Analysis of Environmental Factors on Intersection Accidents

In recent years, the number of fatal traffic accidents has been on the rise in Taiwan, with a total of 2865 fatalities in 2019, representing a 3% increase from the previous year, and indicating an urgent need for the improvement of Taiwan’s traffic conditions. This research focuses on the three-way intersections on provincial roads. In Taiwan, such three-way intersections account for more than 70% of all intersections on provincial roads. From 2018 to 2019, there were 41,137 accidents at three-way intersections, accounting for about 50% of the traffic accidents in Taiwan. Relevant research in Taiwan has been mostly focused on driver characteristics and other factors were less addressed. In this study, we looked into the environmental factors, conducted analysis and the results were proposed for future roadway safety improvements. This study uses a regression model for analysis, in which the dependent variable is the number of traffic accidents at each intersection. However, for 68% of the three-way intersections surveyed, the number of traffic accidents recorded during the observation period was zero. Therefore, this study uses zero-inflated models to construct a model to identify important variables that affect the severity of traffic accidents at three-way intersections. The research results show that two types of factors are related to the risk of traffic accidents at three-way intersections. The first type includes the width of the provincial road, the width of the shoulder, the width of the dividing line and the number of lanes, while the second type relates to the presence of convenience stores, gas stations, supermarkets, and other attractions, such as public retail markets at the intersection.