Result Ranking for Structured Queries against XML Documents.
Torsten Schlieder, Holger Meuss · 2000
XML allows to represent both content and structure of documents. Querying XML data therefore requires a combination of a formal query language with the concept of relevance used in Information Retrieval. In this paper we present such a combination: First, we review Tree Matching as a simple and elegant means to formulate queries without knowing the exact structure of the data. Second, we propose a dynamic document concept by deciding on the document boundaries at query time. Third, we marry structured queries with term-based ranking by extending the term concept to structural terms which include substructures of queries and documents. We show how the notions of term frequency and inverse document frequency can be adopted to dynamically dened documents and structural terms. We introduce an ecient technique to calculate both term frequencies and inverse document frequencies at query time. By adjusting parameters of the retrieval process we are able to model two contrary approa...