Unexpectedness prediction sensitivity determination means

Unexpectedness prediction sensitivity determination means (2) in accordance with information received from the plurality of intersections to the vehicle C, the horizontal driving behavior criterion when turning around the intersection of the driver for each intersection. Next, unexpectedness prediction sensitivity determination means (2) crossing each other in the same horizontal intersection corresponding information in accordance with the determined standard driving behavior of the driver, it is determined unexpectedness driver when turning around the intersection prediction sensitivity.