Comparing rankings of heterogeneous agents

A central problem in the study of autonomous cooperating systems is that of how to establish mechanisms for controlling the interactions between different parts (which are called agents) of the system. For heterogeneous agents this aims at, modeling the basics for their decisions. The mechanisms we discuss in this paper are based on the assumption that, the agents can estimate the effects of being attached to a certain set of goals. In the simplest case this is expressed by a single value e.g., the cost that will arise for the accomplishment of these goals. But in general this estimation may be arbitrarily complicated. In addition, we assume that, the agents have a function available to mnk their goals according to the estimated values and they pursue the goals they rank best. Then, these values can be used to resolve various kinds of conflicts in this kind of systems. For example in the task allocation phase the case of multiple applications for the allocation of a goal can be decided by allocating the goal to the agent with the ‘(best estimation”. Another way of using these values is for establishing collaborative actions between a pair (or a set) of agents: If one agent wants to get support in the accomplishment, of a particular goal he will try to persuade another agent to modify his ranking of the goal in such a way that, they both will rank best this “common” goal. Thus, the use of ranking functions provides a general framework for considering cooperative aspects within the study of multi-agent systems. An essential question in this context is how the rankings of different agents can be compared. Therefore, we develop in this paper a formalization of the concept, of ranking functions and discuss mechanisms that establish the comparability of different, rankings. *This work was supported by the German Ministry of Research and Technology under grant ITW9104 COOCS’93 -1 I1931CA, USA o 1993 ACM O-89791 -627 -1 19310010... $1 .50