Knowledge & Networks

John GoubeauxAriane GravelDarren Hardy

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(Fleming, 1996)

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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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

KMIKSL

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Information retrieval

P

R

(Frakes & Baeza-Yates, 1992)

•Precision

•Recall

P NrelevantNretrieved

R Nrelevant _ retrivedNrelevant _ corpus

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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

BT (Broader Topic)NT (Narrower Topic)

RT (Related Topic)SA (See Also)UF (Used for)RF (Refer from)

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

Psychology, Pathological -- Substance abuse -- Alcoholism

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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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