TIME: 1:30-2:20 pm, May 29, 2007 PLACE: CSE 403 SPEAKER: Shang-Hua Teng Boston University TITLE: Game and Market Equilibria ABSTRACT: I will present some recent advances in algorithmic game theory especally about Nash equilibria. As you may have already known, the notion of Nash equilibria has captured the imagination of much of the computer science theory community, both for its many applications in the growing domain of online interactions and for its deep and fundamental mathematical structures. As the complexity and scale of typical internet applications increase, the problem of efficiently analyzing their game-theoretic properties becomes more pointed. In particular, I will cover the recent results in settling several open questions about Nash equilibria with focus on the approximation and smoothed complexity of non-cooperative two-player games. Those results link the computational complexity of Nash equilibria to Brower's fixed point, Sperner's lemma, and to Papadimitriou's complexity class, PPAD, characterized by the end-of-line problem. If time permits, I will also cover the extensions of these results to other equilibrium problems such as in trading and market economies. Joint work with Xi Chen (Tsinghua University), Xiaotie Deng (City University of Hong Kong). Also with Li-Sha Huang (Tsinghua University) and Paul Valiant (MIT).