ABSTRACT

The traditional Web is evolving into the Web of Data, which gathers huge collections of structured data over distributed, heterogeneous data sources. Live queries are needed to get current information out of this global data space. In live query processing, source selection deserves special attention, because it allows us to identify the sources that most likely contain relevant content. Due to the semantic heterogeneity of the Web of Data, however, it is not always easy to assess relevancy. Context information might help in interpreting the user needs. Moreover, besides relevancy, another important criterion for selecting sources is the quality of data they contain. In this paper, we discuss how context and quality metadata can be exploited to improve source selection.