Report on the 2017 ACM SIGIR International Conference Theory of Information Retrieval (ICTIR?17)

This is a report on ICTIR'17, which continued its tradition of being the premier forum for presentation of research on theoretical aspects of Information Retrieval (IR). This includes theory in a broad sense, including conceptual papers that explore key concepts, theoretical papers that model concepts and/or relations between concepts, and papers that study theory in experimental or industrial settings. The importance of information access and information processing in industry and academia is growing in a revolutionary way, making the discussion on fundamental and long term aspects, and their relation to short term success and failure, more urgent than ever before. To highlight the increasingly strong connections between Information Retrieval and its neighboring disciplines, ICTIR'17 explicitly welcomed papers in IR areas that overlap with Human Information Access, Machine Learning, Natural Language Processing and Perception. ICTIR'17 in Amsterdam was a memorable conference. For those who like numbers: we had 142 attendees (biggest ICTIR ever), and 97 submissions with 52 accepted (largest ICTIR ever), 450/250 euro registration for everything (cheapest ICTIR ever), and for the first time in history the organization and keynotes of a leading IR conference where majority female (but selected for being outstanding researchers, of course).