Reasoning about Commitments and Penalties for
Coordination between Autonomous Agents
Cora B. Excelente-Toledo
University of Southampton
Dept. of Electronics and
Computer Science
Southampton SO17 1BJ, UK
cbet99r@ecs.soton.ac.uk
Rachel A. Bourne
Queen Mary
Univ. of London
Dept. of Elec. Eng.
London E1 4NS, UK
r.a.bourne@elec.qmw.ac.uk
Nicholas R. Jennings
University of Southampton
Dept. of Electronics and
Computer Science
Southampton SO17 1BJ, UK
nrj@ecs.soton.ac.uk
ABSTRACT
1. INTRODUCTION
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AGENTS’01,
May 28-June 1, 2001, Montr´eal, Quebec, Canada.
Copyright 2001 ACM 1-58113-326-X/01/0005 ...
+5.00.
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2. THE SCENARIO
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3. COMMITMENTS AND PENALTIES
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4. AGENT DECISION MAKING
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4.1 Deciding on the direction of movement
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4.2 Deciding which CM to select
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4.3 Deciding what to bid to become an AiCoop
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4.4 Deciding which AiCoop bids to accept
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4.5 Deciding how to set the penalty fee
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4.6 Deciding when to drop a commitment
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5. EXPERIMENTAL EVALUATION
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0
500
1000
1500
2000
2500
3000
Total
Partial (50%)
Loose
Level of Commitment
Tot
al reward obt
ained by all agent
s
0
200
400
600
800
1000
1200
1400
1600
Number of CTs achi
eved
AiC
AiCoop
AiS
CTs accomplished
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10
20
30
40
50
60
70
0%
25%
50%
75%
100%
Percentage of Commitment
Nu
m
ber
of
C
Ts decom
m
itt
ed
Unrecovered
Recovered
0
10
20
30
40
50
60
0%
25%
50%
75%
100%
Fixed Penalty with a percentage of the CT Reward
Number
of CTs decommitted
0
5000
10000
15000
20000
25000
Aver
age penalty fee
Recovered
Unrecovered
Penalty Fee
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5
10
15
20
25
30
35
40
0%
25%
50%
75%
100%
Level of Commitment
Nu
m
ber
of
C
Ts decom
m
itt
ed
0
100
200
300
400
500
600
700
800
900
Aver
age penal
ty f
ee
Recovered
Unrecovered
Penalty Fee
0
5
10
15
20
25
30
35
40
0%
25%
50%
75%
100%
Level of Commitment
Nu
mb
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f CT
s d
ec
ommi
tte
d
0
100
200
300
400
500
600
700
800
900
Average penalty fee
Recovered
Unrecovered
Penalty Fee
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0
500
1000
1500
2000
2500
3000
3500
Total Partial
(50%)
Loose
Level of Commitment
AiC Total reward
Sunk Cost
Partially Sanctioned
Penalty Fixed 50% CT
Penalty Fixed 0% CT
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6. RELATED WORK
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7. CONCLUSIONS
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8. ACKNOWLEDGMENTS
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9. REFERENCES
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