Quick overview of authorities

Quick overview of authorities

Quick overview of authorities

Supports a controlled vocabulary for names, subjects, and titles
- Also floating subdivisions (form, chronological, geographical, general)
Implemented as a separate set of MARC records, with one authorized heading per authority record
Each authority record can include tracings
- See reference leads from an unauthorized heading to an authorized heading
- See also reference leads from one authorized heading to another authorized heading
As authorized heading evolves over time (Cookery → Cooking, or addition of death dates to names), changes should propagate automatically from authority record to bibliographic records using that heading

Authorities in Evergreen 1.x

Features:
- Import and forget
- MARC editor: Validate button and context menu
- Search assistance (facets)
Limitations:
- No way to edit or delete authority records
- No linkage between authorities and bibs
- No way to search authorities
- No way to publish authorities

Authorities in Evergreen 2.0 / 2.1

Features:
- Import, edit, and delete authorities
- Bibs are linked to authority records instead of just string matches
- Edits to authority records automatically apply to linked bibs
- MARC editor: select and apply, including see from and see also entries
- Duplicate authorities are prevented by default
- Search and publish authorities via SRU and Z39.50 (2.1)
Limitations:
- Controlled fields are hard-coded
- No linkage between authorities (4xx see from, 5xx see also, 7xx reciprocal entries)
- Floating subdivisions are just another subfield
- No real concept of thesauri (LCSH vs. MeSH vs. LAC)

Getting authorities into Evergreen 2.0 / 2.1

Largely unchanged since 1.6.x; two options:
- MARC Batch Import: best for batches of 5,000 records or less
- marc2are.pl script: best for bulk loads

Don’t fear the command line: import

perl marc2are.pl --user admin --pass secret authorities.mrc |
    perl pg_loader.pl --auto are --order are |
    psql -U evergreen -h localhost -d evergreen

Advantages:
- Fast - no overhead
- With piped input, uses parallel processing
Disadvantages:
- Requires command-line and database access

Managing authority records

Once authority records have been loaded, the Cataloging → Manage Authorities menu entry becomes useful

Editing an authority record

Actions → Edit opens the authority record in a MARC editor:

Editing an authority record: result

Merging authority records

Action → Merge enables you to merge two or more authority records
Bibliographic records are linked to the master authority record

Controlling fields manually

Fields in bibliographic records that are controlled by an authority record will be linked via a ‡0 subfield per MARC rules
Right-clicking a field in the MARC Editor triggers an alphabetical browse of available authority records, including 4xx and 5xx matches
Ability to create an authority record on the fly

Browsing authority records

The classic MARC editor offers an authority browser on controllable fields

Browsing authority records (raw)

Browse interface exposes MARCXML records to the Web
- Template: http://hostname/opac/extras/browse-type/marcxml/index/scope/term/page/per-page
  - browse-type can be browse to place closest match in the middle of results, or startwith to place closest match at start of results
  - index can be authority.author, authority.subject, authority.title, authority.topic to search 1xx ‡a
    - .refs index variants such as authority.author.refs include 4xx and 5xx fields in the search criteria
  - scope is effectively always 1 (entire consortium); authority records have an owning library, but no interface is exposed to manipulate that
  - term is the string to match against the ‡a field
  - page is the page of results to display; this can be a positive or negative integer
  - per-page is the number of results to display per page
Example: http://hostname/opac/extras/browse/marcxml/authority.title.refs/1/rowling/0/10

Authority search / browse indexes (2.0/2.1)

Authority categories map to main entry fields as follows:
- Author: 100‡a, 110‡a, 111‡a
- Subject: 148‡a, 150‡a, 151‡a, 155‡a
- Title: 130‡a
- Topic: 150‡a
When you launch the authority browser from a bibliographic field, the bib field’s tag is replaced with a 1 and the browse is launched according to the preceding categories
- For example, the editor converts 100, 600, 700, 800 to 100 and an author browse is launched
- More sophisticated mapping exists, covering the case of bib 240 to auth 130, but is not currently in use

Controlling uncontrolled bibliographic records

A script is available to link bibliographic records against authorities
De-duplicate your authority records first (you’re on your own for that)
This script is slow; run it in parallel against subsets of your database:

perl authority_control_fields.pl --start 1 --end 50000
perl authority_control_fields.pl --start 50001 --end 100000
perl authority_control_fields.pl --start 100001 --end 150000

Slow = ~4 days to control 1,000,000 records with no parallelism on our slow test server

Controlling every subfield in a field

Controlling everything other than subfield 0 is a simple matter of changing /openils/var/web/xul/server/cat/marcedit.js:

/* Filter out subfields that are not controlled for this tag */
if (!control_map[source_f.tag][sf_iter.@code.toString()]) {
    continue;
}

to:

/* Filter out everything except for subfield 0 */
if (sf_iter.@code.toString() === '0') {
    continue;
}

Publishing authorities

As of Evergreen 2.1, authorities will be exposed via SRU with the following indices:
- id: the numeric ID of the authority record
- author: browses name headings (100, 110, 111)
- subject: browses all subjects (148, 150, 151, 155)
- title: browses uniform titles (130)
- topic: browses just topical terms (150)
Example: http://localhost/opac/extras/sru_auth?version=1.1&operation=searchRetrieve&query=author%3Dwill browses the author index for entries beginning with will
- Limitation: as there is no all index for all authorities, simple queries that do not define an index currently fail
SRU leaves us just one step away from offering a Z39.50 server, thanks to Simple2ZOOM

Modifying field/subfield control maps sanely

Mike Rylander has a set of patches in the works that define field/subfield control sets in the database, rather than in code
- Still needs a configuration interface for modifying the defaults (although the current defaults are much more extensive)
- Still needs to be hooked into the MARC Editor interface
- Likely landing point will be Evergreen 2.2
Limitations in 2.2 (currently):
- No linkage between authorities (see from, see also, reciprocal entries)
- Floating subdivisions are still just another subfield
- No real concept of thesauri (LCSH vs. MeSH vs. LAC)