Spatial Information Retrieval

DEFINITION Spatial Information Retrieval (SIR) refers to providing access to geo-referenced sources by indexing, searching, retrieving, and browsing [1]. SIR is an interdisciplinary topic involving geospatial information science, data mining, computer network, cognition, and cartography. An example of SIR query could be “Where are the Italian restaurants within 500 meters around a lake park?” Figure 1 (a) illustrates the spatial distribution around the park: Shaded area represents the park; triangles represent restaurants; the red triangles represent those providing Italian food. To answer the question, spatial entities, such as restaurants and the park, are abstracted to a point described in [x, y] coordinates. To execute the query, both Information Retrieval algorithm and spatial relationship analysis are needed: 1) locate the area of interest where a circle has a radium of 500 meters (Figure 1b); 2) filter out restaurants from other objects (represented by the point in Figure1); 3) search the restaurant index to identify the keyword 'restaurant types' with 'Italian food'; 4) a list of restaurants, ranked by the distance to the park, is sent back to users.