Effects of hazard types on drivers' risk rating and hazard response in a video-based hazard perception task

Hazard perceptioniscrucial for identifying potential hazards on the road, and how quick drivers can respond to the hazard partiallyrelies on their risk rating of the hazard after they detect it. Although many studies have attempted to reveal the relationship between drivers'response latencies and their risk ratings, this relationship has not been extensivelyexplored under different hazard types. The presentstudy addresses this issue using a video-based hazard perception task.Forty novice drivers and 35 experienced drivers were recruited and 26 video clipscontaining either an overt hazard (continuous visibility) or a covert hazard (interrupted visibility) were shown to participants.Participants were asked to finish the hazard perception task first and then rated the risk level of the hazard when each video clip was replayed. Participants'confidence in their answers for risk ratings was also determined.Results showed that experienced drivers responded to overt and covert hazards faster than did novice drivers. A negative and significant correlation was found between drivers' risk ratings of covert hazards and their response latencies. Such a relationship was not found forovert hazards. More importantly, drivers rated the risk level of covert hazards higher than that of overt hazards, and higher risk ratings of covert hazards resulted in faster responses to these hazards. The findings of the present study indicate that hazard types not only influence drivers' risk ratings and response latencies but also determine theirrelationships.