Title: Knowledge Extraction and Taxonomization from the Web Speaker: Zornitsa Kozareva (USC Information Sciences Institute) Time: 11am-12:15pm, May 9, Thursday Place: Science Center, room 4102, CUNY Graduate Center. 5th Ave & 34th St. Abstract: Knowledge extraction and taxonomization have been of great interest to the research community for a long time. With the development of technologies like Siri and IBM Watson, we have realized that existing knowledge bases are essential to make such applications work, but often the knowledge present in existing repositories is insufficient. This raised the question on how could one automatically build repositories containing not only high-level information such as found in Wikipedia, but also particular facts such as "Who appeared in a concert in the Hollywood Bowl last night?" or "What causes tumors to shrink?". This is a challenging problem, which was never solved despite many have worked on it. This talk will discuss recent methods for information gathering, sifting and organization that can rapidly, accurately and completely cover any area of interest mining unstructured texts on the Web. More concretely, the talk will cover topics on semantic class, instance and relation learning; taxonomization; graph-based reranking and label propagation. The talk will also touch upon natural language applications, which use the extracted knowledge. Short Bio: Dr. Zornitsa Kozareva is a Research Assistant Professor at the University of Southern California and a Research Scientist in the Natural Language group at the Information Sciences Institute. She received her PhD with Cum Laude from the University of Alicante, Spain. Her research interests lie in Web-based knowledge acquisition, text mining, lexical semantics, ontology population and multilingual information extraction. Zornitsa has co-organized four SemEval scientific challenges and workshops on topics like paraphrases, sentiment analysis, causality detection and relation identification. She was the leader of the team that won the answer validation challenge (AVE-2006) for French and Italian, and a member of the team that won the Spanish Geographic Information Retrieval (GeoClef-2006) challenge.