CMSC 477/677 Agent Architectures and Multi-Agent Systems

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CMSC 477/677Agent Architectures andMulti-Agent
Systems

• UMBCProf. Marie desJardins
• Spring 2007

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Course information

• Prof desJardins
• ITE 337, x53967, mariedj_at_cs.umbc.edu
• Class mailing list
• agents-class_at_listproc.umbc.edu
• To subscribe, send email to listproc_at_listproc.umbc
  .edu with the line
• subscribe agents-class Your Name

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Todays overview

• Class structure and policies
• Whats an agent?
• Agent exercise
• Next class

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Class structure Syllabus

• Course page http//www.cs.umbc.edu/courses/gradu
  ate/677/spring07/http//www.cs.umbc.edu/courses/u
  ndergraduate/477/spring07/

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Class structure 477 vs. 677

• Slightly different weights for assignments
• Two problem sets for graduate students
• Agent architectures project Graduate students
  must do a more in-depth analysis, relating their
  findings to the research literature
• MAS project Graduate students must include an
  experimental research component, and submit a
  research design
• In general, graduate students are expected to
  show greater depth in their analysis and
  synthesis of ideas

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Class structure Prerequisite

• CMSC 471 or 671 is a prerequisite for the class
• I am flexible about this prerequisite, but if you
  have not had 471/671, and you wish to take the
  class, you must
• Attend an AI review session this Friday (Feb. 2,
  10-12 in ITE 346)
• Be prepared to do additional background reading

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Class structure Participation

• This is a discussion class
• Reading must be done in advance
• Participation countsa lot
• 40/35 of grade is related to class participation
• Class discussion (30/25)
• Do you attend class?
• Are you prepared? Have you done the reading?
  Have you thought about the discussion questions?
• Do you contribute to the discussion with
  insightful questions and comments?
• Paper summaries (5)
• Discussion leaders (5)

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Class structure Agent architecture project

• Agent architecture project 20/15 of grade
• Download one of the architectures we learn about
• Apply the architecture to a domain of your choice
• Deadlines
• Proposal due Feb. 20 (5 of project grade)
• Draft report due Mar. 15 (5 of project grade)
• Demonstration week of Mar. 27 (25 of grade)
• Report due Apr. 3 (65 of grade)

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Class structure MAS paper/presentation

• MAS paper 25 of grade
• Students will select a topic to study in greater
  depth, write a paper, and give a presentation on
  that topic.
• Proposal and bibliography due Apr. 5 (10 of
  project grade)
• Draft report due Apr. 26 (10)
• Final report due May 17 (80)
• MAS presentation 5 of grade
• Presentation on May 1, 3, 10, 15, or 17 final
  exam slot (20)
• Paper review (of another students paper, due May
  3) 5 of grade

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MAS competition

• Multi-agent tournament 10 of grade
• In-class competition
• April 26 (Round One does your agent do
  anything?)
• May 8 (Round Two does your agent do it well?)
• Short report describing design and performance of
  agent (due May 15)

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Policies

• Grading and academic honesty
• Plagiarism, citations

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Plagiarism exercise

• Original passage
• I pledge allegiance to the flag of the United
  States of America, and to the republic for which
  it stands, one nation, indivisible, with liberty
  and justice for all.
• Unacceptable summary
• I promise loyalty to the United States flag, and
  to the country for which it stands, one nation,
  with freedom and fairness for all.

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Plagiarism exercise II

• Original passage
• I pledge allegiance to the flag of the United
  States of America, and to the republic for which
  it stands, one nation, indivisible, with liberty
  and justice for all.
• Acceptable summary
• I promise to be loyal to the United States flag
  and to the USA itself One united country that
  provides basic rights such as liberty and justice
  to all citizens.

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Whats an agent?

• Weiss, p. 29 after Wooldridge and Jennings
• An agent is a computer system that is situated
  in some environment, and that is capable of
  autonomous action in this environment in order to
  meet its design objectives.
• Russell and Norvig, p. 7
• An agent is just something that perceives and
  acts.
• Rosenschein and Zlotkin, p. 4
• The more complex the considerations that a
  machine takes into account, the more justified we
  are in considering our computer an agent, who
  acts as our surrogate in an automated encounter.

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Whats an agent? II

• Ferber, p. 9
• An agent is a physical or virtual entity
• Which is capable of acting in an environment,
• Which can communicate directly with other agents,
• Which is driven by a set of tendencies,
• Which possesses resources of its own,
• Which is capable of perceiving its environment,
• Which has only a partial representation of this
  environment,
• Which possesses skills and can offer services,
• Which may be able to reproduce itself,
• Whose behavior tends towards satisfying its
  objectives, taking account of the resources and
  skills available to it and depending on its
  perception, its representations and the
  communications it receives.

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OK, so whats an environment?

• Isnt any system that has inputs and outputs
  situated in an environment of sorts?

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Whats autonomy, anyway?

• Jennings and Wooldridge, p. 4
• In contrast with objects, we think of agents
  as encapsulating behavior, in addition to state.
  An object does not encapsulate behavior it has
  no control over the execution of methods if an
  object x invokes a method m on an object y, then
  y has no control over whether m is executed or
  not it just is. In this sense, object y is not
  autonomous, as it has no control over its own
  actions. Because of this distinction, we do not
  think of agents as invoking methods (actions) on
  agents rather, we tend to think of them
  requesting actions to be performed. The decision
  about whether to act upon the request lies with
  the recipient.
• Is an if-then-else statement sufficient to create
  autonomy?

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So now what?

• If those definitions arent useful, is there a
  useful definition? Should we bother trying to
  create agents at all?

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Next class

• Reading Wooldridge Chapter 1 and 2 Wooldridge
  Jennings 1995
• Overview by Dr. dJ
• Tuesday reading Wooldridge Chapter 4 Bratman et
  al. 1998
• Discussion leaders!

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Multi-agent exercise

• Getting to know you... getting to know all about
  you... (or at least your label / color...)

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Rules

• Write your name on your card
• You can only talk to one other agent at a time
• The only information you can exchange is your
  agent ID, your (real) name, and your current
  value
• At the end of class, turn in your card with
• the names of your agent neighbors
• your agent value
• one observation about what was hard (or easy)
  about each game

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Game 1 (lined side of card)

• Your agent ID is the circled number
• Each agent must choose a value from A to F
• Your value must be after the values of your
  predecessors, and before the values of your
  successors, as indicated by the arrows on your
  card
• e.g., A ? B and C ? E

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Does global knowledge help?
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Game 2 (unlined side of card)

• Your agent ID is the circled number
• The agent values are B(lue), R(ed), G(reen),
  and Y(ellow)
• You must choose a value that is different from
  the values of your neighbors

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Global knowledge...
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After-action reviewor post-mortem, as the case
may be

• ...