Alma Mater Studiorum · Università di Bologna DOTTORATO DI RICERCA IN Culture Letterarie e Filologiche Ciclo XXXI Settore Concorsuale: 11/A4 (primario); 01/B1 (secondario) Settore Scientifico Disciplinare: M-STO/08 Mining Authoritativeness in Art Historical Photo Archives. Semantic Web Applications for Connoisseurship Presentata da: Marilena Daquino Coordinatore Dottorato: Supervisore: Prof. Luciano Formisano Prof.ssa Francesca Tomasi Esame finale anno 2019 Abstract The purpose of this work is threefold: (i) to facilitate knowledge discovery in art historical photo archives, (ii) to support users’ decision-making process when evaluating contradictory artwork attributions, and (iii) to provide policies for information quality improvement in art historical photo archives. The ap- proach is to leverage Semantic Web technologies in order to aggregate, assess, and recommend the most documented authorship attributions. In particular, findings of this work offer art historians an aid forre- trieving relevant sources, assessing textual authoritativeness (i.e. internal grounds) of sources of attribution, and evaluating cognitive authoritativeness of cited scholars. At the same time, the retrieval process allows art historical data providers to define a low-cost data integration process to update and enrich their collection data. The contributions of this thesis are the following: (1) a methodology for representing question- able information by means of ontologies; (2) a conceptual framework of Information Quality measures addressing dimensions of textual and cognitive authoritativeness characterising art historical data, (3) a number of policies for metadata quality improvement in art historical photo archives as derived from the application of the framework, (4) a ranking model leveraging the conceptual framework, (5) a semantic crawler, called mAuth, that harvests authorship attributions in the Web of Data, and (6) an API and a Web Application to serve information to applications and final users for consuming data. Despite findings are limited to a restricted number of photo archives and datasets, the research impacts on a broader number of stakeholders, such as archives, museums, and libraries, which can reuse the conceptual framework for assessing questionable information, mutatis mutandi, to other near fields in the Humanities. Keywords: Knowledge Discovery, Linked Data, Art History, Photography, Authoritativeness, Informa- tion Quality i ii Acknowledgements This work comes at the end of hard times. Personal events and work experiences affected significantly the result - sometimes in unpleasant ways, but mostly in unexpected, joyful, and exciting ways! First, I would like to express my gratitude to my supervisor Francesca Tomasi for the continuous support of my Ph.D study and related research. She supported me when I doubted of my skills, she made me understand what I am able to do, and to feel comfortable with my limits. She gave me all the strength I needed to focus on my objectives and free my creativity. She was with me when I was ill, when I felt alone, and she made me feel at home when I felt I had no home to go back. For such reasons, I want to thank her for being a friend, not an advisor only. Secondly, I would like to thank Francesca Mambelli from the Federico Zeri Foundation. I cannot imagine this thesis without her doubts and insightful questions. She helped me to understand what an incredible work is under the hood of cultural heritage management and how fascinating it could be. In the last few years I met an incredible amount of brilliant people thanks to my job. By attending events organised by the Semantic Web community and by discussing with PHAROS members I got precious feedback and I learnt, almost from scratch, all I needed to write this thesis. I want to thank all of them for supporting me in the evaluation of this work and for contributing to the knowledge I gained, which is priceless. Among them, a special thanks goes to my two reviewers, Enrico Daga (KMI) and Costanza Caraffa (KHI), whose comments helped me to frame questions related to so different communities - which are (hopefully) highlighted in this work. In particular, thanks to Enrico for his patience when explaining me how not to write a PhD thesis and how not to be concerned (too much) of it. Workshops, conferences, and summer schools have been fantastic places for networking. At SSSW2016 I met few of the people that keep positively affecting my career and that are now some of my best friends. There I met for the first time the KMI crew, who managed to make me move (twice) to the exotic Milton Keynes. A special thanks goes to Mathieu d’A., Alessandro Adamou, Enrico Daga (again), and Enrico Motta, for supporting and guiding me during my visiting period. The MK experience was unique, not only in working terms. The impressive number of good people that concentrate insucha small place is unspeakable. I cannot list all of them, but I can mention the ones that still walk with me despite the long distance: Ilaria, my beloved grumpy friend, that never makes me feel alone; Pinelopi, with whom I shared fears, ideas and lots of hugs during our cigarette breaks; Martin, who took care of me as only a brother would do; Tina, for pushing me all the time to challenge myself and make the best of situations; Angelo iii and Andrea, for their friendship and kindness when helping me coding; Manu and Giorgio for their good advices, and the silly moments together (that are hard to distinguish sometimes); and (in random order) Carla, Davide, Paco, Anna, Anita, Francesco, Thivian, Vasa, Patrizia, Jaisha, Julian, Matteo, and all the others, for all the fun we had together. Another group of people influenced my career, that is, the AlmaDL division at the University of Bologna, where I spent three years as research assistant. I want to thank Raffaele, Marialaura, Roberta, Piero, Jen- nifer, Fabrizio, and Antonio, with whom I moved my first steps in research. And of course I thank pro- fessors, colleagues and the admin team at the Department of Classic Philology and Italian Studies that continuously help me, including: Federico Condello, Paola Italia, Aldo Gangemi, Ivan Heibi, Alessan- dra Di Tella, Beatrice Nava, Morena, Laura, Virna, Valeria, and Antonella; Valentina Presutti, Mehewish Alam, Valentina Carriero, Andrea Nuzzolese (STLab - CNR); Fabio Vitali, and Angelo Di Iorio (DISI). Lastly, thanks to Silvio Peroni, my panino-buddy and a good advisor since I started this adventure. I have been living in Bologna for almost fourteen years. Plenty of people crossed my path. Some moved away, some stayed for longer, and some keep bringing joy in my life every day. Among them are Giulia, my beautiful dreamer; Martina, as adventurous as cloudy; Maria Rosaria, the tiny crazy traveller; Andrea, the brilliant grumpy friend (who will raise his eyebrows when reading it); Daniel, the worst proofreader ever, but a thoughtful friend; Matteo and his family (Nadia, Vanni, Fazia, and Danilo), who were like a second family to me; Raffaele (again), for the litres of beer we poured while chit-chatting in all thepubs and restaurants of Bologna; Roberta, possibly the craziest flatmate I have ever had, with the biggest heart I could expect. And of course, I must mention my hometown. Domodossola became famous thanks to The Fortune wheel TV program, where it was first used to spell words that start with D. Now everybody ask me “Does itexist for real?”. Spoiler alert: it does, it is beautiful, and amazing people live there. My pieces of heart Simone and Federico; Gabriele (Teddy), smart and sensitive; Veronika, a friend and the best sister-in-law I could ask for. My siblings Miriam and Marco, my biggest treasure. My mother, who deserves all the best in this world. My cousins Lorella, Beppe, Alessia, my uncles and aunts, with whom I shared the best moments. And my beautiful niece Marika, who makes us smile again. Lastly, I want to remember my grandparents, that keep looking down on us, and my father, who taught me to love science, photography, arts, and to be curious. I owe him everything. This work is dedicated to him. iv To whom will not read this thesis, but that gave me all the love I needed to make it happen. v vi Introduction Art historical photo archives have always been places for art historical research. Scholars, photographers, art dealers, antiquarians, and others, used to create, arrange, and study photographic collections depicting artworks in order to pursue their activities. Plenty of connoisseurs, i.e. experts that ascribe artworks to artists on the basis of their knowledge in the field of fine arts, used to attend photo archives and torecord on the back of photographs their hypotheses. The latter include expertises on the authorship of artworks, provenance information of artworks, and bibliographic references. The wealth preserved in photo archives bears witness to the diversity of scientific methods that characterised connoisseurship in the last two centuries. According to Carlo Ginzburg [Ginzburg, 1979] the epistemo- logical model in the Humanities that emerged in the nineteenth century stems from connoisseurship. To this extent, characteristics of connoisseurs’ methodologies are of great interest to other fields in the Hu- manities. However, most of connoisseurs’ methodologies are not reproducible, and authoritativeness of scholars and sources is a key element when validating attributions. This work is mainly devoted to understand how connoisseurs’ methodologies sedimented in photo archives, to what extent we can formalize a definition of authoritativeness on the basis of second-hand knowledge providers, and to what extent such a definition can be leveraged in information technologies. In particular, a formal definition of authoritativeness would contribute to advancements of two research areas, namely: Connoisseurship, by developing more reliable recommending systems for scholars, and Library and Infor- mation Science, by defining new strategies for metadata quality improvement based on the aforementioned recommending systems.