Abstract
In the conventional cooperative games, it is assumed that the payoff of each coalition is known. However, in the real world problems, there may exist situations in which some coalitional values are unknown. In this paper, we investigate the theory of cooperative games under incomplete information of coalitional values. Assuming the superadditivity, we propose some concepts related to cooperative games under incomplete information. We investigate the solution concepts in a special case when only values of the grand coalition and singleton coalitions are known and show that there exists a focal point solution which is commonly suggested in many points of view.
