Development and Refinement of the Alameda County Pedestrian Intersection Volume Model
The purpose of this study was to create a simple equation that could be used to estimate pedestrian intersection crossing volumes along arterial and collector roadways in Alameda County, California. A pilot version of the model equation was developed in 2008. It was based on weekly pedestrian volumes collected at a sample of 50 intersections with a wide variety of surrounding land uses, transportation system attributes, and neighborhood socioeconomic characteristics. Three alternative model structures were considered, and the final recommended model had a good overall fit (adjusted-R2=0.897). Statistically-significant factors in the model included the total population within a 0.5-mile radius, number of jobs within a 0.25-mile radius, number of commercial retail properties within a 0.25-mile radius, and the presence of a regional transit station within a 0.1-mile radius of an intersection. The statistical equation had a simple structure, and it can be applied by practitioners using a basic spreadsheet program. Since the study was based on a relatively small number of intersections in one urban area, the study provided a template for additional research to determine its applicability in other areas.
The model was tested and refined in 2009. To evaluate the accuracy of the model, pedestrian volume predictions calculated from the pilot model were compared with counts that were collected at 30 additional Alameda County intersections in 2009. Validation testing showed that the model generally underestimated pedestrian volumes. In addition, it tended to be less accurate at intersections further from schools, further from transit stations, in neighborhoods with less sidewalk coverage, and in neighborhoods with more households without a motor vehicle available. Additional analysis of the 2008 and 2009 data led to several alternative models. The preferred refined model had a good fit (adjusted R-squared = 0.900), and produced estimates with similar accuracy as the model developed in 2008. Overall, the study demonstrated the value of the validation process in Alameda County and provided a framework for future pedestrian model development and testing in other communities.
Location: Alameda County, California
Project Time Period: March 2008 to October 2009
Funders: California Department of Transportation (Caltrans) and Alameda County Transportation Commission (ACTC). Work was performed at the UC Berkeley Safe Transportation Research and Education Center.
Additional Information: http://trb.metapress.com/content/c513687133247113/
The model was tested and refined in 2009. To evaluate the accuracy of the model, pedestrian volume predictions calculated from the pilot model were compared with counts that were collected at 30 additional Alameda County intersections in 2009. Validation testing showed that the model generally underestimated pedestrian volumes. In addition, it tended to be less accurate at intersections further from schools, further from transit stations, in neighborhoods with less sidewalk coverage, and in neighborhoods with more households without a motor vehicle available. Additional analysis of the 2008 and 2009 data led to several alternative models. The preferred refined model had a good fit (adjusted R-squared = 0.900), and produced estimates with similar accuracy as the model developed in 2008. Overall, the study demonstrated the value of the validation process in Alameda County and provided a framework for future pedestrian model development and testing in other communities.
Location: Alameda County, California
Project Time Period: March 2008 to October 2009
Funders: California Department of Transportation (Caltrans) and Alameda County Transportation Commission (ACTC). Work was performed at the UC Berkeley Safe Transportation Research and Education Center.
Additional Information: http://trb.metapress.com/content/c513687133247113/
