Difference between revisions of "Step 3.0"

Revision as of 10:08, 18 November 2016

Authority Cleanup Overview

The first phase of MARS 2.0 Authority Control comprises a battery of routines that update and correct individual subfields and contiguous pairs of subfields, the purpose of which is to increase the likelihood of finding the appropriate authority match.

These corrections are based on a number of subfield update tables, maintained by MARS 2.0 authorities librarians.

MARS 2.0 subfield correction routines include:

• Updating obsolete forms of subdivisions to the current form
• Correcting common typographical errors
• Expanding abbreviations in subject subfields to their fuller form
• Converting common direct geographic subdivisions to their indirect form
• Deleting subject subdivisions which have been canceled or discontinued
• Correcting spacing, capitalization, and punctuation

Update obsolete subdivisions

MARS 2.0 uses a number of subfield correction tables to correct common errors in LC subfields

 
 — Relations (General) with the United States
 
   changes to:
 — Relations — United States

Correct typographical errors

MARS 2.0 also uses the subfield correction tables to correct common spelling errors in LC subdivisions:

Expand abbreviations

The subfield correction tables also support the expansion of outdated or invalid abbreviations in LC headings to the full form. Changes are made only when the outdated or invalid form is the entire text of the subfield:

Direct-to-indirect geographic conversion

MARS 2.0 uses a table to convert direct geographic subdivisions to the indirect form. Changes are made by the direct-to-indirect subfield conversion program only when the invalid form is the entire text of the $z and there is only one $z in the heading:

Chronological conversion

MARS 2.0 uses a table to convert chronological headings $y to their correct form. Corrections are made to spelling and punctuation as well as to format:

Delete obsolete subdivisions

MARS 2.0 uses a subfield deletion table to eliminate canceled subfields from LC bibliographic headings, deleting subfields only when the invalid form is the entire text of the subfield:

The subfield deletion table also includes common misspellings and typographical errors:

Retain selected subdivisions

The subfield deletion table includes a section that prevents subfield conversions and deletions in headings meeting specific criteria.

 
 — Yearbooks
 
    changes to:
 — Periodicals
    except when  — Yearbooks is part of the subfield pair:
    — Students — Yearbooks

Correct spacing, capitalization, and punctuation

Most errors in spacing, capitalization and punctuation are corrected as an integral part of the authority cleanup and authority matching processes. Routines are also run to correct spacing and punctuation on the following fields:

 
 1XX, 240, 243, 245, 260, 4XX, 6XX, 7XX, 8XX

These processes eliminate any excess spaces in each field, makes sure each field has the correct punctuation within and between each subfield, and makes sure each field has ending punctuation.

 
 original headings:
 100  10 $a Black, Adam, $d 1974-   .$t Crested geckos
 111  20 $a IEEE 1394 (FireWire) Workshop $d (2001, $c Berlin, Germany)
   
 updated headings:
 100  10 $a Black, Adam, $d 1974- $t Crested geckos
 111  20 $a IEEE 1394 (FireWire) Workshop $d (2001 :$c Berlin, Germany)

Authority Matching Overview

While Authority Cleanup improves authority controlled headings using proprietary MARS 2.0 correcton tables, authority matching compares each authority controlled heading in your bibliographic records against authority record headings from any of a number of national and other authority files.

National authority files

Goals of authority matching

Authority matching uses the headings in authority records to update or correct the bibliographic headings so they conform to current standards.

Authority matching is also the basis for providing full authority records for your local system. The goals of authority matching are to:

• Update invalid headings to valid forms based on cross-references found in authority records (convert to the established form of heading)
• Modify headings that have incorrect spacing, punctuation, indicators, or subfield codes to the correct form based on matches found
• Update invalid higher levels of a heading to their valid forms, based on cross-references found in authority records
• Distribute matched authority records to your institution
• Identify headings requiring more attention by your staff, through the use of MARS 2.0 reports

Fields under authority control

MARS 2.0 corrects and updates the full range of authority controlled headings. The following bibliographic headings / fields are included in MARS 2.0 authority control processing:

Subfields disregarded

A number of MARC subfields are disregarded during MARS 2.0 authority matching. In the following headings, the volume designations in fields 810 and 440 $v, the heading linkage information in field 130 $6, and the ISSN in field 440 $x, are all examples of subfield information which is not under authority control:

 
 810   2 $a John Bartholomew and Son. $t Bartholomew world travel series ;$v 10.
 130   0 $6 880-01 $a ”Hsuuan lai his kan” his lieh.
 440   4 $a Romanica Gothoburgensia ;$v 12, 16 $x 0080-3863

Subfields matched or ignored

The table below shows the subfields that are included in the MARS 2.0 authority matching process:

Normalization

Headings from both your bibliographic records and the MARS 2.0 national authority files are normalized before they are compared for matching. MARS 2.0 uses the NACO normalization standard. During normalization:

• Alphabetic characters are converted to uppercase
• The first comma will be retained in $a for personal name headings
• All other punctuation is removed
• Certain diacritics and hyphens are left in for JACKPHY normalization
• All other diacritics are removed
• Special characters are replaced by an alphabetic equivalent
• Subfield codes are removed
• Subfield delimiters for all but first subfield will be left in

 bib record heading:
 $a Architecture $z Brazil $x S'ao Paulo (State)
 
 normalized heading:
 ARCHITECTURE $ BRAZIL $ SAO PAULO STATE

Notice the subfield codes and the diacritic in S'ao Paulo have been discarded when constructing the normalized form of the heading.

Because subfield codes are ignored during the authority matching process, invalid subfield codes do not affect the matching and may be corrected during the process.

For this example, the normalized form of the established heading 1XX in the authority record is:

 authority heading:
 $a Architecture $z Brazil $z S~ao Paulo (State)
 
 normalized heading:
 ARCHITECTURE $ BRAZIL $ SAO PAULO STATE

Since the normalized forms of the bibliographic and authority headings are the same, the established form in the authority record replaces the form in the bibliographic record.

The bibliographic heading then contains the correct diacritic ~ instead of ' and the subfield code for S'ao Paulo has been corrected to $z.

Topics

• Step 3.1 - Generic Name Headings
• Step 3.2 - Tag Flipping
• Step 3.3 - Partial Matches
• Step 3.4 - Split Headings
• Step 3.5 - Series Processing
• Step 3.6 - Subdivision Updates
• Step 3.7 - Childrens Matching
• Step 3.8 - MESH Matching
• Step 3.9 - Canadian Matching
• Step 3.10 - Local Bibliographic Subject Matching
• Step 3.11 - Genre Form Matching
• Step 3.12 - Local Fields in Authority Records
• Step 3.13 - Local Authority Master
• Step 3.14 - JACKPHY Vernacular
• Step 3.15 - Pseudonyms
• Step 3.16 - Deblinding XRefs

The rest of the information contained in Step 3 details the matching options for your bibliographic and authority records. As with each step of this profile, these options are suggestions though each one can be customized according to your preference.

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