Knowledge & Networks
John Goubeaux
Ariane Gravel
Darren Hardy
What is knowledge?
• Information relates to
description, definition, or
perspective
(what, who, when, where)
• Knowledge comprises
strategy, practice, method, or
approach (how)
• Wisdom embodies principle,
insight, moral, or archetype
(why)
(Bellinger, 2004)
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(Fleming, 1996)
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Epistemic communities
• Produces small-t local truth,
not big-T universal Truth. (Miller & Fox, 2001)
• Epistemology (Oxford)
 The theory of knowledge, esp. with regard to
its methods, validity, and scope.
 The investigation of what distinguishes
justified belief from opinion.
• What do we know? How do we know it?
• Shared concepts, language, symbols
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The Information Age
• Epistemic communities
 What are our social institutions for
knowledge? (e.g., science, libraries)
 How does ICT change them?
• Key questions
 Can networks improve these institutions?
 How do online communities support epistemic
communities?
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Roles
• Information seeker
 Search, Browse
• Information provider
 Authorship, Aggregation
• Knowledge managers
KMI
KSL
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Information retrieval
•Precision
N relevant
P
N retrieved
P
•Recall
N relevant _ retrived
R
N relevant _ corpus
R
(Frakes & Baeza-Yates, 1992)
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Information seeking
• Lancaster (1979)
 Information need -> stated request ->
selection of database -> search strategy ->
search in database -> screening of output
• Pharo & Järvelin (2006)
 “Irrational” searchers vs. IR-Rational researchers
 Disjointed incrementalism
 Searchers learn during a search process
 Searchers have subjective & dynamic information needs over
time
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Knowledge management
• Categorization
 Controlled vocabulary, taxonomy
• Search
 Full text or metadata
• Collaboration
 Flow in social networks
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Categorization
• Library of Congress Subject Headings
 To assign information to a subject
 Get a degree, become a librarian
 To find information on a subject
 Talk to a librarian
 Go to the Card Catalog
 Wander the stacks
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LCSH Example
Psychology, Pathological -- Substance abuse -- Alcoholism
Substance abuse (May Subd Geog)
[HV4997-HV5840 (Social pathology)]
[RC563-RC568 (Psychiatry)]
UF Abuse of substances
Addiction, Substance
Addictive behavior
Chemical dependence
Chemical dependency
Substance addiction
BT Crimes without victims
Psychology, Pathological
SA subdivision Substance use under
classes of persons and ethnic groups
NT Aerosol sniffing
Alcoholism
Betel chewing
Caffeine habit
Church and substance abuse
Drug abuse
Dual diagnosis
Solvent abuse
Tobacco habit
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BT (Broader Topic)
NT (Narrower Topic)
RT (Related Topic)
SA (See Also)
UF (Used for)
RF (Refer from)
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The Semantic Web
(Berners-Lee et al., 2001)
• Today: hypertext links related content
• Tomorrow: links content by meaning
• The hype: “The Semantic Web can assist the
evolution of human knowledge as a whole”
 Structured content (XML)
 Meaning (RDF)
 Ontology (OWL) - automated reasoning
 A graph; nodes = concepts, links = semantics
 Or, a taxonomy plus set of inference rules
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Seriously, onto-whatnow?
• FOAF
• SIOC
(Harth et al., 2004)
• SWOOP
(Hendler et al., 2005)
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Social tagging
• 100% pure simplicity
• Author
 Whatever “tags” she thinks appropriate
 No controlled vocabulary, no suggestions
• Social network dynamics does the rest
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Social tagging examples
• Information seeking
 By popularity (Tag clouds)
 By example (Read an article, see tag)
 By surfing (Edited what’s new page)
• Meets “good enough” standards?
• Application: Social bookmarking
 Technorati
 36.6 million sites, 2.3 billion links
 del.icio.us
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Tag cloud
Adland
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