Analysis on Characteristics of Traffic Accidents in Nagano (Second Report)-Cluster Analysis-

In previous report, the fatal accidents in hilly and mountainous area are paid attention to Nagano prefecture using statistical accident data analysis. Also, it was found that Wakayama and Yamanashi prefectures etc. belong to same cluster. This paper analyzed the comparison among these prefectures to clarify Nagano's and each cluster’s characteristics of accidents in detail. Principal component analysis was performed to clarify the characteristics of each cluster and remarkable accidents. Furthermore, the feature was verified by classifying and investigating fatal accidents in Nagano occurred in 2016. As a result, remarkable accidents of Nagano were vehicle to vehicle and vehicle alone accidents on the road with up-down slope and curve in hilly and mountainous areas. It was found that approximately 19% of fatal accidents in Nagano were these types of accidents. In addition, the principal component analysis indicates Wakayama and Yamanashi have the same characteristics of accidents as Nagano. This method for accident analysis is valuable to find out characteristics and their true causes toward zero accidents in local areas © 2019. Society of Automotive Engineers of Japan, Inc. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike license