低能见度水平下行人交通事故严重程度及异质性分析

为探究在低能见度水平下影响行人事故伤害严重程度的因素, 并分析可能存在的异质性。以某市6 405起行人-机动车交通事故为研究对象, 分别研究高、低能见度水平下机动车-行人事故中行人伤害严重程度影响因素, 建立均值异质性的随机参数Logit模型并通过弹性分析定量分析显著变量对行人受伤情况的影响程度。结果表明, 高、低能见度下影响行人伤害严重程度的因素存在明显差异。(1)低能见度情况下男性驾驶员、高龄行人、卡车、沥青路面、凌晨、较暗的照明条件等因素会增加行人伤害严重程度。(2)低能见度情况下卡车和凌晨这2个因素具有随机参数特征, 分别使行人死亡的概率增加了4.39%和2.67%;此外, 当事故涉及卡车和26~35岁行人这2个因素时会增大行人死亡的概率; 而当夜间有路灯照明与凌晨这2个因素共同作用时行人死亡的可能性降低。(3)高能见度情况下未发现具有异质性的影响因素, 但发现男性行人和摩托车等因素会增大事故严重程度; 而驾驶员年龄、沥青路面、周末和地形等因素对事故严重程度并没有显著影响。 

An Analysis of Severity and Heterogeneity of Pedestrian Traffic Accidents Under Low Visibility Environment

This work studies the factors affecting the severity of pedestrian accidents under low visibility levels and investigates the possible heterogeneity. Taking 6 405 motor vehicle-pedestrian accidents in a city as the object, a random parameter Logit model with heterogeneity in means is established to investigate the factors influencing the severity of pedestrian injuries under high and low visibility levels. Elasticity analysis is used to quantify the influences of significant variables on pedestrian injuries. The results show that there are significant differences in the factors affecting severity of the pedestrian injury under high and low visibility.(1) Male drivers, elderly pedestrians, trucks, asphalt roads, early morning hours, and dark lighting conditions increase the severity of pedestrian injuries under low visibility.(2) Trucks and early morning hours have random parameters under low visibility, which increases the probability of pedestrian death by 4.39% and 2.67%, respectively. Besides, accidents involving trucks and pedestrians at the age from 26 to 35 will increase pedestrian fatalities, and its probability decreases as the combination of street lighting and early morning hours.(3) No heterogeneous factors are found under high-visibility conditions; however, factors such as male pedestrians and motorcycles are found to increase the severity of the accidents. Additionally, factors such as the age of the driver, asphalt road, weekend, and terrain have no significant impact on the severity of the accident.