_______________________________________
From: Resource Description and Access / Resource Description and Access
[RDA-L@LISTSERV.LAC-BAC.GC.CA] On Behalf Of J. McRee Elrod [m...@slc.bc.ca]
Sent: March-16-11 11:51 AM
To: RDA-L@LISTSERV.LAC-BAC.GC.CA
Subject: Re: [RDA-L] RDA "draft"
>>If there is a mnemonic feature to RDA numbering, I've not figured it
>out.
There is a mnemonic structure to RDA, as well as repeating patterns that are
very useful to grasp. The logic flows from an entity-relationship analysis
which should make cataloging data more intelligible to database builders. We
look at each "thing" -- each entity -- and then we look at how they connect
together.
The overall structure for all the sections in RDA is:
1) entities, which are divided into groups of elements organized by the primary
user task (identify, select, obtain-- where applicable)
2) relationships between those entities
Each group of entities has a General Guidelines chapter, and there is a
mnemonic structure beginning each section:
x.0 - Scope
x.1 - Terminology
x.2 - Functional Objectives and Principles
x.3 - Core Elements
x.4 - Language and Script
followed by conventions and elements that are common to all the entities in the
particular section
Each entity follows a pattern where groups of elements are organized by user
task:
Manifestation & Item
- elements used to Identify the entity
- elements used to Select the entity
- elements used to Obtain the entity
Work & Expression
- elements used to Identify the entity
- elements used to Select the entity
Person, Family, Corporate Body
- elements used to Identify the entity
Place
- elements used to Identify the entity
For elements used to identify, there are guidelines at the end of each
respective chapter on how to contruct authorized access points to represent
those entities. This is quite a change from AACR2, where the comparable rules
are primarily for constructing "headings". In RDA, the individual elements of
each entity are reviewed first, and only as a secondary step is the
construction of headings ("authorized access points") brought up.
"Authorized access point" is the common name for headings, and main entry
strings for works and expressions, which are treated as special constructions
to represent the entity. "Identifiers" (control numbers, URIs, and so) are the
other method of representing entities.
So for the task of "identifying" there are three very important distinctions
that are used in the organization of the respective chapters:
1) individual elements that help users identify an entity
2) identifiers such as control numbers
3) authorized access points
This is a useful separation to understand, since it reflects the different ways
in which we can represent an entity. It doesn't have to be an authorized access
point (a "heading"). It can be an identifier (which works better for machine
processing). Or it can be a cluster of elements for the Entity grouped together
and displayed on the screen as such.
For relationships between entities, a similar mnemonic structure occurs for the
General Guidelines chapter for each set of relationships:
x.0 - Scope
x.1 - Terminology
x.2 - Functional Objectives and Principles
x.3 - Core Elements
x.4 - Recording Relationships (the conventions used to represent entities in
the relationship elements)
followed by additional conventions and elements that are common to all the
relationships in the particular section, including
x.5 - covers Relationship Designators, which are listed in full in the
Appendices
All relationships follow a basic pattern:
Element for relationship + Convention used to represent Entity + Optional
Relationship Designator
Example for relationship between Work and Person entities:
Element -- creator
Value -- Hemingway, Ernest, 1899-1961 [convention used is "authorized access
point"]
Designator -- author
Example for relationship between Work and Work entities:
Element -- related work
Value -- Curriculum report (Reston, Va.) [convention used is "authorized access
point"]
Designator -- absorbed
Example for relationship between Person and Corporate Body entities [Corporate
Body is "Miles Davis Quartet"]:
Element -- related person
Value -- Davis, Miles [convention used is "authorized access point"]
Designator -- founder
All RDA relationships follow this basic pattern. These relationships are mapped
into MARC fields in numerous ways, because MARC uses a large variety of
conventions to record relationships. RDA, by comparison, and once the pattern
is understood, uses a very straightforward, predictable, and often mnemonic
structure.
Thomas Brenndorfer
Guelph Public Library
