Knowledge Organization:
Thesauri and Content Standard Principles
Thesauri
1. Introduction to Thesauri:
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Particular genre of controlled vocabularies - specific to info field(?) in this version?
Controlled vocabulary = any kind of designed, finite list of options (e.g. drop down menu
of languages to choose from)
Thesauri Used
- re: information-bearing objects, institutions
- For aboutness (official subject headings)
“Syndetic structure”
Used to name what something is about (classification is where they fit)
Research Papers, for e.g.: Specifically talking about subjects field
- Author keywords are not included
Hierarchical Classification vs. Faceted Classification vs. Thesauri
E.g. “Education”
Hierarchical Classification - e.g. Dewey Decimal System
- Every term / level only has meaning in context of the above terms/levels
Faceted Classification:
E.g. three hierarchical levels: 1). Location then 2). Discipline 3). Level (Primary, Secondary)
- Every item only has one location / place where it lives
Thesaurus Rules / Syndetic Structure:
E.g. ERIC Thesaurus slide put together by Dr. Bullard (rare to see thesaurus visualizations)
Syndetic Structure
- Relationships in subject headings & thesaurus systems
- Thesaurus rules
Three Principles of Organization:
1. Equivalence - which things mean the same thing
2. Hierarchy - which things are more specific variants of another thing - species of a same
thing
3. Other Relationships
a. neither of the above
b. but with intrinsic associations / relationships to another thing
ERIC Thesaurus (Education Resources Information Centre) - has Database
E.g. Physical Education (under / part of ‘Education’)
- Specific kinds of physical education
- Long list of other relationship terms (e.g. athletic coaches)
(increasingly) long list of terms being added for e.g. to one article by a worker at ERIC - can get
messy.
Library Thesauri usually have upper limit (# of allowed terms) per resource.
E.g. with abbreviations:
BT- Broader Term:
- Dance -----> Fine Arts
- Dance has the broader term of Fine Arts
- (unidirectional, solid line / connection)
NT- Narrower Term:
- Dance is a part of Fine Arts
- (solid line / connection, unidirectional - FA ---> D)
- Fine Arts has the narrower term of Dance
RT - Related Term: Dance ←- - - - - > Fine Arts (bidirectional)
Relationships Used in Thesauri:
1. Equivalence
a. “USE” / “Used For”
b. Equivalent Phrases (e.g. air/aeroplanes)
c. Inverted Forms (e.g. bilingual education & education, bilingual) - searches
alphabetized.
d. Acronyms & Abbreviations
e. Antonyms
i.
Uncommonly used
ii.
Searching for “dropouts” ---> should lead to items regarding “Student
retention” (always relevant to first term)
2. Hierarchical
a. Broader term (BT)
b. Narrower term (NT)
3. Associative
a. Related term
Lead-in Terms:
- People using queries / their specific locational spelling etc. to find info
- Goal: direct people to same resource
- E.g. lead-in term of “aeroplanes” -> USE “airplanes”
1. Equivalence Relationship
Upward Posting (query leads to only broader category - e.g. ballet -> dance)
- Often because there aren’t enough resources specific (e.g. to ballet) to justify it having
its own term in a given thesauri context
2. Hierarchical Relationships
Relationship between concept & more specific concept
1. Generic Relationship: link to a more specific type
a. Teachers NT School Teachers
b. Thinking NT Reasoning
2. Instance Relationships: a link to a particular example
a. Seas NT Baltic Sea
b. Wars NT WW2
3. Partitive Relationship: a link to a part
a. Canada NT British Columbia
b. Cars NT Steering Wheel
4. Other Types of Relationships?
a. Children NT Television and Children
Hierarchical Breadth
Hierarchical Depth: all ‘levels’ should be true (e.g. all cats are living things) AKA “transitive”
3. Associated Relationships (related terms)
- Intrinsic relationships - brings together related concepts, but that have another BT/NT
relationship
- Not transitive
- Examples, often:
- Operations & Instruments
- Actions & Products (e.g. Roadmaking RT Roads)
- Causal Relationships (accidents RT injury)
- Field of study & objects studied (e.g. xenobiology RT alien lifeforms)
- When not to use:
- E.g. Insects NT Bees & Flies
- Doesn’t pass tests from previous slide
- Bees & Flies don’t need RT to one another
Thesaurus / Activity: have document speak for itself
(avoid extra / separate text with explanations)
One common way:
- Scope Notes (SN)
- Describes how heading is to be used
- E.g. “Art” here means / encompasses __xyz__, as opposed to more precise
headings such as “Art Products”, “Visual Arts” (basically, go see those if you
need to)
Content Standard Principles
1. Intro
Key Questions:
- Which aspects of a resource to represent?
- What are the constraints placed on those representations?
- Is there a limit on the type of word used, professional knowledge required?
Central Concepts (generally agreed upon as being important to include)
- Title
- Creator (responsible for resource)
- Version (e.g. diff editions, publishing dates)
Other concepts (might want to use / include)
- What it looks like
- Resource type (text, sound recording…)
- Who published it and where
- How to ID resource (ISBN, ISSN, DOI, etc.)
- What resource is about
- Thesaurus terms
- Class number (libraries)
Content Schema vs. Content standards
- Not exactly interchangeable
- Schemas become standards when regulated, managed, shared among institutions
- Schema = ad hoc, personal, idiosyncratic -> standards = professional, controlled, agreed
upon
(Authority) Control:
- Of language & consistency
- Allows for trust in system, results
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Users get used to how system works in one context and can apply it in new one /
institution.
Ability to share / compare results & predict across records, institutions
Structure within record
Bibliographic relationships
- Structure for linking between (related) records in reliable way
Abstraction & Specificity
- How important is it to make similar resources appear the same?
- How important is it to distinguish similar resources from each other?
- What do users need to know / have specified?
Access
- “Access points”
- In a digital environment: what is searchable, filterable?
- What will used need to find, sort, ID & evaluate a record? (e.g. probably don’t need to
know that a give book is 13.27cm wide)
IFLA’s General Principles:
- Everything we’re trying to achieve
- Complex, and principles often in tension with one-another - often trade-offs (e.g.
consistency & standardization vs. convenience of the user - might mean lacking
searchable details they are interested in)
Dublin Core - Example of Content Schema with Minimal Rules
- Even less policed than standard content schema - to be used as (customizable) base for
diff. Orgs, environments
- Sets up common “core” of metadata elements for web-based resource
- Main goal: easier search & retrieval mechanisms
- Across institutions, super broad - e.g. ideally able to search resources by year
across a ton of institutions
- 15 elements
- Dublin Core Qualifiers:
- Able to use more specific version of one of the elements
- E.g. instead of standard ‘date’
- Date digitized / modified / available
Metadata & Cataloguing:
- in practice, each describe different kinds of approaches
- Many parallels between the two
Most Metadata:
- Created specifically to describe digital content
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DC often constantly changes = ‘extent’ of website or page can be difficult to
measure as content evolves & doesn’t have ‘editions’
Harder to control = metadata plays gatekeeping / control role
Choosing / Creating Content Standard:
Consider:
- Balance - Functionality & Simplicity (how to tell the ideal number of elements?)
- Support Human & Machine Use (learn / read etc. differently)
- Support Interoperability
- Metadata from one institution should be readable by another = standardization
- Md from one schema can be readable in another (enabled by translations,
crosswalks)
- Support Extensibility
- Md schema is adaptable for local needs (made specific)
- Extended schema can be simplified for global needs (collapsed using aggregate
tool)
Example: creating a crosswalk between Dublin Core and EAD fields
e.g. “dc.title” maps onto EAD (Header) field “titleproper”
Summary
Each Schema or Standard has:
- Set of values
- Instructions on which elements are necessary
- Instructions on how to modify elements
- Instructions on how to fill out the values
- Possibly a reference to Controlled Vocabs for specific fields / professions
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