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How does OCLC control headings in WorldCat?

Overview

In addition to cataloger-initiated controlling, OCLC uses stand-alone controlling software to evaluate bibliographic records in WorldCat and control headings.

In the research that led to the publication of Online Catalogs: What End Users and Librarians Want, library staff who use WorldCat ranked the need for increased accuracy in name and subject headings as a highly desired improvement. The report on WorldCat quality issued in September 2011 identified a project to control more headings in WorldCat as a priority during OCLC’s fiscal year 2012. The following describes this controlling effort which provides benefits to all users of WorldCat, regardless of which interface they use.

Current controlling functionality in Connexion

The controlling functionality currently available in the Connexion applications enables users to link authority records to headings in master WorldCat bibliographic records. Cataloger-initiated controlling functions facilitate automatic updating of headings in bibliographic records.

  • Connexion users initiate matching headings in bibliographic records to established authority records.
  • The system normalizes the headings in bibliographic records, matches them with authority records, and inserts the linked heading in the bibliographic record.

Current controlling functionality in Connexion and Record Manager

The controlling functionality currently available in the Connexion and Record Manager applications enables users to link authority records to headings in master WorldCat bibliographic records. Cataloger-initiated controlling functions facilitate automatic updating of headings in bibliographic records. Connexion allows controlling to the LC NAF, to LCSH, and to LCGFT. Record Manager allows controlling to those files and others.

  • Connexion users initiate matching headings in bibliographic records to established authority records by using “Control Headings” commands from the Edit drop down menu in the Connexion Client, or by right-clicking with cursor position on a heading and using the “Control Single Heading” command. In Record Manager, users initiate these actions by using “Control All Headings” from the Record dropdown menu, or by right-clicking on a heading and using the "Controlled Heading” command.
  • The system normalizes the headings in bibliographic records, matches them with authority records, and inserts the linked heading in the bibliographic record.
  • In addition to the process described above for controlling single headings, Record Manager users may also select "Copy Authority Data" while viewing an authority record, then select "Apply Authority Data" while their cursor is in a bibliographic field, and a controlled heading will be inserted into the bibliographic record.

Stand-alone controlling software

In 2012, OCLC developed a stand-alone batch controlling service that runs independently. The software evaluates all bibliographic records in WorldCat and controls headings as detailed below.

The software evaluates the following bibliographic records in WorldCat for processing according to different time schedules:

  • Master bibliographic records newly added to WorldCat contributed either through online applications or through batch processes are evaluated daily.
  • Master bibliographic records changed and replaced in WorldCat are evaluated on a pre-determined schedule.
  • Existing master bibliographic records in WorldCat are evaluated as capacity allows.

Currently, OCLC processes around 360,000 bibliographic records daily; these are selected from newly added master records to WorldCat, or bibliographic records that have been changed and replaced in WorldCat.

Criteria for record selection

The software will select candidate bibliographic records for processing that contain the following:

For controlling to the LC-NACO Name Authority file and to LCSH:

  • An 040 field with $b present containing the value eng and at least one of the following controllable fields: 
    • 100, 110, 111, 130
    • 600, 610, 611, 630, 650, 651, second indicator 0
    • 655, second indicator 7, $2 lcgft
    • 700, 710, 711, 730
    • 800, 810, 811, 830
  • An 040 field with $b present but containing a value not equal to eng and at least one of the following controllable fields: 
    • 600, 610, 611, 630, 650, 651, second indicator 0
    • 655, second indicator 7, $2 lcgft
  • A partially or fully controlled heading.

For controlling to the Medical Subject Headings (MeSH):

  • A 65x field with second indicator 2
  • At least one of the following controllable fields:
    • 650, 651, 655

For controlling to the Art & Architecture Thesaurus (AAT):

  • A 650 field with second indicator 7, with $2 aat OR a 655 field with second indicator 7, with $2 aat
  • At least one of the following controllable fields:
    • 650, 655

For controlling to the Māori subjects:

  • 650 with second indicator 7, with $2 reo
  • At least one of the following controllable field:
    • 650

For controlling to the RVM:

  • A 6xx field with second indicator 6 OR a 655 field with second indicator 7 with $2 rvmgf
  • At least one of the following controllable fields:
    • 600, 610, 611, 630, 650, 651, or 655

For controlling to the Canadian Subject Headings:

  • A 650 field with second indicator 5 OR a 651 field with second indicator 5
  • At least one of the following controllable fields:
    • 650 or 651

For controlling to the Canadiana Names:

  • An 040 field with $b containing the value fre AND/OR a 600, 610, 611, 630, or 651 field with second indicator = 6
  • At least one of the following controllable fields:
    • 100, 110, 111, 130, 600, 610, 611, 630, 651, 700, 710, 711, 730, 800, 810, 811, 830

For controlling to the Dutch names (planned for the future):

  • An 040 field with $b containing the value dut
  • At least one of the following controllable fields:
    • 100 or 700

For controlling to the German names and subjects: 

  • 040 $b = ger AND/OR  6xx, second indicator = 7, with $2 gnd
  • At least one of the following controllable fields:
    • 100, 110, 111, 130, 600, 610, 611, 630, 651, 700, 710, 711, 730
       

How the software works

The software does not:

  • Attempt to control unqualified personal names (personal name only that does not include $b, $c, $d, and/or $q).
  • Control a heading to an undifferentiated authority record.
  • Cause automated tag flips of any type.
  • Control a heading to a record containing a 667 "Record generated for validation purposes."
  • Control a heading containing brackets.
  • Control subjects to authority records coded as not valid for subject use.
  • Control names to authority records coded as not valid for name use.

The software will:

  • Automatically expand dates for candidate personal name headings.
  • Partially control series fields and automatically append $v.
  • Maintain the links between non-Latin script headings and their Latin-script equivalents.

The software also makes the following adjustments as needed:

  • Apply any appropriate punctuation changes.
  • Attempt to control partially controlled headings.
  • Uncontrol descriptive heading fields (1XX, 7XX and 8XX) if the value in field 040 in the bibliographic record is other than eng unless those descriptive headings fields are controlled to a thesaurus appropriate to the language given in the subfield b of field 040.
  • Delete a geographic subdivision from a subject heading if the heading can be completely controlled and no element of the heading can be subdivided geographically.

The symbol “OCLCO” is appended in $d of the 040 field in bibliographic records that are modified by the software.

If a bibliographic record is locked, the software skips it and reevaluates it when the lock has been removed.

The new software supplements individual cataloging activity

As with the “Control All” headings function in Connexion and Record Manager, some circumstances prevent the software from controlling all headings in WorldCat records. The software cannot do the manual “Single Control” headings functions that catalogers can do in Connexion and Record Manager. The software cannot control non-qualified personal names, headings that have no exact match or that match only partially, headings that are mis-tagged, headings that contain typographical errors, or other errors that require correction.

OCLC encourages catalogers working in WorldCat to continue using the control headings functions in Connexion and Record Manager when adding or upgrading records as you continue to share your cataloging expertise with the cooperative.