| 摘要 |
<p>A grouping device (1) for affiliating or disaffiliating a user with respect to one or more groups according to the state of the user is provided with a change storage unit (13) for associating and storing first attribute values representing the state of the user at a first time-point, a key generated on the basis of second attribute values representing the state thereof at a second time-point, and member list differences of groups with respect to which the user is to be affiliated or disaffiliated. In addition, the grouping device (1) is provided with a two time-point context acquisition unit (111) for acquiring a two time-point context including the current attribute values of the user, an information search unit (12) for searching for the member list differences corresponding to the key that has been generated on the basis of the past attribute values and the current attribute values included in the two time-point context from the change storage unit (13), and a transmission unit (121) for transmitting the member list differences.</p> |
