Document (#32985)

Author

Crestani, F.
Wu, S.

Title

Testing the cluster hypothesis in distributed information retrieval

Source

Information processing and management. 42(2006) no.5, S.1137-1150

Year

2006

Abstract

How to merge and organise query results retrieved from different resources is one of the key issues in distributed information retrieval. Some previous research and experiments suggest that cluster-based document browsing is more effective than a single merged list. Cluster-based retrieval results presentation is based on the cluster hypothesis, which states that documents that cluster together have a similar relevance to a given query. However, while this hypothesis has been demonstrated to hold in classical information retrieval environments, it has never been fully tested in heterogeneous distributed information retrieval environments. Heterogeneous document representations, the presence of document duplicates, and disparate qualities of retrieval results, are major features of an heterogeneous distributed information retrieval environment that might disrupt the effectiveness of the cluster hypothesis. In this paper we report on an experimental investigation into the validity and effectiveness of the cluster hypothesis in highly heterogeneous distributed information retrieval environments. The results show that although clustering is affected by different retrieval results representations and quality, the cluster hypothesis still holds and that generating hierarchical clusters in highly heterogeneous distributed information retrieval environments is still a very effective way of presenting retrieval results to users.

Theme

Verteilte bibliographische Datenbanken

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5. Park, S.: Usability, user preferences, effectiveness, and user behaviors when searching individual and integrated full-text databases : implications for digital libraries (2000) 0.22

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