Research in Knowledge Representation, Reasoning, and Acting

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Research inKnowledge Representation, Reasoning,
and Acting

• Stuart C. Shapiro
• Professor, CSE
• Director, Center for Cognitive Science
• Director, SNePS Research Group
• Faculty Member, Interdisciplinary MS
• in Computational Linguistics
• Fellow, AAAI

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Long-Term Goal

• Theory and Implementation of
• Natural-Language-Competent
• Computerized Cognitive Agent/Robot
• and Supporting Research in
• Artificial Intelligence
• Cognitive Science
• Computational Linguistics.

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Cassie

• A computational cognitive agent
• Embodied in hardware
• or Software-Simulated
• Based on SNePS and GLAIR.

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Cassieas a Wumpus World Agent

• From Stuart C. Shapiro and Michael Kandefer, A
  SNePS Approach to The Wumpus World Agent or
  Cassie Meets the Wumpus. In Leora Morgenstern and
  Maurice Pagnucco, Eds., IJCAI-05 Workshop on
  Nonmonotonic Reasoning, Action, and Change
  (NRAC'05) Working Notes, IJCAII, Edinburgh,
  2005, 96-103.

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perform get(gold) No breeze here. No stench
here. Exploring the cave... Found a safe room...
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I am in room (1, 0), facing east No breeze
here. No stench here. Exploring the cave... Found
a safe room...
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(No Transcript)
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I am in room (1, 1), facing south I feel a
breeze. No stench here. Exploring the
cave... Found a safe room...
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(No Transcript)
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I am in room (0, 1), facing west No breeze
here. No stench here. Exploring the cave... Found
a safe room...
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(No Transcript)
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I am in room (0, 2), facing south I feel a
breeze. No stench here. Exploring the
cave... Visiting an old room... This is boring.
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(No Transcript)
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Exploring the cave... Visiting an old
room... This is boring.
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Exploring the cave... Visiting an old
room... This is boring.
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(No Transcript)
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Exploring the cave... Found a safe room...
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I am in room (2, 0), facing east I feel a
breeze. No stench here. Exploring the
cave... Visiting an old room... This is boring.
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(No Transcript)
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Exploring the cave... Visiting an old
room... This is boring.
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Exploring the cave... Visiting an old
room... This is boring.
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(No Transcript)
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Exploring the cave... Visiting an old
room... This is boring.
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(No Transcript)
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Exploring the cave... I'll chance a move...
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I am in room (1, 2), facing south No breeze
here. I'm grabbing for the gold. No stench
here. I'm going home!
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(No Transcript)
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(No Transcript)
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(No Transcript)
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(No Transcript)
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Score 966.
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Important SNePS Features 1

• First-person beliefs
• Not third-person truth about agent or world
• Beliefs are current beliefs
• Even if about the past
• On-line acting
• Reified propositions as well as acts
• Neither states nor times are privileged

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Important SNePS Features 2

• SNeRE acts with operational semantics
• External acts
• go(right)
• do(grab)
• senseFor(breeze)
• Control acts
• snsequence(go(right), go(right))
• Mental acts
• believe(p)
• disbelieve(p)

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Important SNePS Features 3

• SNeRE policies integrate reasoning acting
• whendo(See(glitter), do(grab))
• ActPlan(find(home),
• snif(if(In(cell(0,0)),
  do(stop)),
• else()))

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Important SNePS Features 4

• Use of SNePS andor connective
• and belief revision
• for state constraints
• andor(1,1)Facing(north), Facing(south),
• Facing(east), Facing(west)
• Facing(east)
• gt Facing(north), Facing(south), Facing(west)
• believe(Facing(south))
• Facing(south), Facing(north),
• Facing(east), Facing(west)

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Important SNePS Features 5Nondeterministic Choice

• Have(gold)
• gt(all(r1)(In(r1)
• gt ActPlan(explore(cave),
• withsome(?r2, ?d1,
• SafeNewRoom(r1, ?r2, ?d1),
• snsequence3(turn(?d1),
• 
  move(forward),
• 
  believe(Bored(0))),
• ltelse clausegt))))

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Important SNePS Features 6Numerical Quantifier

• wheneverdo(Feel(breeze),
• withsome/3(?r, In(?r),
• believe(nexists(1,4,4)(c)(Adjacent(?r,c)
• 
  Contains(c,pit)))))

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Agents in a Virtual Reality Drama

• Stuart C. Shapiro, Josephine Anstey, David E.
  Pape, Trupti Devdas Nayak, Michael Kandefer,
  Orkan Telhan, The Trial The Trail, Act 3 A
  Virtual Reality Drama Using Intelligent Agents.
  In R. Michael Young John Laird, Eds.,
  Proceedings of the First Annual Artificial
  Intelligence and Interactive Digital
  Entertainment Conference (AIIDE-05), AAAI Press,
  Menlo Park, CA, 2005, 157-158.
• Stuart C. Shapiro, Josephine Anstey, David E.
  Pape, Trupti Devdas Nayak, Michael Kandefer,
  Orkan Telhan, MGLAIR Agents in Virtual and other
  Graphical Environments, Proceedings of the
  Twentieth National Conference on Artificial
  Intelligence (AAAI-05), AAAI Press, Menlo Park,
  CA, 2005, 1704-1705.

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SNePS Multi-Agents
Bad guy agents hassling a human participant
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Reconsideration

• Frances L Johnson and Stuart C. Shapiro,
  Dependency-Directed Reconsideration Belief Base
  Optimization for Truth Maintenance Systems,
  Proceedings of the Twentieth National Conference
  on Artificial Intelligence (AAAI-05), AAAI Press,
  Menlo Park, CA, 2005, 313-320.

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Reconsideration Example
Credibility order s?d gt ?(s ? d) gt s gt d
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DDR Graph
p?q
p?r
s?t
p
q
r
s
t
q
q
r
r
p,p?q,q
s,s?t,t
p,p?r,r
p,p?q,q
p,p?q,q
p,p?r,r
p,p?r,r
m?r,r,m
p,p?v,v
p,p
p,p
p,p
p,p?v,v
p,p?v,v
p
m?r
v
m
v
v
w?v,w,v
p?v
w?v
w
n
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For More Information

• Shapiro http//www.cse.buffalo.edu/shapiro/
• SNePS Research Group http//www.cse.buffalo.edu/s
  neps/
• Meets Tuesdays 9-11, 45 Baldy Hall
• Join us!