Negotiations Over Time in a Multi-Agent Environment: Preliminary Report

One of the major foci of research in distributed artificial intelligence (DAI) is the design of automated agents which can interact effectively in order to cooperate in problem-solving. Negotiation is recognized as an important means by which inter-agent cooperation is achieved. In this paper we suggest a strategic model of negotiation for N agents (N > 3), that takes the passage of time during the negotiation process itself into consideration. Changes in the agent's preferences over time will change their strategies in the negotiation and, as a result, the agreements they are willing to reach. We will show that in this model the delay in reaching such agreements can be shortened and in some cases avoided altogether. 1 Introduction One of the major foci of research in distributed artificial intelligence (DAI) is the design of automated agents which can interact effectively in order to cooperate in problem-solving. Negotiation is recognized as an important means by which inter-agent cooperation is achieved. That is, DAI is concerned with the design of agents which are able to communicate in such a way as to enhance the possibility of reaching mutually beneficial agreements concerning problems such as a division of labor or resources among the agents. Negotiation has always been a central theme in DAI This research has focused on strategies for designing agents capable of reaching mutually beneficial agreements. Sycara ([Sycara, 1987]), using case-based reasoning , and Kraus et al. ([Kraus et al., 1991J) modeled negotiations from a cognitive standpoint. Yet it is also recognized that although negotiations are necessary for reaching such agreements, the negotiation process is both costly and time-consuming, and thus may increase the overhead of the operation in question (see [Bond and Gasser, 1988]). In negotiations on such issues as job-sharing or resource allocation, it is important to minimize the amount of time spent on negotiating mutually beneficial agreements so as not to detract from time spent on the task itself. Thus, in the presence of time constraints, negotiation time should be taken into consideration. In [Kraus and Wilkenfeld, 1991a] we propose a strategic model of negotiation that takes the passage of time during the negotiation process itself into consideration. That study focused exclusively on a two-agent model. The present study generalizes this process by considering the N-agent environment. Kraus and Wilkenfeld, 1991a] we examine negotiation using game theory techniques with appropriate modifications to fit artificial intelligence situations. We …