Storage (24) stores therein a teacher model (54) that is a target image (50) with a teacher annotation (52), which specifies the target image (50), assigned thereto. An inferring section (32) assigns based on the teacher model (54) an inferred annotation (82) to an inspection image (80) belonging to the same category to which the target image (50) belongs. The inferred annotation (82) is a result of inference from the inspection image (80) based on the teacher model (54). An aiding section (34) aids a human to determine whether or not the inferred annotation (82) specifies the inspection image (80). A correcting section (36) generates a corrected model (86) in a manner to add a corrected annotation (84) to the inferred annotation (82) so that the inspection image (80) is specified.