Keyword acquiring device, content providing system, keyword acquiring method, a computer-readable recording medium and content providing method

A content providing system, comprising:

• a tree storage unit that stores a keyword tree obtained by performing hierarchization according to the number of appearances and relevance in advance using a keyword associated with content as a node;
• a log storage unit that records a keyword associated with content previously selected by a user as a log;
• a partial tree extracting unit that extracts a plurality of keywords based on a predetermined condition from a log corresponding to a certain user recorded in the log storage unit, and extracts a partial tree including the extracted keywords from the keyword tree;
• and
• a keyword acquiring unit that acquires a keyword in a node having no other lower node as a keyword related to the user's interest;
• a keyword storage unit that stores content and a keyword in advance in association with each other;
• and
• a content providing unit that provides content corresponding to the keyword acquired by the keyword acquiring unit to the user;
• wherein the keyword acquiring unit sorts each node of the partial tree for every two or more nodes having the same upper node based on a count number representing the number of keywords recorded in the log storage unit, explores the plurality of partial trees in order starting from a partial tree which is large in a count number of a highest node, and acquires a predetermined number of keywords from the partial trees.

A keyword acquiring method performed by a keyword acquiring device including a tree storage unit that stores a keyword tree obtained by performing hierarchization according to the number of appearances and relevance in advance using a keyword associated with content as a node, the method comprising:

• recording a keyword associated with content previously selected by a user as a log;
• extracting a plurality of keywords based on a predetermined condition from a log corresponding to a certain user recorded in the log;
• extracting a plurality of partial tree including the extracted keywords from the keyword tree;
• acquiring a keyword in a node having no other lower node as a keyword related to the user's interest;
• sorting each node of the partial tree for every two or more nodes having the same upper node based on a count number representing the number of keywords recorded in the log storage unit;
• exploring the plurality of partial trees in order starting from a partial tree which is large in a count number of a highest node;
• and
• acquiring a predetermined number of keywords from the partial trees.

A computer-readable recording medium in which a computer program is recorded, the computer program causes a computer, which includes a tree storage unit that stores a keyword tree obtained by performing hierarchization according to the number of appearances and relevance in advance using a keyword associated with content as a node, to execute:

• recording a keyword associated with content previously selected by a user as a log;
• extracting a plurality of keywords based on a predetermined condition from a log corresponding to a certain user recorded in the log;
• extracting a partial tree including the extracted keywords from the keyword tree;
• acquiring a keyword in a node having no other lower node as a keyword related to the user's interest;
• sorting each node of the plurality of partial trees for every two or more nodes having the same upper node based on a count number representing the number of keywords recorded in the log storage unit;
• exploring the partial tree in order starting from a partial tree which is large in a count number of a highest node;
• and
• acquiring a predetermined number of keywords from the partial trees.

A content providing method performed by a content providing system including a tree storage unit that stores a keyword tree obtained by performing hierarchization according to the number of appearances and relevance in advance using a keyword associated with content as a node and a keyword storage unit that stores content and a keyword in advance in association with each other, the method comprising:

• recording a keyword associated with content previously selected by a user as a log;
• extracting a plurality of keywords based on a predetermined condition from a log corresponding to a certain user recorded in a log storage unit;
• extracting a partial tree including the extracted keywords from the keyword tree;
• acquiring a keyword in a node having no other lower node as a keyword related to the user's interest;
• providing content corresponding to the keyword acquired in the acquiring of the keyword to the user;
• sorting each node of the partial tree for every two or more nodes having the same upper node based on a count number representing the number of keywords recorded in the log storage unit;
• exploring the plurality of partial trees in order starting from a partial tree which is large in a count number of a highest node;
• and
• acquiring a predetermined number of keywords from the partial trees.