Does the compact city promote the pedestrian safety?

Abstract

Hypothetically, the compact city form decreases Vehicle Miles Travels (VMT) and the reduced VMT indicates lower exposure of pedestrian crash. The evidences of empirical studies, however, have shown a mixed findings. We speculate that the mismatches between theory and empirical evidences may be caused by the spatial scale of study areas, focusing on spatial distribution feature of job and housing density. To explore the relationship between compactness built environment and pedestrian crash, the three regression model (Negative binomial regression, Log transformed linear regression and Poisson regression) were used for both spatial scale of study (city and neighborhood level) based on pedestrian accidents data from 2007 to 2013 in whole of Korea at city level and from 2010 to 2011 in Seoul at neighborhood level. The results indicate that there is different relationship between compact city and pedestrian safety depending on the spatial scale of study areas. In city level, the compact city doesn’t affect the pedestrian safety, whereas in neighborhood level the more compactness built environment, more the greater likelihood of pedestrian crash. Moreover, in neighborhood level the relationship between pedestrian crash and population density is opposite to employment density. This means that the spatial distribution of housing and job density is separated in this level. Result also describes the demographic variables is greater associated with the pedestrian crashes than compactness built environment variables. This suggests that the results of this study contribute better understanding of compact city form and its influence on pedestrian safety.