INFORMATION PROCESSING SERVER, PROCESSING METHOD FOR INFORMATION PROCESSING SERVER, AND NON-TRANSITORY STORAGE MEDIUM

An information processing server (10; 40) is configured to acquire target vehicle data having traveling conditions of target vehicles (2) and position information of the target vehicles (2) on a map, recognize, based on the target vehicle data, an unstable behavior position (D) on the map where at least one of the target vehicles (2) exhibits unstable behavior, measure an occurrence count of the unstable behavior positions (D) within a predetermined period in a mesh (50) preset on the map, enlarge the mesh (50) to include the unstable behavior positions (D) within the predetermined period such that the occurrence count of the unstable behavior positions (D) is equal to or larger than a first threshold, and store the mesh (50) and the unstable behavior positions (D) of the mesh (50) in a storage database (16) related to each other.