Categorical principal component analysis (CATPCA) of pedestrian crashes in Central Florida

Abstract

This research investigates the characteristics and contributing causes of pedestrian crashes that occurred in Central Florida over a 5 year-period at intersections and mid-block crossings along roadway segments. The factors contributing to pedestrian crashes were classified into four main categories: location characteristics, pedestrian factors, driver/vehicle characteristics, and environmental-related factors along with their corresponding crash characteristics. Categorical Principal Components Analysis (CATPCA) was applied to understand the structure of a set of variables and to reduce the dimensionality of the dataset to a predefined number of dimensions and components. CATPCA analysis revealed that four dimensions accounted for almost 50% of the model indicating strong positive relationships between datasets with driver and pedestrian characteristics along with their corresponding crash characteristics relatively significant than the location and the environmental characteristics. The analysis showed that majority of the intersection crashes were during nighttime with pedestrians under influence and failing to yield to the right of way (ROW). They included mainly left-turn and right-turn crashes. In addition, drivers were also found at fault due to vision issues resulting from absence of lighting at intersections and categorized as failure to yield to the ROW. At midblock locations, major crash types were through moving vehicles hitting pedestrians crossing and walking along the roadway especially during nighttime conditions. However, majority of the crashes were at locations away from the designated crossings likely due to the long distances between legal crossing locations and pedestrian’s failure to utilize them. The findings of this research and examining the factors affecting pedestrians’ crash likelihood and injury severity can lead to better crash mitigation strategies, countermeasures and policies that would alleviate this growing problem in Central Florida.