1. A travel pattern information obtaining device comprising: a vehicle speed identification information obtaining unit for obtaining vehicle speed identification information in order to identify vehicle speed of a vehicle on a road for a plurality of vehicles; a vehicle speed identification information classifying unit for classifying the vehicle speed identification information into a group corresponding to a motion of the vehicle, based on a distribution of the vehicle speed identification information; and a motion occurrence probability obtaining unit for obtaining an occurrence probability of the motion of the vehicle, based on the classification characterized in that the vehicle speed identification information obtaining unit obtains the vehicle speed identification information of a plurality of road sections, respectively, that are consecutive between two preset points, the vehicle speed identification information indicating the vehicle speed or required time of the road sections, the vehicle speed identification information classifying unit classifies the vehicle speed identification information of each of the road sections into the group which is systematically defined in order from the road section with the smallest number n (natural number) such that a plurality of vehicle speed identification information for a road section (n+ 1 ) obtained by theplurality of vehicles that outputted a plurality of vehicle speed identification information comprising one group for a road section n is further classified into one or more groups, and the motion occurrence probability obtaining unit obtains the occurrence probability of the motion of the vehicle on each of the road sections based on the systematic classification, the occurrence probability being dependent on the occurrence probability of the motion of the vehicle on a previous road section of the road section.