On how agents make friends: mechanisms for Trust Acquisition

1
On how agents make friends mechanisms for Trust
Acquisition

• Babak Esfandiari Sanjay Chandrasekharan
• Carleton University

2
Motivation

• Theoretical
• most current work on Trust is descriptive and
  non-constructive
• lack of emphasis on dynamic aspects of Trust such
  as Trust Acquisition and update
• Practical
• trust acquisition can accelerate multi-agent
  learning, and cooperation in general
• application in e-commerce, network management,
  RoboCup

3
Definitions

• Trust is a relation between two agents
• T A x A -gt 0,1
• ex T(jules, jim) 0.8 jules trusts jim 80
• Trust Acquisition is the process or mechanism
  that allows the calculation and update of T.

4
Trust Acquisition by Observation

• Bayesian model T(John, Mary) P(MTS)

S
P(MT) P(MF)
T F
70 30 10 90
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Trust Acquisition by Interaction

• Exploratory protocol
• Query protocol
• Maes
• Trust(wendy, lisa) wendy.evaluate(lisa,
  replies)

6
Institutionalizing Trust

• Institutions as a Brooksian way to reduce
  cognitive load
• Trust(bill, institution) 1
• Learning prejudice (!) through induction

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Trust Propagation(les amis de nos amis sont nos
amis)

• Social Network Analysis perspective
• Trust(A,C) ? Trust(A,B) x Trust(B,C)
• multiple paths
• cycles
• task-specific trust
• min_trust, max_trust
• (of all paths with no cycle)
• possible coloring of the edges

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Conclusion

• List of trust acquisition mechanisms
• Next application to RoboCup, e-commerce and
  network management