Query expansion for effective geographic information retrieval

Abstract

We developed two methods for monolingual Geo-CLEF 2008 task. The GCEC method aims to test the effectiveness of our online geographic coordinates extraction and clustering algorithm, and the WIKIGEO method wants to examine the usefulness of using the geographic coordinates information in Wikipedia for identifying geo-locations. We proposed a measure of topic distance to evaluate these two methods. The experiments results show that: 1) our online geographic coordinates extraction and clustering algorithm is useful for the type of locations that do not have clear corresponding coordinates; 2) the expansion based on the geo-locations generated by GCEC is effective in improving geographic retrieval; 3) Wikipedia can help in finding the coordinates for many geo-locations, but its usage for query expansion still needs further study; 4) query expansion based on title only obtained better results than that on the title and narrative parts, even though the latter contains more related geographic information. Further study is needed for this part. © 2009 Springer Berlin Heidelberg.