Metadata for the Web Issues and Simple Answers

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Metadata for the WebIssues and Simple Answers

• CS 502 20030219
• Carl Lagoze Cornell University

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Metadata is data about data
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Metadata is semi-structured data conforming to
commonlyagreed upon models, providing
operational interoperabilityin a heterogeneous
environment
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Some untested hypotheses

• Metadata is useful for
• People
• Machines
• More metadata is better
• (semi) automated digital libraries and simple
  metadata

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Some known facts

• Number and variety of metadata vocabularies will
  continue to increase
• The Tower of Babel is a franchise
• There is not one common view of reality
• The one thing I know about metadata is that it
  is expensive (Bill Arms)
• I hate metadata projects because they make every
  other digital library project more expensive
  (Michael Lesk)

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Are metadata and data distinguishable?

• Objectivity?
• Intellectual property?
• Structure?
• Aboutness?

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The fiction of classification
there is no classification of the universe that
is not fictional and conjectural. Jorge Luis
Borges
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Lenses and Views

• All classification does and should provide a
  biased lens or view of reality
• Each view emphasizes certain characteristics and
  hides others

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Reality is Complex
Relationship?
Created byGeorge Castaldo Created on1994
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Objects are Related

• IFLA Entity Model

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Entities, Events, and Agents
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Havent we done metadata already?
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Whats wrong with this model?

• Expensive
• Complex (even for its original goal?)
• Professional intervention (assumes single
  community of expertise)
• Monolithic
• One size fits all approach
• Reflects its centralized system origins
• Bias towards physical artifacts
• Fixed resources
• Incomplete handling of resource evolution and
  other resource relationships
• Anglo-centric

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Web Challenge to Traditional Cataloging

• Scale
• Permanence
• Authenticity
• Organizational Context
• Custodial Control
• Variety

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Internet Commons includes Multiple Communities
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Metadata Takes Many Forms
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Metadata Challenges

• Accommodate multiple varieties of metadata
• community-specific functionality, creation,
  administration, access
• Tensions
• functionality and simplicity
• extensibility and interoperability
• human and machine creation and use

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Interoperability has many facets

• Semantics
• Meaning/classification/ontology
• Models/Structure
• Entities and relationships
• Syntax
• grammars to convey semantics and structure

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Warwick Framework Containing Chaos

• Conceptual Architecture for metadata from the
  Warwick Metadata Workshop (DC-2)
• Conceptual architecture to support the
  specification, collection, encoding, and exchange
  of modular metadata
• Provide context for metadata efforts (including
  Dublin Core)
• avoids the black-hole of comprehensive element
  sets
• focuses interoperability issues at package level

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Metadata Container
Container

Package Dublin Core
Package MARC record
Package Indirect Reference
Package Terms and Conditions
URI
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Modularization Allows Distributed Management

• Communities of expertise (not software vendors)
  are responsible for
• Semantics
• Registration
• Administration
• Access management
• Authority of data
• Sharing and Distribution

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Realities of Web search and discovery

• Search systems are motivated by advertising
• Index coverage is unpredictable and limited
• Too much recall, too little precision
• Index spam abounds
• Resources (and their names) are volatile

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Metadata Part of a Solution

• Structured data about data
• helps to impose order on chaos
• enables automated discovery/manipulation
• Variety across various dimensions
• specialization
• decentralization
• democratization

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Web Metadata ModelsDrill-Down Searching Paradigm

• Moving along a specificity spectrum
• Inter-domain vs. intra-domain terms, models,
  query mechanisms
• One size doesn't fit all
• Cognitive models of searching and browsing

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Drill-down search paradigm
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MetadataPart of the problem
AACR2/MARC
cost
Dublin Core
google
functionality
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Why hasnt metadata worked on the Web?

• Its all about trust
• People are lazy
• Metadata is hard
• No perceived benefit
• Reverse tragedy of the commons
• No agreement on one way to describe things
• Metacrap - http//www.well.com/doctorow/metacra
  p.htm