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Automated negotiations. The best terms for all concerned Tuomas Sandholm [email protected]. Overview. Automated negotiations Promising application areas Reallocation among agents Optimization Agent-to-agent vs. centrally mediated eMediator: features. Automated negotiations. - PowerPoint PPT Presentation
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Institute for Visualization and Perception ResearchI VPR 1
© Copyright 1998 Haim Levkowitz
Automated negotiations
• The best terms for all concerned
• Tuomas Sandholm
Institute for Visualization and Perception ResearchI VPR 2
© Copyright 1998 Haim Levkowitz
Overview
• Automated negotiations
• Promising application areas
• Reallocation among agents
• Optimization
• Agent-to-agent vs. centrally mediated
• eMediator: features
Institute for Visualization and Perception ResearchI VPR 3
© Copyright 1998 Haim Levkowitz
Automated negotiations
• Negotiation: key component in e-commerce
• Auto: computational agents
• Represent real-world parties
• Find & prepare contracts
• Benefits …
Institute for Visualization and Perception ResearchI VPR 4
© Copyright 1998 Haim Levkowitz
Auto negotiation benefits
• Save human negotiation time
• Better at finding deals in combinatorially & strategically complex situations
• Not at cost to other parties
• Rapidly find solutions that optimize for all
Institute for Visualization and Perception ResearchI VPR 5
© Copyright 1998 Haim Levkowitz
Promising application areas
• Retail e-commerce
• Electricity markets
• Bandwidth allocation
• Manufacturing planning & scheduling in subcontracting networks
• Distributed vehicle routing among independent dispatch centers
• Electronic trading of financial instruments
Institute for Visualization and Perception ResearchI VPR 6
© Copyright 1998 Haim Levkowitz
Reallocation among agents
• Task reallocation among agents: key type of negotiation
• Allocate tasks to agents that handle them least expensively
• Marginal cost-based method for automated task reallocation
• Reallocate all types of items ….
Institute for Visualization and Perception ResearchI VPR 7
© Copyright 1998 Haim Levkowitz
Items to reallocate
• Tasks
• Financial instruments
• Hours of electricity
Institute for Visualization and Perception ResearchI VPR 8
© Copyright 1998 Haim Levkowitz
Cost-based reallocation
• Agent takes task from another as long as it is paid more by other agent than what costs to handle
• Agent gives task to another agent as long as it doesn’t have to pay more than it would cost to handle
• TRACONET: TRAnsportation Cooperation NET
Institute for Visualization and Perception ResearchI VPR 9
© Copyright 1998 Haim Levkowitz
TRACONET
• Automated delivery of task reallocation among freight companies
• 1st distributed automated negotiation among self-interested agents
• Each agent• Own Unix process• Represents single company
Institute for Visualization and Perception ResearchI VPR 10
© Copyright 1998 Haim Levkowitz
TRACONET (cont.)
• Agent takes on delivery tasks
• Gives out tasks
• Recontract-out tasks previously contracted-in
Institute for Visualization and Perception ResearchI VPR 11
© Copyright 1998 Haim Levkowitz
Optimization
• Negotiation can get stuck in local optimization
• Task allocation suboptimal
• No original contract (O) profitable
• To solve: new contract types …
Institute for Visualization and Perception ResearchI VPR 12
© Copyright 1998 Haim Levkowitz
New contract types
• C: cluster• Exchange multiple tasks for payment
• S: swap task for another + sidepayment• M: multiagent
• More than 2 parties in same contract• OCSM …
Institute for Visualization and Perception ResearchI VPR 13
© Copyright 1998 Haim Levkowitz
OCSM …
• Combine previous into atomic contract
• Guarantee globally optimal allocation
• Through finite number of contracts
Institute for Visualization and Perception ResearchI VPR 14
© Copyright 1998 Haim Levkowitz
Agent-to-agent vs. centrally mediated
• Original: agent-to-agent• Auction server ==> centrally mediated
variant• Agents send bids and tasks• ==> Combinatorial auctions
• Allow users to express interrelated valuations of items
Institute for Visualization and Perception ResearchI VPR 15
© Copyright 1998 Haim Levkowitz
eMediator: features
• E-commerce server
• Also services other than auctions
• Combinatorial bidding
• Bidding via price-quantity graphs
• Mobile agents
• Determine winners of combinatorial auction
• Identify profitable contacts for all
Institute for Visualization and Perception ResearchI VPR 16
© Copyright 1998 Haim Levkowitz
Optimal winner determination
• Computationally complex
• ==> Added highly optimized search-based matching algorithm to solve problem
Institute for Visualization and Perception ResearchI VPR 17
© Copyright 1998 Haim Levkowitz
Price-quantity graphs
• User can express continuous preferences
Institute for Visualization and Perception ResearchI VPR 18
© Copyright 1998 Haim Levkowitz
Mobile agents
• User have agents participate in auctions while users disconnected from Internet
• Mobile agents execute on agent dock on or near auction host
• ==> Reduce network latency
• Key issue in time-critical bidding
• Mitsubishi’s Concordia agent dock
Institute for Visualization and Perception ResearchI VPR 19
© Copyright 1998 Haim Levkowitz
Concordia
• Give mobile agents safe execution platform• Bid• Set up auctions• Travel to other auction sites• Observe activity at various auctions• More later
Institute for Visualization and Perception ResearchI VPR 20
© Copyright 1998 Haim Levkowitz
HTML interface
• Users instruct agents
• Automatic generation of Java code for mobile agents before launching
Institute for Visualization and Perception ResearchI VPR 21
© Copyright 1998 Haim Levkowitz
Contract management• Usually: binding
• ==> Can’t undo old commitments to accommodate new events• E.g., tasks more costly than anticipated• New offers more lucrative
• Alleviate: Leveled commitment contracting protocol …
Institute for Visualization and Perception ResearchI VPR 22
© Copyright 1998 Haim Levkowitz
Leveled commitment contracting protocol
• Agents accommodate future events
• Option of unilateral decommit
• Decommitment penalty