Classification of Time Series Trend and Seasonal Variation of Traffic Accidents

Analysis of Vehicle to Vehicle Accidents in Kanagawa Prefecture

Abstract

This paper shows the result of time series analysis of vehicle to vehicle accidents in cities in Kanagawa prefecture occurred between 2007 and 2017. In this analysis, we focused on times series trend and seasonal variation of traffic accidents. The accident risk in each city was separated into trends and seasonal components with state space model, and cities were classified based on these trends and seasonal variations. The results of this analysis were as follows. (1) The number of traffic accidents was decreasing monotonously in long-term but slightly increased in 2017. (2) The risk of traffic accidents increased in the latter half of the year in most cities except for Kamakura city, where it increased a lot in summer because of its regional characteristic as a resort area.