Rewriting queries for web searches that use local expressions

Abstract

Users often enter a local expression to constrain a web search to a geographical place. Current search engines' capability to deal with expressions such as "close to" is, however, limited. This paper presents an approach that uses topological background knowledge to rewrite queries containing local expressions in a format better suited to standard search engines. To formalize local expressions, the Region Connection Calculus (RCC) is extended by additional relations, which are related to existing ones by means of composition rules. The approach is applied to web searches for communities in a part of Switzerland which are "close to" a reference place. Results show that query rewriting significantly improves recall of the searches. When dealing with approx. 30,000 role assertions, the time required to rewrite queries is in the range of a few seconds. Ways of dealing with a possible decrease of performance when operating on a larger knowledge base are discussed. © Springer-Verlag Berlin Heidelberg 2011.