C-IPS: Specifying Decision Interdependencies in Negotiations

Negotiation is an important mechanism of coordination in multiagent systems. Contrary to early conceptualizations of negotiating agents, we believe that decisions regarding the negotiation issue and the negotiation partner are equally important as the selection of negotiation steps. Our C-IPS approach considers these three aspects as separate de- cision processes. It requires an explicit specification of interdependencies between them. In this article we address the task of specifying the dy- namic interdependencies by means of IPS dynamics. Thereby we intro- duce a new level of modeling negotiating agents that is above negotiation mechanism and protocol design. IPS dynamics are presented using state charts. We define some generally required states, predicates and actions. We illustrate the dynamics by a simple example. The example is first specified for an idealized scenario and is then extended to a more realis- tic model that captures some features of open multiagent systems. The well-structured reasoning process for negotiating agents enables more comprehensive and hence more flexible architectures. The explicit mod- eling of all involved decisions and dependencies eases the understanding, evaluation, and comparison of different approaches to negotiating agents.