Combining information extraction and data integration in the estest system

We describe an approach which builds on techniques from Data Integration and Information Extraction in order to make better use of the unstructured data found in application domains such as the Semantic Web which require the integration of information from structured data sources, ontologies and text. We describe the design and implementation of the ESTEST system which integrates available structured and semi-structured data sources into a virtual global schema which is used to partially configure an information extraction process. The information extracted from the text is merged with this virtual global database and is available for query processing over the entire integrated resource. As a result of this semantic integration, new queries can now be answered which would not be possible from the structured and semi-structured data alone. We give some experimental results from the ESTEST system in use.