Preface Omar Alonso1 , Marc Najork2 and Gianmaria Silvello3 1 Instacart, 50 Beale St Ste 600, San Francisco, CA 94105 USA 2 Google Research, Google LLC 1600 Amphitheatre Parkway Mountain View, CA 94303 USA 3 University of Padua, Department of Information Engineering, Via Gradenigo 6/b, Padova, 35131 Italy Abstract This is the preface to the proceedings of the 2nd International Conference on Design of Experimental Search & Information REtrieval Systems (DESIRES) that run in Padua (Italy) from 15 September 2021 to 18 September 2021. Scope of the Conference are often papers that offer long-term value to the field and should be widely disseminated. DESIRES values in- DESIRES (Design of Experimental Search & Information novation, experience-based insight, and vision. REtrieval Systems) is a systems-oriented conference, com- DESIRES is about discussing, learning, and thinking plementary in its mission to the mainstream Information about new ideas. Hence, no discussion will be shut off Access and Retrieval conferences like SIGIR, ECIR, and with the "let’s take this offline" key-phrase; if we discuss other symposiums focusing on specific aspects of IR such longer than expected, we just slightly reschedule the as ICTIR or CHIIR, emphasizing the innovative technical following talks. aspects of search and retrieval systems. DESIRES is a single-track conference, and to encour- DESIRES gathers researchers and practitioners from age authors to submit only their best work, each person both academia and industry to discuss the latest inno- can be an author or co-author of only a single paper or vative and visionary ideas in the field. The goal of this prototype (plus one abstract). That is, authors can submit new conference is to provide the IR community with a only one paper. venue for presenting innovative search systems archi- There are four kinds of contributions: tectures and a publication opportunity. DESIRES does not compete with the established conferences presenting Full papers Papers usually lack rigorous frameworks, rigorous treatises in established areas; instead its goal is simulations of performance, or prototype imple- to air radically new ideas. mentations but present a radical departure from DESIRES mainly encourages papers about innovative conventional approaches that enable new appli- and risky information access and retrieval system ideas, cations. systems-building experience and insight, resourceful ex- Prototypes The prototype descriptions generally are a perimental studies, provocative position statements, new detailed report on successes and mistakes. application domains. DESIRES also welcomes contri- butions focusing on implementation details, successful Abstracts Ideas that are too half-baked for a paper or or failed reproducibility attempts, technological break- demo proposal are good candidates for an ab- throughs, and new uses of old ideas. stract. Traditionally, program committees in our IR field re- ward scholarship on narrow ideas, operate by consen- Open Problems in IR This is a new track. We are look- sus, discard “loosey-goosey” papers, including half-baked ing for abstract-like papers framing an important ideas and submissions that resemble war stories from the but unsolved problem in IR. "Open-Problems" pa- field. The major IR conferences usually reject such sub- pers are expected to have a single author. Any missions because they are not scientific. However, these author of a paper, prototype demo, or abstract may additionally submit one "Open-Problems" DESIRES 2021 – 2nd International Conference on Design of paper. Experimental Search & Information REtrieval Systems, September 15–18, 2021, Padua, Italy Originally, DESIRES were designed to run every other " oralonso@gmail.com (O. Alonso); marc@najork.org year in a retreat-like fashion (around the time of the Eu- (M. Najork); gianmaria.silvello@unipd.it (G. Silvello) ropean Summer School in Information Retrieval (ESSIR)); ~ https://www.linkedin.com/in/omar-alonso-8a5235/ (O. Alonso); ESSIR runs on odd years, DESIRES on even years. https://research.google/people/MarcNajork/ (M. Najork); The first edition took place in 2018 in Bertinoro (Italy), http://www.dei.unipd.it/~silvello/ (G. Silvello)  0000-0003-4970-4554 (G. Silvello) but due to the COVID-19 pandemic, DESIRES 2020, ini- © 2021 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0). tially planned in Venice (Italy), has to be postponed to CEUR Workshop Proceedings http://ceur-ws.org ISSN 1613-0073 CEUR Workshop Proceedings (CEUR-WS.org) Padua (Italy) in 2021. Forward to the Proceedings Advisory board members have been selected amongst the top senior members of the IR community seeking for These proceedings contain the papers selected for pre- balance between industry and academia. We thanks the sentation at the Second International Conference on De- advisory board members for their work and contribution sign of Experimental Search & Information REtrieval Sys- to the conference. tems (DESIRES 2021). 1 The conference was held from We thank all Program Committee members for their September 15 to September 18, 2021 at the Department time and effort in ensuring the high quality of the DE- of Information Engineering of the University of Padua 2 . SIRES 2018 program. DESIRES 2021 received a total of 38 submissions in two broad categories: 22 full papers and 16 short papers (abstracts, prototypes and open problems). General Chairs All the papers were reviewed by at least two mem- Omar Alonso, Instacart, USA Marc Najork, Google, USA bers of an international Program Committee formed by Gianmaria Silvello, University of Padua, Italy experts from industry and academia. Of the papers sub- mitted to the conference, 18 full papers and 10 short Advisory Board papers were accepted for oral presentation. The accepted contributions represent the state of the art in information Maristella Agosti, University of Padua, Italy retrieval, cover a diverse range of topics that we orga- Ricardo Baeza-Yates, Northeastern University, USA; UPF, nized in six main tracks: systems, search domains and Spain; Univ. de Chile applications, explorative search and querying, conver- Bruce Croft, University of Massachusetts, USA sational search, search and user-generated content and J. Shane Culpepper, RMIT University, Australia neural models. Susan Dumais, Microsoft, USA There were 58 unique authors with papers accepted Norbert Fuhr, University of Duisburg-Essen, Germany at DESIRES 2021 with the following geographical distri- Donna Harman, NIST, USA bution (affiliation): 15 authors from the USA (25.9%), 10 Kalervo Järvelin, University of Tampere, Finland from Germany (17.2%), 6 from The Netherlands (10.3%), Jan Pedersen, Walmart Labs, USA 5 from Austria, Canada, and Italy (8.6% each), 2 from Gerhard Weikum, MPI, Germany Belgium, Japan, Norway and Switzerland (3.4% each), and 1 from Australia, Denmark, France, Portugal and the Program Committee United Kingdom (1.7% each). There are three keynotes: Dyaa Albakour, Signal AI, UK James Allan, University of Massachusetts, USA • Apple Media Products Search, Brian Johnson, Ap- Krisztian Balog, University of Stavanger, Norway ple, USA. Alessandro Benedetti, Sease Ltd., UK • Humans Learn From Task Descriptions and So Barla Cambazoglu, RMIT University, Australia Should Our Models, Hinrich Schütze, University Diego Ceccarelli, Bloomberg, UK of Munich, Germany. Nick Craswell, Microsoft, USA • A hitchhiker’s guide to Ontology, Fabian M. Jeffrey Dalton, University of Glasgow, UK Suchanek, Télécom Paris University, Paris, Parth Gupta, Amazon, USA France. Claudia Hauff, Delft University of Technology, The DESIRES 2021 has been held under the patronage of the Netherlands Department of Information Engineering of the University Nicola Ferro, University of Padua, Italy of Padua and the University of Padua. Vasileios Kandylas, Microsoft, USA Finally, DESIRES 2021 would have not been possible Evangelos Kanoulas, University of Amsterdam, The without the financial support from the ExaMode H2020 Netherlands EU project (gold sponsor), Bloomberg and Google (sil- Jussi Karlgren, Gavagai & KTH, Sweden ver sponsors) and the Padova Convention and Visitors Emre Kiciman, Microsoft, USA Bureau (bronze sponsor). Matt Lease, The University of Texas at Austin, USA Craig Macdonald, University of Glasgow, UK Maria Maistro, University of Copenhagen, Denmark Organization Edgar Meij, Bloomberg, UK DESIRES has been conceived by the general chairs with Donald Metzler, Google, USA the support and suggestions of the advisory board. Yashar Moshfeghi, University of Strathclyde, UK 1 Jeremy Pickens, OpenText, USA http://desires.dei.unipd.it/ 2 Paolo Rosso, University of Valencia, Spain https://www.unipd.it/en/ Tony Russell-Rose, 2dSearch, UK Ian Soboroff, NIST, USA Damiano Spina, RMIT University, Australia Paul Thomas, Microsoft, USA University of Otago, New Zealand Olivier Van Laere, Apple Inc., USA Arjen de Vries, Radboud University, The Netherlands Hamed Zamani, University of Massachusetts Amherst, USA Local Organization Chair Dennis Dosso, University of Padua, Italy Proceedings Chair Stefano Marchesin, University of Padua, Italy