Invited Talks

Ian Horrocks, Oxford University, UK OWL: a Reasonable Ontology Language? Tuesday, 17th August, 2010, 18h30 (3.2.14)
The design of OWL was heavily influenced by description logics. One motivation for this was to enable the use of description logic inspired reasoning systems in OWL applications. In the more than six years since the publication of the standard, OWL has become a mainstream technology that is supported by major technology vendors and has been deployed in a wide range of applications. In this talk I will review our experience with OWL, consider the extent to which it has satisfied application requirements, and in particular examine both the usefulness and feasibility of OWL reasoning in practice. Short Bio Ian Horrocks is a Professor in the Oxford University Computing Laboratory where he jointly (with Georg Gottlob) leads the Information Systems Group. His research interests include description logics, ontology languages, and reasoning systems. He was centrally involved in the development of the OIL, DAML+OIL and OWL ontology languages, and was co-chair of the W3C Working Group that recently developed OWL 2. He also developed algorithms and implementation techniques that are employed in many reasoning systems. He has published more than 150 articles in conferences, journals and books. He is a BCS Fellow, an ECCAI Fellow, an EPSRC Senior Research Fellow and a past winner of the BCS Roger Needham award.
Manuela Veloso, CMU, USA Autonomous Mobile Robots Coexisting with Humans in Indoor Environments Wednesday, 18th August, 2010, 9h00 (3.2.14)
We envision ubiquitous autonomous mobile robots that can help and coexist with humans. Such robots are still far from common, as our environments offer great challenges to robust robot perception, cognition, and action. We realize the envisioned robot and human coexistance as offering a symbiotic human-robot interaction, such that we view robots and humans with complementary limitations and expertise. I will present CoBot, our visitor's companion robot that can provide guidance to visitors unfamiliar with the building, while it can also identify and overcome its limitations by asking for human help. I will present CoBot's effective mobile robot indoor localization and navigation algorithms that use a WiFi signature perceptual map combined with geometric constraints of the building. I will illustrate CoBot's performance with examples of a few autonomous hours-long past runs of the robot in Wean Hall and very recent runs in the new Gates Hillman Center. I will then discuss the opportunities and tradeoffs raised by the symbiotic human- robot interaction, and present illustrative studies. I conclude with the presentation of our second CoBot robot and the presentation of our ongoing work towards having multiple robots and humans engaged in planning and coordination for a variety of tasks. Short Bio Manuela M. Veloso is Herbert A. Simon Professor of Computer Science at Carnegie Mellon University. She directs the CORA L research laboratory, for the study of agents that Collaborate, Observe, Reason, Act, and Learn, www.cs.cmu.edu/~coral. Professor Veloso is a Fellow of the Association for the Advancement of Artificial Intelligence, and the President of the RoboCup Federation. She recently received the 2009 ACM/SIGART Autonomous Agents Research Award for her contributions to agents in uncertain and dynamic environments, including distributed robot localization and world modeling, strategy selection in multiagent systems in the presence of adversaries, and robot learning from demonstration. Professor Veloso is the author of one book on “Planning by Analogical Reasoning” and editor of several other books. She is also an author in over 200 journal articles and conference papers.
Judea Pearl, UCLA, USA The Logic of Causes and Counterfactuals Thursday, 19th August, 2010, 9h00 (3.2.14)
I will present a few basic principles and simple mathematical tools that are sufficient for solving most (if not all) problems involving causal and counterfactual relationships. The principles are based on non-parametric structural equation models, a natural generalization of those used by econometricians in the 1950-60s, yet cast in new mathematical underpinnings. This semantical framework, enriched with a few ideas from logic and graph theory, gives rise to a formal yet friendly calculus of counterfactuals that unifies all existing approaches to causation and resolves long-standing problems in several of the sciences. These include questions of confounding, causal effect estimation, policy analysis, legal responsibility, retrospective analysis, effect decomposition (mediation), instrumental variables, and the integration of data from diverse studies. Reference: J. Pearl, Causality (Cambridge University Press, 2nd ed. 2009) http://bayes.cs.ucla. edu/jp_home.html http://bayes.cs.ucla. edu/IJCAI 99 http://ftp.cs.ucla.edu/ pub/stat_ser/r350.pdf Short Bio Judea Pearl is a professor of computer science and statistics at the University of California, Los Angeles. He is a graduate of the Technion, Israel Institute of Technology, and has joined the faculty of UCLA in 1970, where he currently directs the Cognitive Systems Laboratory and conducts research in artificial intelligence, causal inference and philosophy of science. He has authored three books: Heuristics (1984), Probabilistic Reasoning (1988), and Causality (2000). A member of the National Academy of Engineering, and a Founding Fellow the American Association for Artificial Intelligence (AAAI ), Judea Pearl is the recipient of the IJCAI Research Excellence Award for 1999, the London School of Economics Lakatos Award for 2001 and the ACM Alan Newell Award for 2004. In 2008, he received the Benjamin Franklin Medal for Computer and Cognitive Science from the Franklin Institute.
Christos Papadimitriou, UC Berkeley, USA Computing Nash equilibria: The plot thickens Friday, 20th August, 2010, 9h00 (3.2.14)
Roger Myerson argued in 1999 that the Nash equilibrium lies at the foundations of modern economic thought. Seven years later, it was proven (by Daskalakis, Goldberg, and the speaker) that the concept's universality, famously established by Nash in 1950, is problematic, in that the problem of finding a Nash equilibrium is computationally intractable. Since then many more aspects of Nash equilibria in games and markets have been explored from the complexity standpoint, and the dark computational side of the concept keeps getting gloomier. We review several recent results establishing that playing repeated games, or playing games under considerations of risk, or disambiguating games via equilibrium selection a`-la Harsanyi- Selten, or computing equilibria by the homotopy method, are all rife with more and more serious complexity impediments. Short Bio Christos H. Papadimitriou is C. Lester Hogan Professor of Computer Science at UC Berkeley. Before joining Berkeley in 1996 he taught at Harvard, MIT , Athens Polytechnic, Stanford, and UCSD. He has written five textbooks and many research articles on algorithms and complexity, and their applications to optimization, databases, AI , economics, and the Internet. He holds a PhD from Princeton, and honorary doctorates from ETH (Zurich), the University of Macedonia, the University of Athens, and the University of Cyprus. He is a member of the American Academy of Arts and Sciences and of the National Academy of Engineering, and the National Academy of Sciences of the USA, and a fellow of the ACM. His novel Turing was published by MIT Press in 2003, and his graphic novel Logicomix (with Apostolos Doxiadis) by Bloomsbury in 2008.