KEYWORD ACQUISITION DEVICE, CONTENT PROVISION SYSTEM, KEYWORD ACQUISITION METHOD, PROGRAM, AND CONTENT PROVISION METHOD

摘要

PROBLEM TO BE SOLVED: To acquire a keyword relating to the interest of a user.SOLUTION: A keyword acquisition device including a tree storage unit which stores in advance a keyword tree obtained by defining keywords associated with contents as nodes and hierarchizing the nodes in accordance with their appearance frequencies and relevance among them, records keywords associated with contents selected in the past by users, as logs, extracts a plurality of keywords from a log corresponding to one user recorded in the logs on a basis of a predetermined condition, extracts a partial tree constituted of the extracted keywords, from the keyword tree, and acquires a keyword having no nodes in subordinates, as a keyword relating to the interest of the user.