Making close to Suitable for Web Search A Comparison of Two Approaches

In this paper we compare two approaches to model the vague german spatial relation in der Nähe von (English: ”close to”) to enable its usage in (semantic) web searches. A user wants, for example, to find all relevant documents regarding parks or forestal landscapes close to a city. The problem is that there are no clear metric distance limits for possibly matching places because they are only restricted via the vague natural language expression. And since human perception does not work only in distances we can’t handle the queries simply with metric distances. Our first approach models the meaning of these expressions in description logics using relations of the Region Connection Calculus. A formalism has been developed to find all instances that are potentially perceived as close to. The second approach deals with the idea that everything that can be reached in a reasonable amount of time with a given means of transport (e.g. car) is potentially perceived as close. This approach uses route calculations with a route planner. The first approach has already been evaluated. The second is still under development. But we can already show a correlation between what people consider as close to and time needed to get there.