This workshop was open, but jointly organized by the Working Groups 3 and 4 of the COST Action KEYSTONE. This is dedicated to launching and establishing a cooperative network of researchers, practitioners, and application domain specialists working in fields related to semantic data management; the semantic web; information retrieval; artificial intelligence; machine learning; and natural language processing, that coordinates collaboration among them to enable research activity and technology transfer in the area of keyword-based search over structured data sources. In fact, keyword-based search has become the de facto standard for information discovery in the modern Web. Its simplicity to novice users matches the simplicity with which they nowadays publish information in the world's largest database. To answer keyword queries, existing search engines rely on effective indexes of the content that allow them to return the documents that best match the user's search criteria. This generally leaves out the structure of the data, its semantic dimension, as well as the social aspects to which it may relate. We believe that, in order to exploit the full potential of the Web, structured and rich data will have to receive the same search and retrieval capabilities as the text data from Web documents. However, due to their highly structured nature, the rich semantics, and the data structures by which they are typically managed, a great deal of issues needs to be addressed. As the problem is in general of a multifaceted nature, it requires synergies from many different disciplines. The papers in this workshop have been peer-reviewed by renowned academics that accepted to integrate our
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Vagan Terziyan, University of Jyvaskyla, Finland To these colleagues, and also the authors that submitted papers and the audience at the workshop, we would like to extend our sincere appreciation.
Workshop chairs