What can a web bag discover for you?

摘要

Sets and bags are closely related structures. A bag is different from a set in that it is sensitive to the number of times an element occurs while a set is not. In this paper, we introduce the concept of web bag in the context of the web warehouse project called Whoweda (Warehouse of Web Data). Informally, a web bag is a web table which allows multiple occurrences of identical web tuples. We have used web bag to discover useful knowledge from a web table such as visible documents (or web sites), luminous documents and luminous paths. In this paper, we formally discuss the semantics and properties of web bags. We design formal algorithms for the construction of a web bag and its schema. In addition, we also provide formal algorithms for various types of knowledge discovery in a web warehouse using web bag and illustrate them with examples.