Abstract: The server 10 includes: a display control unit 14 that displays link image IM in top screen SC1; a first model generator 161 that generates a first model M1 configured to output, for each content, a first score related to a probability that the link image IM is selected by a user by machine learning based on information indicating whether link image IM is selected by a user, a user attribute of the user, and information indicating content displayed as link image IM; a user attribute acquisition unit 12 that acquires a user attribute of a target user; and an image determining unit 131 that preferentially determines an image of content having a high first score as an image associated with link image IM in top screen SC1 presented to the target user.

Abstract: The information processing device 30 includes: an extraction unit 33 for extracting a target user who has used content in a content delivery service providing the content to a user; an acquisition unit 34 for acquiring preference information related to a preference of the target user extracted by the extraction unit 33 and including a plurality of first item values related to a predetermined preference; and a tendency information generation unit 35 for generating tendency information indicating a tendency of the content based on the preference information of the target user acquired by the acquisition unit 34.

Abstract: A recommendation system includes: a first acquisition unit configured to acquire user history information; a calculation unit configured to calculate a use maturity representing maturity of use of a service for each of a plurality of users on the basis of the user history information; a second acquisition unit configured to acquire recommendation history information including target algorithm information and recommendation success/non-success information; a selection unit configured to select a target algorithm on the basis of the recommendation history information of a user group having a use maturity corresponding to the use maturity of the target user among the plurality of users; and a recommendation unit configured to determine a content to be recommended to the target user using the selected target algorithm and output information representing the determined content.