1. A recommendation information generation apparatus comprising: a vector acquisition unit that acquires a user characteristic vector of each of users; a similarity calculation unit that calculates the degree of similarity between the users based on the user characteristic vector of each of the users that is acquired by the vector acquisition unit; a selection unit that selects a similar user who is similar to a first user based on the degree of similarity calculated by the similarity calculation unit; and a generation unit that generates recommendation information for the first user based on the characteristic vector of the similar user selected by the selection unit.