understand the effect of the urban form on walk trips