演講者簡介 : Zaifu Yang got his Ph.D. in Economics from Tilburg University in 1996. He is currently serving as Professor of Faculty of Business Administration at Yokohama National University. His research interest is in microeconomics, game theory and management science.
演講摘要 : We study a competitive market model of trading in commodities that are all inherently indivisible, like houses and cars. Each agent is initially endowed with a bundle of goods and may consume several units of each good and has general preferences over the goods. Agents wish to swap their goods with each other in an effort to maximize their own welfare. We establish three major theorems stating general conditions under which a competitive equilibrium exists in this market. Our results subsume as special cases three important markets in the literature: 1) the well-known house allocation market of Shapley and Scarf (1974) satisfies our general condition and thus possesses an equilibrium; 2) if every agent views all goods in the market as substitutes in the sense of Kelso and Crawford (1982), then the market also has an equilibrium; and 3) if all items in the market can be split into two sets such that every agent regards items in the same set as substitutes but items across the two sets as complements, then the market has an equilibrium as well.
