Lecture04 2002 09 05 final

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							Lecture 04: Knowledge Representation



                        SIMS 202:
                 Information Organization
                       and Retrieval
             Prof. Ray Larson & Prof. Marc Davis
                      UC Berkeley SIMS
          Tuesday and Thursday 10:30 am - 12:00 am
                          Fall 2002
                     Credits to Warren Sack for some of the slides in this lecture
IS 202 - Fall 2002                                                                   2002.09.05 - SLIDE 1
Today
• Review of Categorization

• From Cognitive Science to AI

• The Vocabulary Problem

• Artificial Intelligence, Knowledge
  Representation,and Commonsense

• Photo Project Assignment 2 Check-In


IS 202 - Fall 2002                     2002.09.05 - SLIDE 2
Categorization
• Processes of categorization are fundamental to
  human cognition
• Categorization is messier than our computer
  systems would like
• Human categorization is characterized by
        – Family resemblances
        – Prototypes
        – Basic-level categories
• Considering how human categorization functions
  is important in the design of information
  organization and retrieval systems

IS 202 - Fall 2002                        2002.09.05 - SLIDE 3
Categorization
• Classical categorization
        – Necessary and sufficient conditions for
          membership
        – Generic-to-specific monohierarchical structure


• Modern categorization
        – Characteristic features (family resemblances)
        – Centrality/typicality (prototypes)
        – Basic-level categories

IS 202 - Fall 2002                               2002.09.05 - SLIDE 4
Properties of Categorization
• Family Resemblance
        – Members of a category may be related to one
          another without all members having any
          property in common


• Prototypes
        – Some members of a category may be “better
          examples” than others, i.e., “prototypical”
          members


IS 202 - Fall 2002                             2002.09.05 - SLIDE 5
Basic-Level Categorization
• Perception
        – Overall perceived shape
        – Single mental image
        – Fast identification

• Function
        – General motor program

• Communication
        – Shortest, most commonly used and contextually neutral words
        – First learned by children

• Knowledge Organization
        – Most attributes of category members stored at this level

IS 202 - Fall 2002                                               2002.09.05 - SLIDE 6
Information Hierarchy



                      Wisdom

                     Knowledge

                     Information

                        Data



IS 202 - Fall 2002                 2002.09.05 - SLIDE 7
Information Hierarchy



                      Wisdom

                     Knowledge

                     Information

                        Data



IS 202 - Fall 2002                 2002.09.05 - SLIDE 8
Today’s Thinkers/Tinkerers
                     George Furnas
                     http://www.si.umich.e
                     du/~furnas/

                     Marvin Minsky
                     http://web.media.mit.
                     edu/~minsky/

                     Doug Lenat
                     http://www.cyc.com/st
                     aff.html

IS 202 - Fall 2002                      2002.09.05 - SLIDE 9
Psychology Methodology




                Theorizing   Experimenting




IS 202 - Fall 2002                           2002.09.05 - SLIDE 10
Computer Science Methodology




                Theorizing




                        System Building


IS 202 - Fall 2002                        2002.09.05 - SLIDE 11
Cognitive Science Methodology




                Theorizing       Experimenting




                        System Building


IS 202 - Fall 2002                               2002.09.05 - SLIDE 12
What is Cognitive Science?
• A definition from Howard Gardner (1986)
  The Mind’s New Science; the five
  symptoms of cognitive science; the first
  two are central, the next three are
  strategic
        – (1) Mental representations
        – (2) Computers
        – (3) Emphasis
        – (4) Epistemology
        – (5) Interdisciplinarity

IS 202 - Fall 2002                     2002.09.05 - SLIDE 13
Symptom 1 of Cognitive Science: Mental
Representations
• To study human cognition it is necessary
  to posit mental representations and
  examine those representations separately
  from the “low level” biological or
  neurological, on one hand, and also
  separately from the “high level” social or
  cultural, on the other hand.
  (adapted from Gardner, 1986)


IS 202 - Fall 2002                    2002.09.05 - SLIDE 14
Symptom 2 of Cognitive Science:
Computers
• Computers are central to any
  understanding of the human mind. They
  are essential both as tools, but also as
  models of how the mind works.
  (adapted from Gardner, 1986)




IS 202 - Fall 2002                   2002.09.05 - SLIDE 15
Symptom 3 of Cognitive Science:
Emphasis
• Cognitive scientists deliberately de-
  emphasize certain factors which may be
  important for cognitive functioning but
  whose inclusion would unnecessarily
  complicate the cognitive-scientific
  enterprise. These de-emphasized factors
  include emotional affect, historical,
  cultural, and other types of context (e.g.,
  issues of embodiment and the senses).
  (adapted from Gardner, 1986)

IS 202 - Fall 2002                     2002.09.05 - SLIDE 16
Symptom 4 of Cognitive Science:
Epistemology
• Cognitive science is concerned with an
  area that has historically been a part of
  philosophy, namely the domain of
  epistemology.
  (adapted from Gardner, 1986)




IS 202 - Fall 2002                      2002.09.05 - SLIDE 17
Symptom 5 of Cognitive Science:
Interdisciplinarity
• Cognitive science is an interdisciplinary
  enterprise.
  (adapted from Gardner, 1986)




IS 202 - Fall 2002                     2002.09.05 - SLIDE 18
Disciplines of Cognitive Science

•     Philosophy
•     Psychology
•     Artificial Intelligence
•     Linguistics
•     Anthropology
•     Neuroscience




IS 202 - Fall 2002                 2002.09.05 - SLIDE 19
The Birth of Cognitive Science

• Symposium on Information Theory, MIT,
  10-12 September 1956
        – Allen Newell & Herbert Simon, “Logic Theory
          Machine”
        – Noam Chomsky, “Three Models of Language”
        – George Miller, “The Magical Number Seven”




IS 202 - Fall 2002                            2002.09.05 - SLIDE 20
The Birth of AI
• Rockefeller-sponsored Institute at
  Dartmouth College, Summer 1956
        – John McCarthy, Dartmouth (->MIT->Stanford)
        – Marvin Minsky, MIT (geometry)
        – Herbert Simon, CMU (logic)
        – Allen Newell, CMU (logic)
        – Arthur Samuel, IBM (checkers)
        – Alex Bernstein, IBM (chess)
        – Nathan Rochester, IBM (neural networks)
        – Etc.

IS 202 - Fall 2002                           2002.09.05 - SLIDE 21
Definition of AI
“... artificial intelligence [AI] is the science of
   making machines do things that would
   require intelligence if done by [humans]”
   (Minsky, 1963)




IS 202 - Fall 2002                          2002.09.05 - SLIDE 22
The Goals of AI Are Not New
• Ancient Greece
        – Daedalus’ automata
• Judaism’s myth of the Golem
• 18th century automata
        – Singing, dancing, playing chess?


• Mechanical metaphors for mind
        – Clock
        – Telegraph/telephone network
        – Computer

IS 202 - Fall 2002                           2002.09.05 - SLIDE 23
Some Areas of AI
•     Knowledge Representation
•     Programming Languages
•     Natural Language Understanding
•     Speech Understanding
•     Vision
•     Robotics
•     Planning
•     Machine Learning
•     Expert Systems
•     Qualitative Simulation

IS 202 - Fall 2002                     2002.09.05 - SLIDE 24
Furnas: The Vocabulary Problem

• People use different words to describe the
  same things
        – “If one person assigns the name of an item,
          other untutored people will fail to access it on
          80 to 90 percent of their attempts.”
        – “Simply stated, the data tell us there is no one
          good access term for most objects.”




IS 202 - Fall 2002                                2002.09.05 - SLIDE 25
The Vocabulary Problem
• How is it that we come to understand each
  other?
        – Shared context
        – Dialogue


• How can machines come to understand
  what we say?
        – Shared context?
        – Dialogue?

IS 202 - Fall 2002                  2002.09.05 - SLIDE 26
Vocabulary Problem Solutions?

• Furnas et al.
        – Make the user memorize precise system
          meanings
        – Have the user and system interact to identify
          the precise referent


• Minsky and Lenat
        – Give the system “commonsense” so it can
          understand what the user’s words can mean


IS 202 - Fall 2002                               2002.09.05 - SLIDE 27
Lenat on the Vocabulary Problem

• “The important point is that users will be
  able to find information without having to
  be familiar with the precise way the
  information is stored, either through field
  names or by knowing which databases
  exist, and can be tapped.”




IS 202 - Fall 2002                      2002.09.05 - SLIDE 28
Minsky on the Vocabulary Problem

• “To make our computers easier to use, we
  must make them more sensitive to our
  needs. That is, make them understand
  what we mean when we try to tell them
  what we want. […] If we want our
  computers to understand us, we’ll need to
  equip them with adequate knowledge.”




IS 202 - Fall 2002                   2002.09.05 - SLIDE 29
Commonsense

• Commonsense is background knowledge
  that enables us to understand, act, and
  communicate
• Things that most children know

• Minsky on commonsense:
        – “Much of our commonsense knowledge
          information has never been recorded at all
          because it has always seemed so obvious we
          never thought of describing it.”

IS 202 - Fall 2002                           2002.09.05 - SLIDE 30
Commonsense Example
• “I want to get inexpensive dog food.”

• The food is not made out of dogs.
• The food is not for me to eat.
• Dogs cannot buy their own food.
• I am not asking to be given dog food.
• I am not saying that I want to understand
  why some dog food is inexpensive.
• The dog food is not more than $5 per can.

IS 202 - Fall 2002                    2002.09.05 - SLIDE 31
Engineering Commonsense
• Use multiple ways to represent knowledge

• Acquire huge amounts of that knowledge

• Find commonsense ways to reason with it
  (“knowledge about how to think”)




IS 202 - Fall 2002                  2002.09.05 - SLIDE 32
CYC
• Decades long effort to build commonsense
  knowledge-base
• Storied past
• 100,000 basic concepts
• 1,000,000 assertions about the world
• The validity of Cyc’s assertions are
  context-dependent (default reasoning)



IS 202 - Fall 2002                 2002.09.05 - SLIDE 33
Cyc’s Top-Level Ontology
  •     Fundamentals          •   Professions      •   Materials
  •     Top Level             •   Composition of   •   Waves
  •     Time and Dates            Substances
                                                   •   Devices
  •     Types of Predicates   •   Agents
                                                   •   Construction
  •     Spatial Relations     •   Organizations
                                                   •   Financial
  •     Quantities            •   Actors
                                                   •   Food
  •     Mathematics           •   Roles
                                                   •   Clothing
  •     Contexts              •   Emotion
                                                   •   Weather
  •     Groups                •   Propositional
                                  Attitudes        •   Geography
  •     "Doing"                                    •   Transportation
  •     Transformations       •   Social
                              •   Biology          •   Information
  •     Changes Of State                           •   Perception
  •     Transfer Of           •   Chemistry
                              •   Physiology       •   Agreements
        Possession
                              •   General          •   Linguistic Terms
  •     Movement
  •     Parts of Objects          Medicine         •   Documentation



                     http://www.cyc.com/cyc-2-1/toc.html
IS 202 - Fall 2002                                               2002.09.05 - SLIDE 34
OpenCYC
• Cyc’s knowledge-base is now coming
  online
        – http://www.opencyc.org/


• How could Cyc’s knowledge-base affect
  the design of information organization and
  retrieval systems?



IS 202 - Fall 2002                    2002.09.05 - SLIDE 35
Multiple Representations
• Minksy
        – “I think this is what brains do instead: Find several
          ways to represent each problem and to represent the
          required knowledge. Then when one method fails to
          solve a problem, you can quickly switch to another
          description.”


• Furnas
        – “But regardless of the number of commands or
          objects in a system and whatever the choice of their
          ‘official’ names, the designer must make many, many
          alternative verbal access routes to each.”

IS 202 - Fall 2002                                     2002.09.05 - SLIDE 36
AI or IA?
• Artificial Intelligence (AI)
        – Make machines as smart as (or smarter than)
          people


• Intelligence Amplification (IA)
        – Use machines to make people smarter




IS 202 - Fall 2002                              2002.09.05 - SLIDE 37
Assignment 0 Check-In
• Deliverables
        – Personal web page
        – Assignments page
        – Email address
        – Focus statement
        – Online Questionnaire

• Feedback
        – Spell-check and grammar-check
        – Simple vs. skeletal

IS 202 - Fall 2002                        2002.09.05 - SLIDE 38
Assignment 2 Check-In
• Deliverables
        – Persona description (brief)
        – Scenario description (brief)
        – Annotated user experience storyboard
        – Group web site
        – Work distribution table on your group web site
        – Photos for your application idea

• Feedback
        – Questions, comments, problems?

IS 202 - Fall 2002                              2002.09.05 - SLIDE 39
Homework (!)
• Read
        – Chapters 3 and 5 in The Organization of
          Information (OI)


• Assignment 2: Photo Use Scenario
        – Due by Thursday, September 12




IS 202 - Fall 2002                             2002.09.05 - SLIDE 40
Next Time
• Metadata Introduction (RRL)




IS 202 - Fall 2002              2002.09.05 - SLIDE 41