Agent-Mediated Electronic Commerce. Designing Trading Strategies and Mechanisms for Electronic Markets [electronic resource] : AMEC 2011, Taipei, Taiwan, May 2, 2011, and TADA 2011, Barcelona, Spain, July 17, 2011, Revised Selected Papers / edited by Esther David, Valentin Robu, Onn Shehory, Sebastian Stein, Andreas Symeonidis.