IIR 2013 - Italian Information Retrieval Workshop, Proceedings of the 4th Italian Information Retrieval Workshop Pisa, Italy, January 16-17, 2013

The purpose of the Italian Information Retrieval (IIR) workshop series is to provide a forum for stimulating and disseminating research in information retrieval, where Italian researchers (especially young ones) and researchers affiliated with Italian institutions can network and discuss their research results in an informal way. IIR 2013 took place in Pisa, Italy, at the National Council of Research campus on January 16-17, 2013, following the first three successful editions in Padua (2010), Milan (2011) and Bari (2012). The contributions to IIR 2013 mainly address six relevant topics: - theory - query languages and operations - image retrieval - evaluation - social media and information retrieval - semantics, natural language and applications Most submitted papers were from PhD students and early stage researchers. All the 24 submissions, both full and short original papers presenting new research results, as well as extended abstracts containing descriptions of ongoing projects or presenting already published results, were reviewed by two members of the Program Committee and 18 contributions were selected for presentation on the basis of originality, technical depth, style of presentation, and impact. Additionally to the presentations of these 18 submitted papers, IIR 2013 featured two special events. The first was an invited talk by Renato Soru, CEO of Tiscali SpA, in which the speaker addressed past, present, and future efforts by Tiscali to enter the Web search market. In particular, Soru highlighted some new features of “istella”, the soon-to-be-announced Web search engine by Tiscali, mainly addressed at covering the Italian Web space, with a special emphasis on making Italy’s cultural heritage digitally available to a wide audience. The second special event was a panel on EVALITA, an evaluation campaign which has been running biennially since 2007 and whose main goal is the evaluation of natural language processing tools for Italian. Several EVALITA task organizers have presented the main results obtained in the recent editions of the campaign and have discussed the unresolved challenges that still lie ahead of researchers, with the aim of generating awareness about the state-of-the-art in Italian NLP among IR researchers and of strengthening the relationships between the two communities. The present proceedings include the papers that were presented at IIR 2013. We hope they represent an interesting contribution to IR research in Italy, and to IR research in general