Toponym Resolution Based on Surface Difference among Candidates

Abstract

There have been many researches on toponym resolution as an approach to solve the unknown word problem. In this paper we propose an area candidate estimation method for toponyms, to assign area information to unknown toponyms. Our aim is to expand the target toponyms to non-restricted domains. Thus we aim for a simple system avoiding the use of gazeteers and context information. Our method is based only on surface information to estimate area candidates to where the toponyms may belong. Toponym resolution can be difficult because of linguistic or geographic reasons. Focusing on the surface difference among probable countries, we constructed a system containing a reduction phase for a rough examination and a selection phase for a detailed examination among them. By our effective combination of these two phases, we succeeded in gaining high precision rate maintaing high recall rate.