| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase the number of users who use charged service. <P>SOLUTION: A price variation unit (32) is price variation means for varying a current price of purchase target data to be purchased by users, and obtains user group data from means for storing the user group data, in which a first user is associated with a second user. When the first user purchases the purchase target data, a price determination unit (34) determines a price of the purchase target data for the second user associated with the first user to purchase the purchase target data so that the price differs from the current price of the purchase target data having been by the price variation unit (32), on the basis of a price of the purchase target data when the first user has purchased the purchase target data. <P>COPYRIGHT: (C)2013,JPO&INPIT |
