Stability regions for DISC when donors and observers may have different amount of information.

and are the probabilities that the donor and the observer know the recipient's reputation in a single game, respectively. If the benefit-to-cost ratio is smaller than the lower bound, is invaded by six action rules, i.e., all the other action rules except . If is larger than the upper bound, is invaded by . To prevent the invasion by the six action rules, donors must have sufficient information about recipients' reputations under all the social norms. To prevent the invasion by , observers must have sufficient information about recipients' reputations under suspicious social norms (Fig. 5(A), Fig. 5(C), and Fig. 5(G)). This is not the case under trustful social norms (Fig. 5(E)).