Included are a 2D processing unit 11 that generates 2D latitude and longitude information by dimensionally compressing a feature vector generated from target information, and a map generation unit 12 that generates a 2D map in which a plurality of pieces of target information is plotted on a 2D plane based on a plurality of pieces of latitude and longitude information generated for a plurality of pieces of target information. A plurality of pieces of target information is plotted based on a feature vector in a coordinate system of a closed space having finite latitude and longitude values, so that a plot position of target information can be appropriately determined in a wide coordinate space based on latitude and longitude without performing processing such as defining a finite target area in a coordinate system of an infinite open space, and a state in which pieces of target information having a high similarity are plotted in a shape of a mass at close positions is likely to occur appropriately at a plurality of locations.