Integrating data from maps on the world-wide web

A substantial amount of data about geographical entities is available on the World-Wide Web, in the form of digital maps. This paper investigates the integration of such data. A three-step integration process is presented. First, geographical objects are retrieved from Maps on the Web. Secondly, pairs of objects that represent the same real-world entity, in different maps, are discovered and the information about them is combined. Finally, selected objects are presented to the user. The proposed process is efficient, accurate (i.e., the discovery of corresponding objects has high recall and precision) and it can be applied to any pair of digital maps, without requiring the existence of specific attributes. For the step of discovering corresponding objects, three new algorithms are presented. These algorithms modify existing methods that use only the locations of geographical objects, so that information additional to locations will be utilized in the process. The three algorithms are compared using experiments on datasets with varying levels of completeness and accuracy. It is shown that when used correctly, additional information can improve the accuracy of location-based methods even when the data is not complete or not entirely accurate.