Agents

1. Agents • Computer Programs of a certain type • Effectively bodiless robots • Rise of internet enables Agents • Lostness • As life becomes more complex, we cannot keep up with it • We’re lost in over-complex world • Agents can perform work on our behalf

2. Autonomy • Agents are autonomous • Make own decisions • E.g. buying agent may decide when to purchase goods, and arrange for them to be delivered • Agents may need considerable intelligence so that they can make good decisions

3. Persistent Existence • Agents exist “over time” • Disk space compression agent may be running all the time our computer is on • Purchasing agents started running, may run for weeks while waiting for best price • Mobile agents may be running even when our computer is off • Return to ‘base’ at later time

4. Pro-Active • Agents decide themselves when to act, in pure form without impetus from user • Agents may act due to a number of triggers • user events • system events • changes in status • timed events • other agent events

5. Communicative • Agents able to communicate • Most interesting, communication between programs from different sources • E.g. buying agent for user X negotiating price with supplier agent for company Y • More generally, may communicate to solve problems • KQML - defined wrapper for messages

6. Economic Potential • Benefit from user’s point of view • Price comparison without wasting user’s time • Benefit for industry • Able to tap into growing Agent marketplace • Scale of agent-related commerce • $357million in 1998 • Est. $4.6billion in 2006

7. Blackboard System

8. Message Passing

9. Match-Making

10. Brokering

11. Static Agents • Remain in one place • E.g. user’s or remote computer • May communicate with outside world • E.g. TutorAgent • Remote Program Calls • Remote Method Invocation (Java) • Relatively few security problems

12. Mobile Agents • Agents themselves may move • E.g. Agent may leave your computer and visit computers of several airlines • Generally need way of packaging up code and transporting • Need machine/OS independent execution environment (Java, Telescript)

13. Security Problems with Mobile Agents • Danger to Machine • Rogue agents • Agents may attack machines they visit • Agents may carry digital signatures • Rogue hosts • Host may attack agent • E.g. change prices so that host appears cheapest

14. Agents and Information Search • Major application for agents search for information • E.g. tutoragent, searches for resources on web relevant to on-line lecture notes • Stanford Digital Library project • Uses commerce model for non-commercial application(!)

15. Agents and E-Commerce • Need Identification • Product brokering • Firefly • Merchant brokering • Bargainfinder • Negotiation • Kasbah • Product service

16. Recommender Systems • Content-Based • Try to extract knowledge from source based upon human orientated knowledge • Constraint-Based • Complex set of constraints defining product wanted including ‘soft’ constraints • Collaborative Based • Try to analogise from the experience of others

17. Virtual Markets • Virtual Marketplace • Agents created by different users will try to buy and sell products • Follow predefined strategy to maximise value for user • Virtual Auctions • Very interesting and challenging area • Especially useful for second-hand goods • Note: A lot of ‘new’ products sold on ebay

18. Agent Negotiation • Protocols • Rules of Virtual Marketplace • E.g. Dutch Auction • Apply to all agents • Strategies • rational strategy to maximise utility function • relevant to individual agents

19. Agent Negotiation II • Economics Research • Research equilibrium of market based negotiation • Nature of protocols affects equilibrium • Game Theory • Emphasis on protocols and self-interested strategies • Self-interested strategies can have weird effects in Agent “mob psychology”

20. Agent Negotiation III • Distributive Negotiation • Single sized pie distributed among people • E.g. Kasbah • Integrative Negotiation • Try to increase size of pie through negotiation