对于特定长度的高速公路，公路上的车辆密度（每100米车辆的数目）与事故发生的数量有关。一般认为，事故的数量随某一点的车辆密度的增加而增加。然而，当车辆密度超过某一特定值时，由于拥-For a particular length of highway, roads on the vehicle density (per 100 meters the number of vehicles) and the number of accident-related. Is generally believed that the number of accidents with a point density of vehicles increases. However, when the vehicle density of more than a particular value, because of congestion