1. Market-Driven Multi-Agent Collaboration in Robot Soccer Domain Presented by Barış Kurt

2. Outline What is a Market-Driven Strategy? How it works? Different Implementations

3. What is a Market-Driven Strategy? Application of the basic properties of free market economy to increase the benefit Based on the basic assumption that maximizing individual profits will approximate global profit maximization Used for multi-agent task allocation

4. How it works? There exists an overall goal of the team that an outside entity is assumed to offer a payoff The goal is decomposed into smaller tasks and an auction is performed for each of them For each task, agents offer their prices to the auctioneer The bidder with the lowest offered price will be given the right of execution of the task

5. Market-driven scenario

6. Prices of Tasks: The Cost Functions The prices that agents offer for tasks are the estimated costs for accomplishing that task For example: C attacker = M 2 *dist Ball + M 2 *dist OppGoal

7. Auction Mechanism In Cerberus 2005 if(playerNumber==minDistOwner&&playerNumber==minDistOwnerForOppGoal) { robotRole=RR_PRIMARY_DEFENDER; } else if(playerNumber==minDistOwner) { robotRole=RR_SECONDARY_ATTACKER; } else if(playerNumber==minDistOwnerForOppGoal) { robotRole=RR_SECONDARY_ATTACKER; } else if(playerNumber==minDistOwnerToOwnGoal) { robotRole=RR_PRIMARY_DEFENDER; } else { robotRole=RR_SECONDARY_ATTACKER; }

8. Different Implementations Centralized Distributed Hybrid?

9. Centralized Implementation There exists a master agent (auctioneer) that controls the auctions and assigns the roles. The master agent receives offers from all other agents for each task and sends the auction results back. Computationally efficient. Prone to single point failures.

10. Distributed Implementation No master agent. Every agent broadcasts its offer for every task. Every agent runs the same auction mechanism and parallely computes the auction results. Robust against single point failures Requires more computation in total.

11. Hybrid Implementation There exists a master agent There is also an auction for the task of being the master Robust against single point failures Computationly efficient Still not implemented, no test results.

12. Thanks.. Questions?