Introduction to Intelligent Software Agents

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Introduction to Intelligent Software Agents

• Martin Beer,
• School of Computing Management Sciences,
• Sheffield Hallam University, Sheffield,
• United Kingdom
• m.beer_at_shu.ac.uk

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Contents

• Agents as Tools of the Information Society
• Information Society
• Intelligent Software Agent as a tool of
  Information Society
• Benefits from Intelligent Agent
• Fundamental Concepts of Intelligent Software
  Agents
• What is an Agent?
• Definition of Intelligent Software Agents
• Characteristics of Intelligent Software Agents
• Classification

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The Information Society

• On the Way to the Information Society
• Digitization
• Networking
• Internet
• Tools of the Information Society
• Browsers
• Search Engines

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Intelligent Software Agents

• Intelligent Agents are
• a new category of information society tools
• software programs that independently perform
  tasks on behalf of a user in a network
  environment
• Intelligent Agents in the Business Area
• Intelligent Agents in the Private Area

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Economic Potential(1/2)

• Potential Benefit from the Users Viewpoint
• Improvement of efficiency in working with
  internet
• Time-saving
• Increase in speed of arriving at solutions in
  internet
• Improvement of effectiveness in working with
  internet
• Overcome the characteristics of human problem
  solving
• Increase in the transparency and optimizations
• Comparing information from various sources
• User can select the most favorable
• Intelligent agents have made Adam Smiths
  Invisible hand visible in the electronic
  business world

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Economic Potential(2/2)

• Potential Benefit from the Viewpoint of the
  Information and Communications Industry
• Sales for intelligent agent (OVUMs expectation)
• 19 million dollars in 1996
• 357 million dollars in 1998
• 4.6 billion dollars in 2006
• OVUM expects that the agents for private
  household will become the primary innovation
  factor and from the start of the next millennium
  the sales with private households will exceed
  those of business and government

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What is an Agent?

• Agents are autonomous
• Capable of acting independently
• Over their own internal state

System
Output
Input
Environment
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What makes Agents Interesting?

• Trivial (ie non-interesting) agents
• Thermostat
• Unix daemon (biff, ftpd etc)
• An intelligent Agent is a computer system capable
  of flexible autonomous action in some environment
  
• (Mike Wooldridge)
• By flexible we mean
• Reactive
• Pro-active
• social

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Reactivity

• If a programs environment is guaranteed to be
  fixed, the program need never worry about its own
  success or failure
• Example of a fixed environment a compiler
• The real world is not like that
• Things change
• Information is incomplete
• Many (most?) environments are dynamic

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Reactivity

• Software is hard to build for dynamic
  environments
• Program must take into account the possibility of
  failure
• Ask itself whether it is worth executing!
• A reactive system is one that maintains an
  ongoing interaction with its environment and
  responds to changes that occur in it
• (in time for the response to be useful)

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Proactiveness

• Reacting to the environment is easy
• (eg stimulus -gt response rules)
• But we generally want agents to do things for us
• Hence goal directed behaviour
• Proactiveness generating and attempting to
  achieve goals
• Not driven solely by events
• Taking the initiative
• Recognising opportunities

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Social Ability

• The real world is a multi-agent environment
• We cannot go around attempting to achieve goals
  without taking others into account
• Some goals can only be achieved with the
  cooperation of others
• Similarly for many computer environments
  witness the Internet
• Social ability in agents is the ability to
  interact with other agents (and possibly humans)
  via some kind of agent communication language and
  perhaps cooperate with others

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Other Properties

• Mobility
• The ability of an agent to move around an
  electronic network
• Veracity
• An agent will not knowingly communicate false
  information
• Benevolence
• Agents do not have conflicting goals, and that
  every agent will therefore always try to do what
  it is asked of it
• Rationality
• Agent will act to achieve its goals, and will not
  act in such a way as to prevent its goals from
  being achieved at least insofar as its beliefs
  permit
• Learning/adaption
• Agents improve their performance over time

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Definition of Intelligent Software Agents(1/2)

• Three Major Categories of Agents
• Human Agent / Hardware Agent / Software Agent

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Definition of Intelligent Software Agents(2/2)

• Two Major Requirement for Intelligent Agent
• Autonomous Processing
• Communication / Cooperation with other objects
• A Definition of Intelligent Software Agent is
• a software program that can perform specific
  tasks for a user and possesses a degree of
  intelligence that permits it to perform parts of
  its tasks autonomously and to interact with its
  environment in a useful manner
• Information / Cooperation / Transaction Agent

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Information Agent

• Task
• search for information in distributed systems or
  networks
• locate information sources
• extract information from the sources
• filter the information of relevance for the user
  from the total quantity of found information
  using the users interest profile
• prepare and present the results in an appropriate
  form

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Cooperative Agents

• Task
• solve complex problems by using communication and
  cooperation mechanisms with other objects, such
  as agents, humans or external resources
• used when a problem exceeds the capabilities of
  an individual agent or agents already exist that
  already have a solution and whose knowledge can
  be used by other agents
• The demands on intelligence are higher than that
  of pure information agent

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Transaction Agent

• Task
• processing and monitoring of transaction in
  classical database environments and in the areas
  of network management and electronic commerce
• Such agents normally operate in very sensitive
  areas and represent their users for tasks that
  demand a high degree of responsibility, for
  example in the purchase of products using a
  users credit card

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Characteristics of Intelligent Software
Agents(1/2)

• The characteristics can be grouped into two large
  categories internal and external
• Internal properties
• determine the actions within the agent
• Ex the ability to learn, reactivity, autonomy,
  goal-oriented
• External properties
• affect the interaction of several agents or
  human-agent communication
• Ex communication, cooperation

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Characteristics of Intelligent Software
Agents(2/2)
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Internal Properties(1/4)

• Reactivity
• Capability of reacting appropriately to
  influences or information from its environment
• Agent must have suitable sensors or possess its
  own internal model of its environment
• Proactivity / goal-orientation
• Capability for an agent itself to take the
  initiative under specific circumstances
• Require that the agent has well-defined goals or
  even a complex goal system

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Internal Properties(2/4)

• Reasoning / learning
• The intelligence of an agent is formed from three
  main components
• its internal knowledge base,
• the reasoning capabilities based on the contents
  of the knowledge base,
• and the ability to learn or to adapt to changes
  to the environment.
• Reasoning power requires rationality
• Rational processing requires the existence of a
  goal system
• Ability to learn from previous experiences and to
  successively adapts its behavior to the
  environment is as important for the intelligent
  behavior of an agent

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Internal Properties(3/4)

• Autonomy
• Capability to follow its goals autonomously, that
  is, without interactions or commands form the
  environment
• To permit autonomous behavior, agent must be
  provided with those resources and capabilities,
  e.g.
• availability of an electronic network,
• capability to navigate through the
  network(mobility),
• capability to make contact with other
  agents(communication).
• Goal-orientation and ability to learn.

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Internal Properties(4/4)

• Mobility
• Ability to navigate within electronic
  communications networks
• Demands on network environment and raise
  questions regarding security, data privacy, and
  management
• Reduces the network loading. It can go to the
  computer or agents with the required information,
  not sending a series of messages over network.
  Then perform all tasks locally on the target
  computer
• Agency Meeting points, serves as marketplace or
  discussion and communication forum

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External Properties(1/2)

• Communication / Cooperation
• Interaction with its environment(human users,
  other agents, arbitrary information sources)
• Communication require standardized protocol for
  exchange of information
• Cooperation must augment the communications
  capability

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External Properties(2/2)

• Character
• Its desirable for agent to demonstrate human
  traits
• An agents most important characteristics are
  honesty, trustworthiness, and reliability
• It is important that agents with a high degree of
  interaction with people exhibit emotional states,
  such as joy, sadness, frustrations.

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Classification

• Three Criteria
• Intelligence, Mobility, Number of Agents

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Information Agents
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Cooperation Agents
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Transaction Agents
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Agents and Objects

• Are agents just objects by another name?
• Object
• Encapsulates some state
• Communicates by message passing
• Has methods, corresponding to operations that may
  be performed on this state

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Main Differences

• Agents are autonomous
• Agents embody a stronger notion of autonomy than
  objects, and in particular, they decide for
  themselves whether or not to perform an action on
  request from another agent
• Agents are smart
• Capable of flexible (reactive, pro-active,
  social) behaviour, and the standard object model
  has nothing to say about such types of behaviour
• Agents are active
• A multi-agent system is inherently
  multi-threaded, in that each agent is assumed to
  have at least one thread of active control

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Summary

• An agent is a computer system that is capable of
  independent action on behalf of its user or owner
• A multi-agent system is one that consists of a
  number of agents which interact with one another
• In order to interact successfully, agents need
  the ability to cooperate, coordinate and negotiate

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Two key problems

• How do we build agents that are capable of
  independent, autonomous action in order to
  successfully carry out tasks that we delegate to
  them?
• How do we build agents that are capable of
  interacting (cooperating, coordinating,
  negotiating) with other agents in order to
  successfully carry out the tasks that we delegate
  to them, particularly when other agents can not
  be assumed to share the same interests/goals?