Preface

This volume contains the papers presented at IIR 2015 (the 6th Italian Infor-
mation Retrieval Workshop) held on 25-26 May, 2015, in Cagliari.
     The purpose of the Italian Information Retrieval Workshop (IIR) is to
provide a meeting forum for stimulating and disseminating research in Informa-
tion 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 2015 is the 6th edition of the Italian Information Retrieval Workshop.
It took place on May 25-26, 2015 at the Tiscali Campus in Cagliari, Italy.
Tiscali was also the main sponsor of this event.
     The general chairs were Domenico Dato (Tiscali) and Raffaele Perego (ISTI-
CNR).
     For this edition, the committee (co-chaired by Paolo Boldi, Università degli
Studi di Milano, and Fabrizio Sebastiani, Consiglio Nazionale delle Ricerche
(CNR), Italy, and Qatar Computing Research Institute) decided to accept 27
papers. The program also included two invited talks, by Renato Soru (Tiscali)
and by Fabrizio Silvestri (Yahoo!).

   The program co-chairs wish to thank all the members of the Program Com-
mittee (see below) as well as the local organizers (Local arrangements: Gian-
luca Nonnis (Tiscali), Webmaster: Franco Maria Nardini (ISTI-CNR), Publicity:
Diego Ceccarelli (ISTI-CNR)).

   Program Committee

 – Giambattista Amati (Fondazione Ugo Bordoni)
 – Roberto Basili (Università di Roma Tor Vergata)
 – Giacomo Berardi (Consiglio Nazionale delle Ricerche)
 – Gloria Bordogna (Consiglio Nazionale delle Ricerche)
 – Claudio Carpineto (Fondazione Ugo Bordoni)
 – Fabio Crestani (Università della Svizzera Italiana)
 – Danilo Croce (Università di Roma Tor Vergata)
 – Gianmarco De Francisci Morales (Yahoo! Labs)
 – Giorgio Maria Di Nunzio (Università di Padova)
 – Andrea Esuli (Consiglio Nazionale delle Ricerche)
 – Nicola Ferro (Università di Padova)
 – Marco Gori (Università di Siena)
 – Pasquale Lops (Università di Bari)
 – Diego Marcheggiani (Consiglio Nazionale delle Ricerche)
 – Massimo Melucci (Università di Padova)
 – Stefano Mizzaro (Università di Udine)
 – Alejandro Moreo Fernandez (Consiglio Nazionale delle Ricerche)
 – Alessandro Moschitti (Qatar Computing Research Institute)
 – Cataldo Musto (Università di Bari)


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 – Gabriella Pasi (Università di Milano Bicocca)
 – Marco Pennacchiotti (eBay)
 – Giovanni Semeraro (Università di Bari)
 – Fabrizio Silvestri (Yahoo! Labs)
 – Gabriele Tolomei (Yahoo! Labs)
 – Nicola Tonellotto (Consiglio Nazionale delle Ricerche)
 – Marco Turchi (Fondazione Bruno Kessler)
 – Rossano Venturini (Università di Pisa)
 – Giovanni Zappella (Amazon)
 – Guido Zuccon (Queensland University of Technology)


    NOTE: Copyright of all papers is held by the author(s). Copying permitted
for private and academic purposes. This volume is published and copyrighted by
its editors.


Cagliari, 20 July 2015                                      Paolo Boldi and Fabrizio Sebastiani




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