Conférenciers Invités

Paul Goldberg, University of Liverpool

The Complexity of Computing a Nash Equilibrium

Résumé. Game theory is the study of mathematical models of strategic, non-cooperative interaction amongst selfish agents. For these mathematical models, one seeks solutions, which model the outcome of the game. In 1951, John Nash obtained his celebrated result that every game admits a - possibly randomised - solution, now known as Nash equilibrium in his honour. The proof of existence is non-constructive however, raising the question of how to compute a solution algorithmically, a question of considerable interest in the context of theoretical Computer Science, as well as Game Theory. In the talk, I will survey work by myself and others that has shed light on the computational complexity of this problem, by relating it to the computation of generic Brouwer fixpoints.

Biographie. Prof Paul Goldberg has been at the University of Liverpool for three years, where he currently leads a newly-formed research group on Economics and Computation. Prior to that, he taught at the University of Warwick, and was a researcher at Aston University and Sandia National Laboratories, New Mexico, USA. Prof Goldberg’s paper “The Complexity of Computing a Nash Equilibrium” co-authored with Christos Papadimitriou and Constantinos Daskalakis, was awarded the Game Theory and Computer Science Prize at the 3rd World Congress of the Game Theory Society, in July 2008. Prof. Goldberg has worked on various other aspects of algorithmic game theory, and prior to that, on computational learning theory.

Leon van der Torre, University of Luxembourg

Changing conditional norms

Résumé. AGM theory change was developed as a formal framework for norm change, but its restriction to propositional theories does not make it suitable for conditional norms. In this talk we discuss the relevance of norm change for formal models of interaction, and we present some results for change of conditional norms.

Biographie. Leon van der Torre obtained his PhD from the University of Rotterdam in 1997, with his PhD thesis entitled Reasoning about obligations: preferences in defeasible deontic logic. In 2006 he started as a full professor in intelligent systems at the University of Luxembourg, where he is responsible for strategic priority P1 on security and reliability of University of Luxembourg. On May 2nd, 2007, he gave his inaugural speech entitled “Violation games: a new approach of handling norms in intelligent systems.” He works on deontic logic, knowledge representation and multiagent systems. He developed the BOID agent architecture (with colleagues from Vrije Universiteit), the input/output logics (with David Makinson) and the game-theoretic approach to normative multiagent systems (with Guido Boella from University of Turin).

Philippe Palanque, University Paul Sabatier (Toulouse 3)

Défis pour les Approches Formelles pour l’Ingénierie des Systèmes Interactifs

Résumé. Cette présentation va faire un tour d’horizon et un historique de l’exploitation des approches formelles dans le domaine de l’Interaction Homme-Machine et plus particulièrement en ce qui concerne la conception, la construction et l’évaluation des systèmes interactifs. Seront ensuite présentés un ensemble de cas montrant l’utilisation effective de ces approches sur des problèmes particuliers en prenant comme champ d’application particulier les systèmes critiques tels que le contrôle aérien, les cockpits d’avions ou les segments sol de gestion de satellites. Nous montrerons en particulier comment la notation ICO et l’outil PetShop, développés au sein de l’équipe, ont été appliqués à ces différents domaines. Cette présentation conclura par l’identification d’un agenda de recherche et de problèmes restant à résoudre ainsi qu’une “roadmap” pour les travaux futurs.

Biographie. Dr. Philippe Palanque is a Professor in Computer Science at the University
Toulouse 3 - Paul Sabatier and is currently Head of the IHCS at IRIT. From 1995 he spent 2 years at DSNA/DTI/R&D(formally known as the CENA, the French Research Centre of Civil Aviation) to develop and apply formal specification and interactive system design techniques in the field of Air Traffic Control. For 4 years he has been involved in several research projects funded by the French Department of Defense dealing with notations and tools for the specification of real-time interactive systems and applied to cockpits of military aircrafts and drones. More recently, he is involved in developing tools and techniques (in the domain of civil aviation) for the specification and certification of new interactive cockpits (that have to be compliant with ARINC 661 specification standard) as the ones of large commercial aircrafts. He has been working on research projects to improve interactive Ground Segment Systems, funded by the French Space Agency (CNES) for 10 years, beginning in 2001. His current research interests deal with formal description techniques to support design and construction of resilient interactive systems considering in a balanced way usability, safety and dependability. e is chair of the IFIP Working group 13.5 on Human Error Safety and System Development and is adjunct chair for specialized conferences within ACM SIGCHI (Special Interest Group on Human-Computer Interaction). He edited and co-edited eight books or conference proceedings and co-authored more than 100 refereed publications in international conferences and journals.