Persuasion Based on Exchanging Proposals for Cooperative
Scheduling
Takayuki Ito and Toramatsu Shintani
Department of Intelligence and Computer Science, Nagoya Institute of Technology, Nagoya, Japan 466-8555
SUMMARY
Software agents, which can act autonomously and
cooperatively in network environments on behalf of their
users, are being actively investigated. Reaching a consensus
is one of the most important activities of agents. The coop-
eration of the agents in creating a global schedule (a sched-
ule being a vector of events), we call cooperative
scheduling. In this article, we formalize cooperative
scheduling as a bargaining problem in game theory, then
we propose a persuasion method for solving the bargaining
problem among agents. We propose a persuasion method
based on exchanging proposals between agents. Namely,
each agent receives the others proposal in compensation
for the others acceptance of his own proposal. In our
experiments, we use agenda scheduling as an example of
cooperative scheduling and demonstrate the efficiency of
the persuasion method proposed here. ©1999 Scripta Tech-
nica, Syst Comp Jpn, 30(7): 18, 1999
Key words: Multi-agent systems; persuasion;
reaching a consensus; game theory; negotiation.
1. Introduction
In recent years, software agents [2, 7] have been
investigated very actively. These can act autonomously and
cooperatively in network environments on behalf of their
users. A multiagent system is a system in which multiple
agents autonomously and cooperatively solve local and
global problems. Reaching a consensus [10, 11, 17] is a
central issue for multiagent systems.
In this article, we assume a situation in which each
agent has a local schedule and tries to reach a consensus in
order to create a global schedule. The cooperation of the
agents in creating a global schedule (a schedule being a
vector of events) we call cooperative scheduling. For
example, when scheduling agendas for a meeting, each
agenda is an event. Each agent has individual preference for
a schedule. We call individual preferences local prefer-
ences. Local preferences should be reflected on a global
schedule. Here, we formalize a method for cooperative
scheduling. We then propose a persuasion method for cre-
ating a global schedule in which local preferences are
reflected.
In real society, there exist a variety of methods for
persuasion [8]. We have modeled some persuasion methods
and applied them to negotiation among software agents. In
a process of persuasion, an agent who persuades another
agent is called a persuader and an agent who is persuaded
by a persuader is called a compromiser. The outline of the
persuasion protocol can be shown as follows. (Request) the
persuader sends a proposal to the compromiser in order to
reach a consensus. (Compromise) the compromiser re-
ceives the proposal. If the compromiser is able to accept the
proposal, he (or she) need not revise his (or her) belief. If
he is unable to accept the proposal, the compromiser tries
to revise his belief (needs, decisions, or preference) in order
to accept the proposal. (Reply) as the result of the belief
revision, if the compromiser is able to accept the proposal,
he replies in the form of an agreement message. If not, the
compromiser replies by sending a reject message.
CCC0882-1666/99/070001-08
© 1999 Scripta Technica
Systems and Computers in Japan, Vol. 30, No. 7, 1999
Translated from Denshi Joho Tsushin Gakkai Ronbunshi, Vol. J81-D-I, No. 9, September 1998, pp. 10991106
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