Identification and Ranking of High Pedestrian Crash Zones for Allocation of Safety Funds
Source: Transportation Research Board
"Identifying and ranking high pedestrian crash zones plays a key role in developing efficient and effective strategies to enhance pedestrian safety. This paper presents 1) a methodology to study the spatial patterns of pedestrian crashes in order to identify high pedestrian crash zones, and 2) an evaluation of methods to rank these high pedestrian crash zones. The Geographical Information Systems (GIS) based methodology to identify high pedestrian crash zones includes geocoding crash data, creating crash concentration maps, and then identifying high pedestrian crash zones. The Simple Method or the Kernel Method is generally used to generate crash concentration maps based on density values. Methods such as crash frequency, crash density, and crash rate as well as composite methods such as sum-of-the-ranks and crash score methods are used to rank the selected high pedestrian crash zones. The use of the GIS based methodology and ranking of high pedestrian crash zones is illustrated using the Las Vegas metropolitan area as the study area. Crash data collected for a five year period (1998 to 2002) were address matched using the street name / reference street name location reference system. A concentration map was then created using the Kernel Method as it facilitates the creation of a smooth density surface when compared to the Simple Method. Twenty two linear high crash zones and 7 circular high crash zones were then identified. The GIS based methodology reduced the subjectivity in the analysis process. Results obtained from the evaluation of methods to rank high pedestrian crash zones show a significant variation in ranking when individual methods were considered. However, rankings of high pedestrian crash zones were relatively consistent with little to no variation when sum-of-the-ranks method and crash score method were used. Thus, composite methods are recommended for use in ranking high pedestrian crash zones instead of individual methods."
