A Report on the Ninth International Web Rule Symposium

2015) was held in Berlin, Germany, from August 2–5. The symposium was organized by Adrian Paschke (general chair), Fariba Sadri (program cochair), Nick Bassiliades (program cochair), and Georg Gottlob program cochair). A total number of 94 papers were submitted from which 22 full papers, 1 short paper, 2 keynote papers, 3 track papers, 4 tutorial papers, 6 industry papers, 6 challenge papers, 3 competition papers, 5 Ph.D. papers and 3 poster papers were selected. The papers were presented in multiple tracks on complex event processing, existential rules and Datalog+/–, industry applications, legal rules and reasoning, and rule learning. Following the precedent set in earlier years, RuleML also hosted the Fifth RuleML Doctoral Consortium and the Ninth International Rule Challenge as well as the RuleML Competition, which this year was dedicated to rule-based recommender systems on the web of data. A highlight of this year’s event was the industry track, which introduced six papers describing research work in innovative companies. New this year was also the joint RuleML / reasoning web tutorial day on the first day of the symposium, with four tutorials — TPTP World by Geoff Sutcliffe, PSOA RuleML by Harold Boley, Rulelog by Benjamin Grosof, and OASIS LegalRuleML by Tara Athan. Reports