Negotiation and Conflict Resolution in Non-Cooperative Domains

Abstract

In previous work [Zlotkin and Rosenschein, 1989a], we have developed a negotiation protocol and offered some negotiation strategies that are in equilibrium. This negotiation process can be used only when the “negotiation set ” (NS) is not empty. Domains in which the negotiation sets are never empty are called cooperative domains; in general non-cooperative domains, the negotiation set is sometimes empty. In this paper, we present a theoretical negotiation model for rational agents in general noncooper at ive domains. Necessary and sufficient conditions for cooperation are outlined. By redefining the concept of utility, we are able to enlarge the number of situations that have a cooperative solution. An approach is offered for conflict resolution, and it is shown that even in a conflict situation, partial cooperative steps can be taken by interacting agents (that is, agents in fundamental conflict might still agree to cooperate up to a certain point). A Unified Negotiation Protocol is developed that can be used in all cases. It is shown that in certain borderline cooperative situations, a partial cooperative agreement (i.e., one that does not achieve all agents ’ goals) might be preferred by all agents, even though there exists a rational agreement that would achieve all their goals. compromise to reach mutually beneficial agreements. The work described in this paper follows the general direction of [Rosenschein and Genesereth, 1985; Zlotkin and Rosenschein, 1989a] in treating negotiation in the spirit of game theory, while altering game theory assumptions that are irrelevant to DAI. Previous work [Zlotkin and Rosenschein, 1989a] discussed inter-agent negotiation protocols and negotiation strategies that were in equilibrium, but could only be used if the s-called “negotiation set ” [Harsanyi, 19771 was not empty. Cooperative domains are those in which NS is never empty; in this paper, we present a theoretical negotiation model for general non-cooperative domains (where NS might be empty).