Partition-based Stability Concepts and a Partial Order that Links Risk Aversion to Cooperation

Workshop’s Topic: We are concerned with the stability of a coalition game, i.e. a cooperative game with transferable utility. For us, the stability of a state should refer to the difficulty of leaving it once it has been reached. Following this guideline, the concept of the core can be weakened so that the blocking of changes is limited only to those with multilateral support. This principle of consensual blocking, as well as the traditional core definition of unilateral blocking and intermediate blocking, can all be applied to partition-allocation pairs. Each of these pairs consists of a partition of the grand coalition and a corresponding allocation vector whose components are efficient and individually rational for the different constituent coalitions of the given partition. Of the resulting stability concepts, two are universal in the sense that every game, no matter how "bad" it is, has its share of stable solutions. For a game that has strictly positive values, the imputations would also have fractional interpretations. These would allow a particular ranking between the games, which we consider to be in the sense of "centripetality", to imply a clearly describable shift in the stable solutions of the games. If coalitions’ values are based both on random outcomes and on a common, positively homogeneous reward function that characterizes players’ gains from their shares, these comparative statics could explain why risk aversion often promotes cooperation.

Time and Location: 10:00-11:30 AM (GMT+8), Room A523 (School of Management)

Language: Bilingual (Chinese and English)

Introduction of Speakers

Dr. YANG Jian

Rutgers University, Rutgers Business School

Dr. Jian Yang received his Ph.D. in Management Science from the University of Texas at Austin. After working for the Department of Mechanical and Industrial Engineering at the New Jersey Institute of Technology, he is now a professor at the Department of Management Science and Information Systems, Rutgers Business School, Rutgers University. Dr. Yang’s research interests are in the areas of combinatorial optimization, logistics, production and inventory control, dynamic pricing, and game theory. Currently, he is particularly interested in the role of risk and ambiguity in dynamic inventory price control and in game-theoretic contexts.