Data analysis of roadway attributes´ influences upon speed of small car on mountain highway through clustering algorithm

On mountain highways, excessive speeding appears to be the major factor that causes fatal traffic accidents. In order to find out the most significant attributes that affects the vehicle speed so that countermeasures could be applied. Therefore, based on the actual traffic data collected from black spots in four provinces of southwestern China; this paper investigated the significant roadway attributes that influence the speed of small cars on mountain highways through Two step clustering algorithm, which is capable of clustering both categorical and continuous attributes. Through experiments, it shows that “material of roadway” and “presence of protective facilities at roadside” are two major attributes that affect the vehicle speed; furthermore, “material of roadway” contributes relatively more on affecting vehicle speed.