Server selection on the World Wide Web

We evaluate server selection methods in a Web environment, modeling a digital library which makes use of existing Web search servers rather than building its own index. The evaluation framework portrays the Web realistically in several ways. Its search servers index real Web documents, are of various sizes, cover different topic areas and employ different retrieval methods. Selection is based on statistics extracted from the results of probe queries submitted to each server. We evaluate published selection methods and a new method for enhancing selection based on expected search server effectiveness. Results show CORI to be the most effective of three published selection methods. CORI selection steadily degrades with fewer probe queries, causing a drop in early precision of as much as 0 05 (one relevant document out of 20). Modifying CORI selection based on an estimation of expected effectiveness disappointingly yields no significant improvement in effectiveness. However, modifying C...

• Type: Conference
• Year: 2000
• Where: DL
• Authors: Nick Craswell, Peter Bailey, David Hawking
• Keywords: Digital Library, DL 2000, Search Server, Selection, Selection Methods