Information Dynamics

1
Information Dynamics Interoperability

• Presented at
• NIT 2001
• Global Digital Library Development in the New
  Millennium
• Beijing, China, May 2001, and
• DELOS Digital Library Brainstorming Meeting
• San Cassiano, Italy, June 2001
• Ronald L. Larsen
• University of Maryland

2
Digital Library

• the collection of services and information
  objects
• that support users in dealing with information
  objects and their organization and presentation,
• available directly or indirectly via electronic
  means.

Barry M. Leiner, The Scope of the Digital
Library, DLib Working Group on Digital Library
Metrics
3
Heterogeneous, Federated Systems

• cooperating systems where individual
  components are designed or operated
  autonomously.
• components evolve independently
• all components call on each other efficiently
  and conveniently.

Andreas Paepcke, et. al., Interoperability for
Digital Libraries Worldwide, CACM 41,4
4
Things we all know

• Processor power
• Disk storage
• The Web
• Digital libraries

5
Processor power once precious, now ubiquitous
http//www.intel.com/intel/museum/25anniv/hof/moor
e.htm
6
Disk storage once costly, now nearly free
http//www.lesk.com/mlesk/diskprice.gif
7
The Web once a novelty, now a necessity

• World Wide Web contains 20 terabytes of
  information in 1 billion documents
• Deep web contains 8,000 terabytes in 550
  billion documents

http//www.completeplanet.com/tutorials/deepweb/su
mmary03.asp http//www.lesk.com/mlesk/ksg97/ksg.ht
ml
8
Digital Libraries once technical, now societal

• Valued as cultural resources
• Focus for large-scale digitization
• Opportunities for museums, libraries,
  professional associations,
• Still largely stand-alone entities
• Need for interoperable services

9
Things were learning

• Interoperability is

Necessary
Hard
Complex
10
Interoperability Digital Library Components
Services

• Definition
• Functional and logical interchangeability
• Well-defined, publicly known interfaces
• Principles
• Common abstractions
• Open interfaces to services
• Extensibility

http//www.dlib.org/dlib/may99/payette/05payette.h
tml
11
Interoperability

• Syntactic (structural relationships within data)
• Communication, transport, storage and
  representation
• Z39.50, ISO-ILL, XML,
• Semantic (interpretation of term usage and
  meaning)
• Different terms to describe similar concepts
• e.g., 'Author', 'Creator', and 'Composer'
• Identical terms to describe different concepts
• term ambiguity

Adapted from http//www.ukoln.ac.uk/interop-focus/
about/
12
Term ambiguity

• not all squids are superconducting quantum
  interference devices.
• - Jim Hendler, DARPA

13
Interoperability

• Syntactic (structural relationships within
  data)
• Communication, transport, storage and
  representation
• Z39.50, ISO-ILL, XML,
• Semantic (interpretation of term usage and
  meaning)
• Different terms to describe similar concepts
• Identical terms to describe different concepts

• Organizational (implications on support
  structures)
• Resource ownership and control
• Staff (changing skill needs and user communities)
  
• Inter-community (supporting new relationships)
• Multi-disciplinary research
• Cross-sector operations (e.g., libraries, museums
  and archives)
• International (bridging diversity)
• Differences in culture, law, and practice
• Differences in language
• Analytic (understanding intent)
• Context task dependencies
• Temporal spatial relationships

Adapted from http//www.ukoln.ac.uk/interop-focus/
about/
14
Process-centric Design

• What are the functions?
• How does the data flow?
• How do processes interact?
• To communicate data
• To synchronize operations
• What resources are required?
• How are resources allocated?

15
Information-centric Design

• What information is required?
• When is it needed?
• Where does it originate?
• Where will it be used?
• How can it get there?
• What happens to it on the way?

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Information vs. Representation
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Information Dynamics

• Information
• Explicit perceived
• Implicit inferred
• Represented encoded
• Dynamics
• Location availability
• Timeliness relevance
• Value confidence
• Objective
• Goal represented in utility function
• Context domain of utility function
• Action maximize utility over domain

What is needed?
Where is it?
Will it help?
18
Controlling Retrieval
Precision Recall curves from the TREC6
Conference
http//trec.nist.gov/
19
Steps toward analytic interoperability

• Instrumented test-beds
• Better metrics
• Interoperable information substrate
• Semantic web
• XML
• RDF
• Ontologies
• Time location-aware agents
• Context-aware clients

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Information Dynamics in Digital Libraries

• Framework for analytic interoperability
• Consider information value in context
• Recognize temporal dependencies
• Adapt user services to user needs

Understand (and exploit) the role time and
location play in the value of information.