Abstract
This paper focuses on the driver's impression to the false alarms of driving support system related to the intelligent transport systems. The hypothesis is proposed that the driver tends to have not so bad impression to false alarms when the driver finds it difficult to detect the phenomena that system needs to alarm, compared with the other situation that driver finds it easy to do that. For proving this hypothesis, experiments of tracking previous vehicle at the same headway distance with correcting the headway by alarm system, which has some false alarms, are carried out. According the analysis of these experiments, our hypothesis is partially verified
