  Road accidents involving pedestrians are still too numerous in cities,
particularly at crosswalks. Many pedestrians crossed at the red light at zebras
increasing the risk of accidents, for them and for people following mimetically
them. Several studies tried to understand the causes of these illegal
road-crossing behaviours, showing an effect of age, gender but also culture.
This current study aims to understand causes of the uncertainty behaviour in
two different countries: France and Japan. Uncertainty behaviour during
road-crossing is here defined as a walking stop or a slowing down during a
road-crossing behaviour at the red light. Uncertainty happens when there is a
conflict between different information a pedestrians get, specifically between
private and social information. This uncertainty behaviour is followed either
by a speeding up to finish to cross the road or a giving-up. Our study showed
an uncertainty time longer in Japan compared to France. Japanese pedestrians
hesitated on a longer time when someone accompanied them. Being on the phone
did not have an effect on the uncertainty time. There are many more give-ups
than speed-ups, and this rate increases with the number of lanes. Moreover,
there is a tendency to speed up with the number of pedestrians already crossing
the road. This study confirms that pedestrians followed social information at
road-crossings and hesitate when they realised their errors, increasing their
risk of accidents. Understanding this, different solutions might be proposed to
avoid these unintentional illegal road-crossing behaviours.
