Perception-Based Walkability Index to Test Impact of Micro level Walkability on Sustainable Mode Choice Decisions

This pilot study had two major research goals. The first goal was to develop a perception-based composite walkability index, with which researchers could evaluate the microlevel quality of the walking environment in an objective and systematic way. The second goal was to test the impact of microlevel walkability on mode choices, including walking as a travel option. For the development of a perception-based composite walkability index, a case study was conducted in the station area near the downtown of Mountain View, California, in the San Francisco Bay Area. Three surveys were conducted: a walker perception survey, a station user survey, and a street survey measuring microlevel walkability. A series of regression models was performed with the perception scores from surveyed transit users on the basis of their access trips to the station and with the objective microlevel walkability measured from their routes. The final outcome was a new formula for a composite walkability index. On the basis of the results of the station user survey, a pair of mode choice models was estimated to find the probability of transit users choosing walking over automobiles for their access trips to the station. The study introduced the new walkability index as a new walkability variable, which successfully entered the extended model and showed that it could improve the model in a statistically significant way.