GeoVSM: An Integrated Retrieval Model for Geographic Information

Geographic information exists in multiple forms, such as cartographical maps, images, and texts. Effective retrieval systems for geographic information are currently studied by both geospatial information scientists and library/information scientists. The two groups take quite different approaches, which have rarely been explicitly compared and connected. This paper discusses the advantages and limitations of current geographic information retrieval (GIR) and textual information retrieval (IR) systems in dealing with multimedia geographic information, and proposes a new retrieval model, called GeoVSM (Geographic + Vector Space Model), which integrates coordinate-based geographic indexing with the keyword-based vector space model in representing information space. Document ranking by relevance is supported by document-query similarity measures, taking into account the degree of relevance in both the spatial domain and the thematic domain. To support visual querying and browsing, the GeoVSM model recognizes the fundamental differences in the dimensionality and configuration of geographic space and thematic space, and demands multi-view visual interfaces based on a “world’ metaphor and a “desktop” metaphor. As an example of such interfaces, GeoVIBE is presented, which supports a coordinated GeoView and a Vibe View for smooth integration of two browsing strategies using geographic clues as well as thematic clues provided by users.