Abstract
In the search service by a certain keyword, it is difficult to connect efficiently reflecting an intention of both a consumer and a donor and the purpose now. In concrete language and the objective physics characteristic of goods, it is hard to express the selection standard which especially the consumer has inner, the feature which especially a donor wants to advertize. Moreover, when two or more Rough Sets, The ambiguous purpose goods of an on-line shop donor exists and the category of goods catches goods dealing with a series of flows in very various sites, since it is not what a mainstream search engine assists with the purchase of goods, and the determination of purchase goods is urged to, the portion for which efficiency depended on contingency bad is large / use in the state with a user’s ambiguous purpose / now.
