LIS 204:
Introduction to
Library and Information Science
Week Nine
Kevin Rioux, PhD
Information Organization
Ways of looking at information organization
– How knowledge is organized by society
– How knowledge is organized in a library or database
In LIS the primary motivation for organizing information ==>
RETRIEVAL (facilitates/improves ACCESS)
– Our professional mandate states that we need to create and
maintain systems to organize material
– Also a stewardship function
• Taking care of materials
• Preservation of materials
Major challenges
• Very quickly, large amounts of materials (aka, “knowledge”,
“information”, “data”) are constantly being added to vast
amounts of extant knowledge.
– How to organize all of this appropriately and in ways that will
benefit the user?
• Not only physical items, but e-materials
– E-materials are subject to deterioration
– E-materials are extremely numerous
– E-materials are often ephemeral
• Organization of representational records
– Cards, OPAC records, etc.
Goal of organization schemes
Reflect (as much as possible) the way people normally seek out
information (none are perfect)
Be easy to implement by staff and users
Be flexible enough to accommodate all extant and new knowledge.
Intuitive categorization schemes
NOT GOOD ENOUGH for accurate
Intellectual tools that aide in organization of materials (often
depend on each other)
Classification systems
Controlled vocabularies, thesauri and subject headings
Library catalog and rules (AACR2)
Indexes, abstracts, and bibliographies
The act of organizing all knowledge into some kind of systematic order.
– allows for description of items as well as suggests relationships
between items
– suggests physical arrangement in a library
– Suggests a “mental” order for users
Based on:
– Subject--what the item is about
– Discipline--a related body of knowledge that defines a particular
approach to looking at phenomena
DCC (Dewey Decimal Classification)
Most common in the U.S. and most widely used in the world
First proposed by Melvil Dewey in 1876
Divides knowledge into 10 major “classes”
Main Dewey Classes
100-- Philosophy, parapsychology,
occultism, psychology
600--Technology and the applied
700--The arts
800--Literature and rhetoric
300--Social Science
900--Geography, history
500--Natural Sciences and
DDC classes, cont’d.
In each class, there are subclasses and sub-subclasses, and sub-subsubclasses that indicate greater specificity.
– The notation digits can get fairly long
– Remember you are working with *decimals*, which indicate a
*fraction*. Thus 795.5 is larger than 795.395, and should be
shelved (and shifted) in its relative location accordingly.
DDC drawbacks
A closed system--range of numbers is limited to 000 to 999.
– As new disciplines emerge, they must be accommodated into the
existing ten classes--problematic for things not imagined in
Dewey’s time
– Biased toward Western cultures--doesn’t easily accommodate nonWestern ideas
LOC (Library of Congress Classification)
An alphanumeric system
– 20 main classes indicated by letters
– Each notation has 1-3 letters, followed by 1-4 integers
– Classes can be expanded by decimals
Developed by the LOC to deal with its very large collection in the early
20th Century
About 75% of academic libraries use LOC
Controlled Vocabulary
A list of preferred descriptive terms, and rules for assigning these
– Provide consistency for descriptions as well as author and title
– Give guidance when items are very close in nature
– Provide a system of relationships between items
– Reduce error and ambiguity
– Suggest broader and narrower terms and give the proper
equivalent term
Works in tandem with controlled vocabulary scheme
– Thesauri are developed in natural language (e.g., in terms that
people are likely to use in everyday speech)
– These thesauri provide links between natural language and
controlled vocabulary
• Allows authors, catalogers, etc., to position their item within controlled
• Allows for researchers to select the “correct” controlled vocabulary term
to retrieve materials
• Helps ensure consistency in the cataloging and retrieval processes
Thesauri terms are often called “descriptors”
Are critical to electronic retrieval systems
LCSH (Library of Congress Subject Headings)
• An accepted authority of subject headings for library catalogs
and indexes.
• Acts as a kind of index to the classification scheme, giving
classification numbers assigned to any given topic.
– E.g. “Germany” is included in many different LOC record
notations. By looking at the LCSH, you can see all the
headings where “Germany” exists, thus aiding retrieval.
• LCSH are used to develop MARC records, which in turn
increase standardization across collections, thus aiding retrieval.
Other subject heading schemes:
Sears List of Subject Headings
– Simpler than LCSH
– Used by smaller libraries
– Extremely specific and somewhat complex
– Created by the National Library of Medicine (NLM
– Used for the Index Medicus
Subject heading issues
Reflect a cultural bias?
May not reflect the way people think about subjects (e.g., overly
academic), thus is a hindrance to retrieval and use
Some subject headings are quickly outdated
Library catalogs
Describe all the holdings of the facility, and facilitate retrieval.
Each item in the collection has a *record*, either a card or an electronic
These records are created using Anglo-American Cataloging Rules,
2nd Edition (AACR2) created in 1974.
Electronic records are most often in MARC format (Machine Readable
Cataloging), which provides fields for specific pieces of data about the