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ICT619 Intelligent Systems Topic 8: Intelligent Agents.

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Presentation on theme: "ICT619 Intelligent Systems Topic 8: Intelligent Agents."— Presentation transcript:

1 ICT619 Intelligent Systems Topic 8: Intelligent Agents

2 ICT619 S2-052 Intelligent Agents  What is an intelligent agent?  Why intelligent agents?  What intelligent agents can do for us  Characteristics of a good agent  Types of agents  Building intelligent agents  Intelligent agents in E-Commerce  Intelligent agent design - state-of-the-art and future

3 ICT619 S2-053 What is an intelligent agent? Underlying concept -  An autonomous computational entity designed to perform a specific task, without direct initiation and continuous monitoring on part of the user  Evolved in the last decade or so  Distinct from conventional programs Additional properties:  Some level of intelligence, from fixed rules to learning engines enabling adaptation to changes in the environment  Acts reactively, but also proactively  Social ability - communicates with user, system, other agents as required  Cooperates with other agents to carry out more complex tasks  Agents may move from one system to another to access remote resources or to meet other agents

4 ICT619 S2-054 What is an intelligent agent? (cont’d)  “Agents” or “software agents” do not necessarily possess all features of intelligent agents  Wide range of variation in capabilities, eg,  Some perform tasks individually while others are cooperative  Some are mobile- able to move across a network, others are not  Some communicate via messages, some don't communicate at all  Not all agents learn and adapt themselves  Robots are physical agents

5 ICT619 S2-055 Why intelligent agents?  More and more everyday tasks becoming computer-based  An increasing number of untrained users using computers  Current human-computer interfaces require users to initiate all tasks and monitor them  Intelligent agents engage in a cooperative process with the user to increase the effectiveness and efficiency of human- computer interaction – the interface agent  Phenomenal growth in information availability  Intelligent agents can be a tool for relieving the user of this information overload  Intelligent agents can act as personal assistants to the user to manage information

6 ICT619 S2-056 What intelligent agents can do for us  Carry out tasks on the user’s behalf  Train or teach the user  Help different users collaborate  Monitor events and procedures  Specifically, intelligent agents can help us with  Information retrieval  Information filtering  Mail management  Recreational activities – selection of books, music, holidays

7 ICT619 S2-057 What intelligent agents can do for us (cont’d) Information filtering agent  One type is the selection of articles from a continuous stream to suit particular user needs  User can create “news agents” and train them by giving positive or negative feedback for articles recommended  The use of key words alone can be restrictive  Underlying semantics must be extracted for more effectiveness

8 ICT619 S2-058 What intelligent agents can do for us (cont’d) Electronic mail agent  Assist users with electronic mail  Learn to prioritize, delete, forward, sort and archive mail messages on behalf of the user  May use intelligent system techniques like case-based reasoning  Can associate a level of confidence with its action or suggestion  Use of “do-it” and “tell-me” thresholds set by user  May involve multi-agent collaboration

9 ICT619 S2-059 What intelligent agents can do for us (cont’d) Selection agents for entertainment  Potential for becoming popular and commercially successful  Use “social filtering” – correlation between different users to make recommendations on books, CDs, films etc.  E.g., if user A liked items X and Y, and user B liked item X and Z, then item Z may be recommended for user A

10 ICT619 S2-0510 What intelligent agents can do for us (cont’d) Some other current and emerging applications of intelligent agents:  air traffic control  air craft mission analysis  control of telecommunications and network systems  provision and monitoring of medical care  monitoring and control of industrial processes  on-line fault diagnosis and malfunction handling  supervision and control of manufacturing environments  transactions management in banks and insurance companies  E-commerce, tourism

11 ICT619 S2-0511 Characteristics of a good agent Communication  Must communicate well with the user  Should understand user’s goals, preferences and constraints  Useful communication requires shared knowledge on  language of communication  problem domain Web search engines  accept key words and phrases (some knowledge of the language) but  understand nothing about the documents they retrieve (no domain knowledge)  Solution: provision of machine readable ontology - a definition of a body of knowledge including its components and their relationships

12 ICT619 S2-0512 Characteristics of a good agent (cont.) Action  Agent must be able to take some action and not just provide advice  Present state of web technology limits capability of Internet agents - no standard interface for agents  As the Internet becomes more agent-friendly, more capable agents will emerge Autonomy  An agent can be much more useful if it can act autonomously  The right level of autonomy for a task must be found

13 ICT619 S2-0513 Characteristics of a good agent (cont.) Adaptation  Can gain user confidence by learning user preferences  An agent unable to adapt to changing environment, is of limited utility.  Adapting to user needs and preferences can be achieved by using data mining techniques such as clustering  Agent forms clusters of users with similar features  User's expectations can then be anticipated by placing the user in one of these clusters and analysing the cluster

14 ICT619 S2-0514 Types of agents  Based on operational characteristics and functional objectives:  Collaborative agents  Collaborate to - integrate information and - negotiate with other agents to resolve conflict - Provide solutions to inherently distributed problems, e.g., air traffic control  Reactive agents  Act by stimulus-response to the current state of the environment  Each reactive agent is simple and interacts with others in a basic way  Complex patterns of behaviour emerge from collective interaction.

15 ICT619 S2-0515 Types of agents (cont’d) Interface agents  Provide user support and assistance  Cooperate with user in accomplishing some task in an application.  Interface agents learn:  by observing and imitating the user  through receiving feedback from the user  by receiving explicit instructions  by asking other agents for advice (from peers)  Examples:  Personal assistants performing information filtering, mail management.

16 ICT619 S2-0516 Types of agents (cont.) Mobile agents  Programs that migrate from one machine to another.  Execute in a platform-independent execution environment  Example, Java applets running on a Java virtual machine.  Practical but non-functional advantages:  Reduced communication cost  Asynchronous computing (when you are not connected)

17 ICT619 S2-0517 Types of agents (cont.) Two types of mobile agents:  One-hop mobile agents (migrates to one other place)  Multi-hop mobile agents (roam the network from place to place) Example applications:  Distributed information retrieval  Telecommunication network routing

18 ICT619 S2-0518 Types of agents (cont.) Information agents  Manage information  Manipulate or collate information from many distributed sources.  Can be mobile or static.  Examples:  BargainFinder compares prices among Internet stores for CDs  Jasper works on behalf of a user or community of users and stores, retrieves and informs other agents of useful information on the WWW. Heterogeneous agents  Consist of at least two agents from different agent types  Needs agent common language (ACL) for agents to communicate.

19 ICT619 S2-0519 Building intelligent agents Two main problems to overcome:  Competence  How does agent acquire knowledge needed to decide  when to help the user  what to help the user with, and  how to help the user?  Trust  How to guarantee user comfort in delegating tasks to the agent  Approaches to building agents 1.User-programmed agents 2.Knowledge-based agents 3.Machine-learning approach

20 ICT619 S2-0520 Building intelligent agents (cont’d)  The main problem with user-programmed approach - requires high level of user competency - user must be able to  Recognise opportunity for employing an agent  Take initiative to create an agent  Impart specific knowledge to agent by codifying it in a special language  Maintain agent’s knowledge by updating rule base with time  The issue of trust tied up with users’ trust in their own programming skills.

21 ICT619 S2-0521 Building intelligent agents (cont.) In the knowledge-based approach,  The agent is endowed with knowledge about application and user  At run-time, agent uses the knowledge to recognise user’s plans and find opportunities to contribute to them  Example of knowledge-based agent: the UCEgo designed to help users solve problems in using the UNIX operating system.

22 ICT619 S2-0522 Building intelligent agents (cont.) Problems with knowledge-based approach -  Both competence and trust are issues of concern  The problem of competence relates to the competence of the knowledge engineer  Knowledge-base is fixed and cannot be customised to specific user needs  User’s trust is affected as agent is programmed by someone else

23 ICT619 S2-0523 Building agents – the machine learning approach  Metaphor of a personal office assistant  Agents start with minimum knowledge and learn from: 1.Observation and imitation of user 2.User feedback – direct, indirect 3.Training by user 4.Other agents  User can build up model of agent decision making – more trust  Agent capable of explanation

24 ICT619 S2-0524 Development of an agent through learning

25 ICT619 S2-0525 Building agents – the machine learning approach Advantages:  Less work from end-user and developer  Agent customises to user/organisation habits/preferences  Helps distribute know-how and competence among different users Some examples:  Agent for e-mail handling  Agent for meeting scheduling  Agent for electronic news filtering  Agent for recommending books, music

26 ICT619 S2-0526 Intelligent agents in E-Commerce  Rapid growth continuing in E-commerce  Information about products and vendors easily accessible  But transactions are still largely unautomated  Six fundamental stages of the buying process:  Need identification  Product brokering  Merchant brokering  Negotiation  Purchase and delivery  Product service and evaluation

27 ICT619 S2-0527 Intelligent agents in E-Commerce (cont’d)  In the need-identification stage, agents can help in purchases that are repetitive or predictable  Continuously running agents can monitor a set of sensors or data streams and take actions when certain pre-specified conditions apply  Many agents use rule-based or data mining techniques to discover patterns in customer behaviour to help customers find products

28 ICT619 S2-0528 Intelligent agents in E-Commerce (cont.)  In the merchant brokering stage, on-line shopping agents can look up prices for a chosen product for a number of merchants  Many business-to-business transactions are negotiated  In web auction, customers are required to manage their own negotiation strategies  Intelligent agents can help with this

29 ICT619 S2-0529 Examples of on-line shopping framework with agent mediation PERSONA Logic Firefly Bargain Finder AuctionBotJango Auction Bot T@T Need identification Product brokering *** Merchant brokering *** Negotiation*** Payment & delivery Service & Evaluation

30 ICT619 S2-0530 Examples of on-line shopping framework with agent mediation (cont’d)  Software agents are helping buyers and sellers cope with information overload and expedite the online buying process  Agents are creating new markets (eg, low-cost consumer goods) and reducing transaction costs  Use of agents in e-commerce still at an early stage  Visit http://agents.umbc.edu/Applications_and_Software/Ap plications/Electronic_Commerce/index.shtml http://agents.umbc.edu/Applications_and_Software/Ap plications/Electronic_Commerce/index.shtml http://agents.umbc.edu/Applications_and_Software/Ap plications/Electronic_Commerce/index.shtml for more

31 ICT619 S2-0531 Intelligent agent design - state-of- the-art and future  Few agents are available with all the desired characteristics  Agent technology still in experimental stage  Autonomy and mobility already achievable  Example: Java applets which execute independently across networks  But autonomy limited so far in practical use due to the agent-unfriendliness of the current web technology

32 ICT619 S2-0532 Intelligent agent design - state-of- the-art and future (cont’d)  A major limiting factor is lack of ontologies essential for effective communication  Building and maintaining ontologies remains a major challenge  Some of the proposed capabilities to be developed in future intelligent agents include:  Learning as well as reasoning, which are characteristics of machine intelligence  Interacting with the external environment through sensors

33 ICT619 S2-0533 REFERENCES  Chin, D., Intelligent Interfaces as Agents. In Intelligent User Interfaces, J. Sullivan and S. Tyler(eds), ACM Press, New York, 1991.  Hendler, J., Making Sense out of Agents, IEEE Intelligent Systems, March/April 1999, pp.32-37.  Hendler, J., Is There an intelligent Agent in Your Future? http//www.nature.com/nature/webmatters/agents/agents.html  Maes, P., Agents that Reduce Work and Information Overload, Communications of the ACM, Volume 37, Issue 7 (July 1994), pp. 30-40. pp.  Maes, P., Agents that Buy and Sell, Communications of the ACM, Volume 42, Issue 3 (March 1999), pp. 81-91. pp.  Sheth, B. and Maes, P. Evolving Agents for Personalized Information Filtering. In Proceedings of the Ninth Conf. on Artificial Intelligence for Applications. IEEE Computer Society Press, 1993  UMBC Agent News - http://agents.umbc.edu/agentnews/current/ http://agents.umbc.edu/agentnews/current/  http://www.agentland.com/ http://www.agentland.com/


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