Introduction | Limitations and caveats | |
Basic approach and principles | Verifying LCSH | |
Forms and construction |
This
general introduction to Library of Congress Subject Headings (LCSH) is based on
a trainer’s notes used in introducing
copy cataloguers to the basics of LCSH.
These notes cover general principles of LCSH and general points on the
valid construction of LCSH. The process
of subject analysis – figuring out the topic, topics, or genre of a work – is
not covered here. The focus is primarily
on the cataloguing of non-literary works.
These introductory notes have been designed to be used in conjunction with the reading of sections of Subject Cataloging Manual: Subject Headings -- especially:
Additional local documents about subject headings are available through our local documentation list under “Subject headings.”
Provision of subject access | Number of subject headings | |
Subject cataloguing vs indexing | Order of subject headings | |
Principle of specificity |
A. Provision of subject access. Subject headings are access points with
standardised forms of terms, names, and uniform titles that reflect the topic
or genre of a work -- what a work is about or the form or type of the work. People with interest in a particular topic, not with a specific
title or author in mind, should be able to use to find records for relevant
works. Personal, corporate, and geographic
name headings, as well as uniform title headings, may be used as subject
headings, when a work is about the person, body, place, or other work.
B. Subject cataloguing vs.
indexing: LC’s subject heading system is intended to
reflect major subjects -- generally those covered in 20% of the text
or more (i.e., about 1/5 of the text – you don't need to count pages
specifically, but you may want to scan contents). There are some exceptions, if a named person or entity is
particularly stressed.
Assigning
subject headings, therefore, is not the same as detailed indexing, which may
cover a topic or name that appears only once, briefly, in a work. A set of subject headings just constitutes
a concise, standardised summary of what a work is about. One common temptation of
cataloguers-in-training is to try to provide subject access that is too
detailed.
C. Principle of specificity: As LC states -- "Assign headings
that are as specific as the topics they cover." In other words, generally don't assign
broad, general headings when dealing with specific aspect of that topic. However, a valid heading that is as specific
as the topic is not always available. Try
to be as specific as you can while still covering the topic.
Groups of subtopics of overarching
general topic:
1. If 3 or fewer subtopics of
general topic are discussed:
a. If the subtopics cumulatively
represent the entire topic (i.e., there are no significant aspects of the
broader topic that are not covered in the work), assign a heading for the broader
topic.
E.g. Book on vertebrate and invertebrate
animals; animals are either vertebrate or invertebrate.
Assign: Animals
not Vertebrates
Invertebrates
b. If the subtopics cumulatively
represent only part of the entire topic (i.e., there are significant
aspects of the broader topic that are not covered in the work), assign a
heading for each of the subtopics.
E.g. Book on mice and rats, both
sub-categories of rodents; there are types of rodents other than mice and rats.
Assign: Mice
Rats
not Rodents
2. If more than 3 subtopics of
general topic are discussed: assign a
heading for the broader topic.
(There are occasional exceptions, if 4 subtopics of a very broad
topic are discussed.)
E.g. Book on mice, elephants, bears, and
deer.
Assign: Mammals
not 4 headings, each representing the
different type of mammal.
D. Number of subject headings: The number of subject headings assigned varies
from work to work. Sometimes one is
adequate; sometimes several are needed.
1. Many works deal with more than
one focussed topic – a group of related topics. Each major topic deserves a subject heading.
2. You often need multiple subject
headings to bring out multiple facets of the same topic. For example, for a work about an economic
problem in a given place: you may end
up with a heading for the type of problem (in that place if the rules allow
geographic subdivision of that topical heading), and a heading for the place,
subdivided by "Economic conditions."
NB: Subject heading strings (see below) are
another way to try to bring out multiple facets or subfacets of a subject.
3. A work may deal with a topic on
more than one level, e.g., a general discussion of a concept, with case
studies that illustrate the concept in a specific context; a study of a social
phenomenon, including a specific examination of the history of that phenomenon
in a particular place. Headings should
reflect different levels if there is at least 20% of the work devoted to each
level.
E.g. In the same record:
Women $z Nicaragua.
Women.
6 subject headings or so are considered
adequate for most books. There should rarely
be more than 10 subject headings (we have made some exceptions, usually
with very specialised materials such as theses and detailed anthropological and
archaeological studies of Latin American Indians).
E. Order of subject headings
: The general principle is to assign
headings in order of the importance of the subject in the work. Thus, the first heading should reflect the
most central topic of the work. The
order is not always straightforward, however, when a cluster of headings is
needed to bring out one topic (cf. I.D.2 above).
Please note that the MARC tag number for
the type of subject heading is not a factor in assigning the order of
headings.
Basic (main) heading | Subdivisions |
In
checking a subject heading, you naturally need to confirm that its meaning is appropriate
for the content of the work. In
addition, if verification of the heading is required, you need to be sure that
it is valid in its construction and application according to LCSH
rules. This section deals with valid
construction.
Topical | Uniform title | |
Name | Geographic |
1. Topical (MARC tag 650): May represent: a concrete
object, animal, etc.; a category of people, animals, or objects; a more
abstract concept, belief, process, or phenomenon; an institution, etc.
A topical heading may be a term consisting
of a single word or a phrase.
a. Single word: probably the most common form.
E.g. Housing
Women
Savannas
b. Phrase: Various methods of constructing a topical
phrase heading include:
1) Direct order
E.g. Housing policy
Foreign exchange administration
2) Inverted order; inverted
headings include a comma. In theory,
the more significant term is given first, then followed by a modifier. An inverted topical heading functions almost
like a hierarchy, although it is not formally structured as such through MARC
coding, since a phrase is used rather than a coded subdivision.
E.g. Authors, Mexican
Farms, Small
3) Term plus qualifying term;
the qualifier is in parentheses and should resolve ambiguities or make the
context of the term clearer.
E.g. Stress (Physiology)
Stress (Psychology
Consumption
(Economics) [i.e., not
tuberculosis, not energy or food consumption ]
4) A topical phrase heading may
include prepositions.
E.g. Violence in motion pictures
Children of alcoholics
5) A topical phrase heading may
include related terms connected with "and."
E.g. Banks and banking
Cities and towns
6) Occasionally, a phrase consists of
list of terms seen as related, with 2 terms plus "etc."
E.g. Comic books, strips, etc.
E.g. Survival after airplane accidents,
shipwrecks, etc.
7) Combination or modification of
above.
E.g. Banks and banking, Central [compound
direct, plus
inverted addition]
Registers of births, etc. (Canon
law) [preposition, one phrase, plus
"etc."; followed by
parenthetical qualifier]
Creative ability in science
2. Name -- personal, corporate,
or conference (MARC tag 600,
610, or 611): The form of a name
heading used as a subject should be the same as that in the name authority file,
so the form of an access point is the same whether its function in the record
is to represent an author, responsible body, or subject. Therefore, the rules for construction are
covered in AACR2 revised (chapters 22 and 24) and the associated LCRI. (This authority work will be covered later.)
3. Uniform title (MARC tag 630): The form of a uniform title heading used as a subject should
be the same as that in the name authority file, so the form of the access
point is the same whether its function in the record is to represent the
uniform title for the content of a work, for the content of part of a work, for
a series, or for the subject (a work discussed in the work in hand). Therefore, the rules for construction are
covered in AACR2 revised (chapter 25) and the associated LCRI. (This authority work will be covered later.)
4. Geographic (MARC tag 651): There are two categories, with various complicating factors:
a. Places that have or had
jurisdictional status on some level:
Such places -- e.g., countries, cities, and provinces -- have governments that
could issue works and thus could function as corporate authors.
E.g. Argentina
Buenos Aires (Argentina)
Louisiana
Jefferson Parish (La.)
North Yorkshire (England)
LC might set up a jurisdiction in its
name authority file or its subject authority file -- depending on the situation
and, historically, who got to it first.
The form of access point should be the same whether its function in the
record is to represent a responsible body or subject. The rules for construction are covered in AACR2 revised (chapter
23) and the associated LCRI. Additional
relevant rules show up in the Subject Cataloging Manual: Subject Headings.
b. Geographic features without
jurisdictional status: Such places --
e.g., individual mountains or mountain ranges, rivers, bays; regions larger
than countries, including continents and groups of countries; regions within
countries that do not correspond to political divisions -- could only relate to
a work as subjects.
E.g. Alps
Olympus, Mount (Greece)
Mississippi River
Europe
West Indies
Atlantic Coast (Nicaragua)
LC sets up subject authority records for
headings for geographic features.
Guidelines are provided in the Subject Cataloging Manual: Subject
Headings.
For additional information about
geographic headings, see “Introduction to Geographic Headings.”
B. Subject heading strings: Subdivisions
If a subject heading consists of a
string, with a heading and one or more subdivisions, and verification is
required, you need to be sure that the string is constructed correctly:
1. Valid
a. Valid to use that subdivision
under that heading or type of heading.
E.g. Farms, Small $z Colombia: You need to verify that the topical heading
"Farms, Small" may be subdivided geographically (with a $z subfield
or pair of $z subfields for the place).
Camus, Albert, $d 1913-1960 $v
Congresses: You need to verify that the
form subdivision "Congresses" may be used under names of persons.
b. Subdivision is in the correct
form.
Please
note: The function and construction of
a subdivision is not the same as that of a subject heading. Therefore, the valid form of a subdivision
will not necessarily be the same as that of a subject heading with a similar
meaning.
E.g. 650
0 Economic history.
651 0 Chile $x Economic
conditions.
Subdivisions
with similar meanings may also be different under different types of headings.
E.g. 650
0 Children $x Religious life. [under classes of persons]
651 0 Ethiopia $x Religious
life and customs. [under
places]
2. In the correct order
when more than one subdivision is present.
E.g. 650 0
Women $z Italy $x Social conditions.
but
650
0 Women $x Employment $z Italy.
(For
more information about subject subdvisions, see "Some Common Library of Congress Subject
Subdivision Patterns and Caveats.")
LCSH: Some limitations and caveats
A. The list of LC subject
headings is not comprehensive:
It is based on "literary warrant" -- i.e., based on headings that
have actually been used to reflect topics in works catalogued at LC or
at libraries where SACO proposals for new subject headings have been submitted,
then accepted at LC. You may
continually run up against the problem of not finding a heading for a major
topic that the work covers. (Our trained original cataloguers sometimes submit SACO proposals for new subjects.)
B. The choice and form of
headings are not necessarily current:
The LCSH terms have evolved over time, but they can never be totally up
to date. Although LC has made
considerable efforts to keep up to date in its subject terminology, you will
still find terms that sound archaic or that diverge from common terms (e.g.,
the subdivision "$x Antiquities").
Currently, weekly lists with updated, new, or deleted terms are issued;
quarterly lists are printed in issues of the LC Cataloging Service Bulletin
(CSBs) with new headings that LC thinks may be particularly timely.
E.g. 650
0 Man
is now obsolete; switched (in Winter
1997) to
Human beings
E.g. recent heading (Fall 2002): 650
0 Marine ecotourism
E.g. recent heading (January 2007): 650
0 Asian American women in motion pictures
C. The meaning and usage of a
term in LCSH may not be what we might expect from its use in regular spoken
English. You sometimes need to
consult scope notes and/or bib records to figure out what the term really means
in LCSH.
E.g. 650
0 Archaeology $z Mexico -- refers to the discipline of archaeology,
Mexican archaeologists,
etc.
651
0 Mexico $x Antiquities --
refers to archaeological sites, artefacts, etc.
D. The form of a subject heading
or subject string is not always easy to predict. Plans are in the process of being
implemented to update and simplify patterns of subject heading
construction. For example, more phrase
headings now appear in direct rather than inverted order.
E.g. Women, Deaf
is now
obsolete; switched to: 650 0
Deaf women
E.g. Societies, Primitive
is now
obsolete; switched to: 650 0
Primitive societies
Different sources have different advantages and limitations when searching topical, genre, and geographic headings. One may be more appropriate than the other, depending on the type of heading or subdivision that needs to be verified.
Online LC/SACO subject authority file: | Printed LC subject authority file | |
in OCLC Connexion | Subject Cataloging Manual: Subject Headings | |
in Voyager |
A. Online LC/SACO Subject Authority
File
a. Advantages:
1) Most current and authoritative.
2) Includes records for freefloating subdivisions.
3) Available on your desktop.
4) Now fairly easy to search.
5) If you do original cataloging
online, the authority files in OCLC are right in the same place.
b. Limitations:
1) You need to learn and remember some
searching quirks:
-- Derived search key:
-- 5,3 for 151 topical headings and 781 geographic subdivisions
E.g. artis,col for Artist colonies
E.g. greec,ath for Athens (Greece) via 781 $z Greece $z Athens
-- Subdivisions can be included
E.g. art,col for Art $x Collectors and collecting
-- “Scan” searches:
-- sca su: -- for 150 topical and 151 geographic headings, 180 topical subdivisions, and 185 form subdivisions
-- sca gg: -- for 151 geographic headings only
-- Browse search based on beginning word or phrase
-- Keyword searches:
-- su: -- for 150 topical and 151 geographic headings, 180 topical subdivisions, and 185 form subdivisions
-- gg: -- for 151 geographic headings and $z geographic subdivisions only
-- Keyword search, with optional truncation, for matching character string anywhere in heading or reference
E.g. gg:wetland? retrieves records including
151 Nakivubo Urban Wetland (Uganda), 151 Ballona Wetlands (Calif.), 451 Sedgemoor (England : Wetlands), etc.
-- Punctuation (parentheses and commas) can be omitted
-- Initial search cannot include
subdivisions; heading strings including subdivisions display in list of hits
-- May result in response: "Too many records found for your search"
2) A subject authority record may have
scope notes and clues to usage, but it may not; the same search does not pull
up bib records that could help clarify the meaning and application of a subject
heading.
2. in Voyager -– through Staff
Subject Headings Search
a. Advantages:
1) Available
on your desktop.
2) Quite easy to search, few quirks to
learn, e.g.:
-- All types of subject headings are grouped together regardless of tag
-- Punctuation can be ignored
-- Subdivisions can be included
3) Using the same search, bib records
are usually also retrieved, which can be compared for examples of the actual
use of the heading.
4) Subject authority records in
Voyager occasionally include local modifications, such as clarifications,
additional cross-references, and so forth.
b. Limitations:
1) Not necessarily current. Most subject authority records were loaded
into our local authority file in January 1991, and many have not been checked
or updated since then.
2) Not as comprehensive as the LC/SACO
Subject Authority File: It only
includes records for headings that we have actually already used in bib records
(with a few exceptions), and there are often no authority records for subject headings first used in our bib records after January 1991.
3) Of limited use for searching
subdivisions – authority records are usually only available in our local file
for non-free-floating subdivisions; information about a free-floating
subdivision may be located within an entry for a comparable heading (which may
not have the same format and thus may need to be searched differently).
4) Keyword searching of authority records is not available in Voyager.
B. Printed LC Subject Authority
File -- "Red books"
1. Advantages:
a. Includes introductory, explanatory
information.
b. Some people find it easier to
read: quicker to scan and easier on the
eyes.
2. Limitations:
a. Out of date almost as soon as it is
printed. (29th ed.: 2006)
b. Not available at your desk.
c. Of limited use for searching
subdivisions -- only non-free-floating ones are included, or information about free-floating subdivisions within
an entry for a comparable heading (which may not have the same format and thus
may need to be searched differently).
C. Subject Cataloging
Manual: Subject Headings (SCM:SH)
Consulting the Subject Cataloging Manual:
Subject Headings – on Cataloger’s Desktop or in print form – is most
appropriate for:
1. General introductory information
about subject headings and their assignment.
2. Free-floating subdivisions: lists, with numerous scope notes.
3. Geographic headings and
subdivisions: information on their
construction.
4. Guidelines on headings and
subdivisions covering particular topics; certain specific headings and
subdivisions. (Not comprehensive)
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