A Decentralized Model for Multi-attribute Negotiations

Abstract

This paper presents a decentralized model that allows self-interested agents to reach "win-win" agreements in a multi-attribute negotiation. The model is based on an alternating-offer protocol. In each period, the proposing agent is allowed to make a limited number of offers. The responding agent can choose the best offer or reject all of them. In the case of rejection, agents exchange their roles and the negotiation proceeds to the next period. To make counteroffers, an agent first uses the heuristic of choosing, on an indifference curve (or surface), the offer that is closest to the best offer made by the opponent in the previous period, and then taking this offer as the seed, chooses several other offers randomly in a specified neighborhood of this seed offer. Experimental results show that this model can make agents reach near Pareto optimal agreements in general situations where agents have complex preferences on the attributes and incomplete information. Moreover, different from other solutions for multi-attribute negotiations, this model does not require the presence of a mediator.