Proposal No. 2002-13

DATE: May 8, 2002
REVISED:

NAME: Changes for Faceted Application of Subject Terminology (FAST) Subject Headings

SOURCE: OCLC, Library of Congress (LC)

SUMMARY: This paper presents the changes that are needed to accommodate the scheme for FAST subject headings as conceptualized by OCLC in the MARC 21 format.

KEYWORDS: FAST; ; Record status (AD); Field 7XX (AD); Linking Entry fields (AD); Field X48 (AD); Chronological heading (AD)

RELATED: 2002-DP03 (Jan. 2002)

STATUS/COMMENTS:

05/08/02 - Made available to the MARC community for discussion.

06/17/02 - Results of the MARC Advisory Committee discussion - Approved as amended. Participants agreed that code o (Obsolete) should be defined in Leader/05 for obsolete FAST headings that remain in authority files. The definitions of codes d (Deleted), s (Deleted: heading split into two or more headings) and x (Deleted; heading replaced by another heading) should be revised to emphasize that they are used for headings that have been removed from authority files. There was consensus that NLC and LC will agree on which tags to use for chronological headings as a result of NLC's comment that X48 fields are associated with titles.

07/11/02 - Results of LC/NLC review - Agreed with the MARBI decisions.

12/19/02 - Subsequent discussion at LC, in consultation with NLC, resulted in retaining the X48 tags. Likewise, it was later decided not to change the definitions of Leader/05 values s (Deleted: heading split into two or more headings) and x (Deleted; heading replaced by another heading) since their current definitions sufficiently emphasized that headings have been removed from authority files.

Proposal No. 2002-13: Changes for FAST subject headings

1. INTRODUCTION

OCLC is developing a subject vocabulary, Faceted Application of Subject Terminology (FAST), for application to web resources that is based on LCSH but is intended to be easier to apply. The plan is that the FAST vocabulary could be applied to resources by non-catalogers and that resource discovery would then be possible through a controlled vocabulary, FAST. FAST's relationship with LCSH would facilitate cross file retrieval of resources to which LCSH has been applied.

The FAST thesaurus contains records derived from subject heading fields from bibliographic records in WorldCat that are faceted into pieces, and then validated against the LCSH or LC Name Authority File and/or against subject heading application rules. OCLC has worked with its FAST advisory group and the Network Development and MARC Standards Office to work within the MARC 21 format and minimize the format changes that would be needed to accommodate the FAST system as currently conceived.

Discussion Paper No. 2002-DP03 discussed changes needed for FAST headings at the ALA Midwinter 2002 MARBI meeting. Participants requested that the use of FAST headings in bibliographic records be considered in a follow-up proposal. There was some concern that a record status of delete is being used, since most library systems cannot load deleted records. Since this code is only used internally within the FAST file, this should not be a problem.

2. FAST relationship to LCSH

2.1 Characteristics of the FAST system

FAST is built on LCSH and OCLC intends to keep the systems in synch.

The relationship of the new vocabulary to LCSH is the following:

• LCSH strings are broken into separate headings by type of component: topical, geographic, chronological, form.



• Topical components that are precoordinated in a single subfield would be left precoordinated (e.g. Rain and rainfall, Diplomatic and consular service, American). Eventually some topicals, such as events, may be broken also into components (e.g., Gettysburg, Battle of, Gettysburg, Pa., 1863 would become topical Gettysburg, Battle of, geographic Pennsylvania - Gettysburg and chronological 1863).



• LCSH topical components that are not precoordinated will be congruent with FAST headings (e.g., Astronauts).



• Geographic components would all be converted to indirect, generally under the smallest level in which they are fully contained that correspond to levels in the GAC list, (e.g., King Ranch (Tex.) would become Texas - King Ranch and Kenwood (Chicago, Ill.) would become Illinois - Chicago - Kenwood). Geographics would be keyed to GACs. Some geographics may not have corresponding authority records if they have not been used in bibliographic records in WorldCat.



• Chronological components would be converted to all numeric (e.g., War of the Mascates, Brazil, 1710-1714 would be three FAST headings, a topic War of the Mascates, a geographic Brazil, and a chronological 1710-1714; 20th century would become 1900-1999).



• Forms would be based on LCSH, including current work to extract forms from topicals.
  
  
• Separate FAST authority records would be made for all topical, geographic and form components, and perhaps a few chronological components that are term based (e.g., Carboniferous).
  
  
• Names and titles would be treated in a later phase (except for geographic names).

Examples:

The initial FAST file will consist of LCSH headings that were used as subjects in WorldCat records. These are faceted and validated against the subject and name authority files as well as other sources. About 45% of the FAST topical headings match headings in the LCSH authority file.

2.2 Links between LCSH and FAST

Linkages will be maintained between FAST headings and the corresponding LCSH heading. Among other uses, these links will enable OCLC to be able to automatically apply updates from LCSH to FAST. All FAST headings that correspond to an established LCSH heading will be linked through the 7XX fields. OCLC feels the 7XX are adequate for this purpose with the second indicator value of '0' to identify the source thesaurus as LCSH.

2.3 Links between Obsolete FAST headings and their replacements

For the initial version of FAST, faceting will be done only at the subdivision level. The LCSH heading Gettysburg, Battle of, Gettysburg, Pa., 1863 will initially be established in FAST as a single topical heading. However, in later phases, it is anticipated that headings such as this will be further faceted. When this heading is further faceted, OCLC will make the original FAST heading obsolete and create, as needed, new headings to replace the now obsolete heading. The obsolete records will be coded as Delete records in the FAST file but they will be retained in the file as a guide for replacing the obsolete heading.

The further faceting of the example would result in three headings:

Topical: Gettysburg, Battle of

Geographic: Pennsylvania - Gettysburg

Chronological: 1863

In the FAST Delete record, OCLC needs to carry these authorized FAST replacement headings.

To allow for algorithmic updating, OCLC prefers to have them in separate fields rather than in a formatted note such as field 682 (Deleted Heading Information) that is currently used for the information. These headings could be recorded in the 7XX fields with $2fast indicating they are the corresponding valid FAST headings.

These links could be used to automatically update the heading or guide an assigner related FAST record and from there determine appropriate replacement headings.

The FAST headings in the 7XX field in the Delete record may in some cases be one-for-one replacements or a one-to-many as in the case of the above example. In some cases, the obsolete FAST heading can always be replaced by a set of one or more headings.

In other cases, they may represent a split of a string that disallows automatic replacement. The obsolete heading Nurses and nursing is an example of this type of split.

FAST will retain some old heading forms like Nurses and nursing in the authority file as obsolete headings to provide the links to the replacement headings.OCLC needs to be able to reflect that change in FAST and to distinguish it (via the $w byte) from the other changes made in FAST.

Indicating replacements versus splits is like the current Leader/05 (Record Status) where a delete is marked to indicate whether automatic replacement is possible or not. For the FAST implementation, OCLC has proposed that this information be carried at the field rather than the record level (as now) since only one part of the string may need to be marked to disallow automatic replacement. At the record level the simple value d (Deleted) would probably be used. The following new character position is needed in subfield $w:

For subsequent changes to FAST headings, another Delete record might also be kept and the replacement heading(s) recorded in the 7XX fields.

The earlier discussion of Discussion Paper No. 2002-DP03 indicated a concern that a record status of deleted is being used, since most library systems cannot load deleted records. Since this code is only used internally within the FAST file for assistance in assigning headings and these records will not be distributed, this should not be a problem.

OCLC wants to use field 688 (Application History Note) to record the dates that a heading changed in FAST.

Some minor changes will need to be made to the description of the values in Leader/05.

3. Field for Chronological Headings

FAST needs separate fields for each of the facets it uses. Most are already established: topical (150), geographic (151), and form (155), but a new field will be needed for the chronological facet. Tag X48 is proposed for both the bibliographic and authority formats as follows:

4. Kind of Record

Consideration was also given to changing the 008/09 (Kind of Record) from a (Established heading) to c (Traced reference) when the Record Status (Leader/05) was changed to Delete, but that would appear to serve no purpose. The fact that the record is a Delete record says the 1XX, which was formerly valid, is now invalid or obsolete. The c (Traced reference) value is intended to enable one to indicate in a valid record that the heading is invalid and was probably never valid. Changing the value to c would indicate that the heading was never valid. The value in the Leader/05 overrides the 008/09 as it currently does with Delete records. The 008/09 value would stay the same as it was when the record was valid in order to preserve the information that the heading was formerly valid.

5. Use in bibliographic records

It is anticipated that non-catalogers would be the primary users of FAST, however, any authorized user could add FAST headings to bibliographic records. Regardless of the presence or absence of any LCSH headings in the record, the FAST heading(s) would be retained as part of the master bibliographic record in appropriate 6XX fields, and indicated as $2 fast.
See section 7 for examples of bibliographic usage.

6. Proposed Changes

In summary, the following major change is needed:

In the MARC 21 Authority Format:

In the MARC 21 Bibliographic Format: define the following field for chronological headings:

7. Examples

Example 1

FAST record:

FAST records after it has been decomposed (no authority record is required for the chronological heading):

Example 2

Obsolete FAST record

FAST records:

Example 3

Bibliographic record

100 1 Foster, Dianne.
245 10 Charlevoix, Michigan / $c photography by Ken Scott ; text by Dianne Foster.
260 Charlevoix, Mich. : $b Petunia Press, $c c1998.
300 160 p. : $b ill. ; $c 26 cm.
651 0 Charlevoix (Mich.) $v Pictorial works.
650 0 Summer resorts $z Michigan $z Charlevoix.
651 7 Michigan $z Charlevoix. $2 fast
650 7 Summer resorts. $2 fast
655 7 Pictorial works. $2 fast

Associated Authority Records

040 $f fast
150 Summer resorts
550 Resorts
550 Seaside resorts
750 0 Summer resorts $0 (DLC) sh 85130430 $wna

040 $f fast

151 Michigan $z Charlevoix
751 Charlevoix (Mich.) $0 (DLC) n 82062705 $wnb

040 $f fast
155 Pictorial works

Example 4

FAST record for obsolete LCSH heading (This will only appear in the FAST thesaurus.)

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