A Factor Analysis of the Traffic Accident Frequency by Type in Japanese Major Road Sections

This study aims to identify influencing factors of traffic accidents in Japanese major road through factor analysis and regression analysis for each accident type, considering their characteristics of rare event. The database consists of 5-year accident record and relevant road traffic condition data in major road sections in Aichi Prefecture which includes the third largest conurbation area of Japan. From the results of the factor analysis, a trend of high accident rates in broad urban arterials is confirmed, and rear-end or side collisions are widely distributed in suburban areas. From the regression analysis, results revealed that the degree of impact by traffic volume is dependent on accident type, and suggested several factors related to visibility have an influence on turning and side collisions. Finally, this paper suggests that improving quality of traffic flow on major roads by ensuring proper intersection spacing is important for establishing a safer road network.