Everett and Cater's retrieval topology

✍ Scribed by Egghe, Leo ;Rousseau, Ronald

• Book ID: 101249159
• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 44 KB
• Volume: 48
• Category: Article
• ISSN: 0002-8231
• DOI: 10.1002/(sici)1097-4571(199705)48:5<479::aid-asi17>3.0.co;2-u

✦ Synopsis

If there exists a document D 0 in DS satisfying the following relation: Sir:

In this letter, we demonstrate that there is an error in Everett ∀Q √ QS, ∃ c(Q) ú 0, such that ∀D √ DS: and Cater's article about retrieval topologies 1992). To make this note self-contained, we recall the following definitions adapted from Everett and Cater (1992).

A retrieval model is a triple (DS, QS, sim), consisting of a then DS is compact for the retrieval topology. document space DS, a query space QS, and a non-negative realvalued similarity function

Consider an open covering (V i ) i of DS. At least one of these V i must contain D 0 . Hence D 0 belongs to a basic open set of the form The retrieval topology is the smallest topology on DS which contains all the sets of the form R(Q, r) Å {D √ DS: sim(D, Q) ú r}, with Q √ QS and r √ ‫ޒ‬ / . Recall that elements of a