Abstract: A traffic congestion determination device includes an acquisition unit configured to acquire a total number of automobiles for each mesh obtained by virtually dividing a determination target region of traffic congestion and for each unit time, and a determination unit configured to determine whether occurrence of traffic congestion is sudden for each of the meshes based on the acquired total number of automobiles for each of the meshes and unit time.

Abstract: An estimation method includes acquiring sensor information acquired by a sensor mounted on a first vehicle belonging to a vehicle line, acquiring position information on a location of the first vehicle, and estimating a cause of the vehicle line by using the sensor information and the position information. The estimating of the cause includes estimating the cause by using information on a facility or a feature present near the first vehicle, information indicating a state of the first vehicle, information on an object present ahead of the first vehicle included in the sensor information, or information on a road that affects traveling. The information on the facility or the feature is searched based on the position information, the information on the object is estimated based on the sensor information, and the information on the road is searched based on the position information.

Abstract: A position estimation unit 25 estimates, for each movement in a predetermined section, a plurality of position candidates of a position estimation target on the basis of position information and sensor information. A position determination unit 26 evaluates, for each movement in the predetermined section, on the basis of the plurality of position candidates of the position estimation target obtained by the movement in the predetermined section, whether the position information used to estimate the position candidates has an error caused by any of a position of a GPS satellite, a position of a mobile body in a real space, or the mobile body or does not have any error caused thereby.

Abstract: A state estimation method executed by a state estimation apparatus including a processor and a memory storing program instructions that cause the processor to estimate a state related to congestion on a subject lane, includes acquiring a state related to congestion of a monitoring vehicle traveling on a non-subject lane, counting a number of vehicles traveling on the subject lane, the vehicles being overtaken by the monitoring vehicle or being oncoming vehicles passed by the monitoring vehicle, and estimating the state related to the congestion on the subject lane, using the state related to the congestion of the monitoring vehicle and the number of vehicles. In the estimating, when the number of the vehicles is equal to or greater than a threshold value according to the state related to the congestion of the monitoring vehicle, the state related to the congestion on the subject lane is estimated as traffic congestion.