Bibliographic Rank Algorithm

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Alma evaluates the completeness and richness of MARC 21 bibliographic records based on information that includes identifiers, names, subjects, informative LDR and 008 fields, publication details, etc. This is reflected in the Bibliographic Rank, meant to provide a helpful tool for libraries to identify records that may need attention. The new bibliographic rank is displayed in the record view and in the Metadata Editor.

The bibliographic ranking range is between 1 - 120. Generally, records that are ranked higher than 75 are considered good records.

The bibliographic ranking is generated through an algorithm that is further described below.

General Model

This is a two-level approach:

Level 1 - Breadth: The focus here is on coverage: Fields are grouped into categories and where a record has any one of the fields in a category it is given a score according to the importance of the category.
- LOW importance gives 1 point
- MEDIUM importance gives 3 points
- HIGH importance gives 7 points
For example, Subjects category has high importance, so it is assigned a score of 7. Canceled identifiers category is less important, so it has a score of only 1. There are 27 categories. The full list is described below.
Level 2 - Depth: The second focus is on depth. For example, rather than just checking that there is a 6XX field, attention is paid to how many 6XX fields are included.
Depth is relevant only for some of the categories. When a record has such a category, the fields in the category are counted. The number of fields is the depth score of the category.

Each relevant category has a "depth limit" to avoid giving too much weight to having many fields.

The total score is breadth score + depth score.

Categories

The following is the full list of categories. For each category, this information is included:

List of the fields in the category
Importance
Indication if it is relevant for depth, and if so:
Depth limit

#	Category Name	Fields	Importance	Relevant for depth?	Depth limit
1	Canceled identifier	010$z- Canceled/invalid LC control number 020$z- Canceled/invalid international Standard Book Number 022$y/z- Canceled or incorrect international Standard Serial Number 024$z- Canceled/invalid other Standard Identifier. First indicator 0,1,2,3,4,7	LOW	No
2	Classification and Call Number	050 - Library of Congress Call Number 082 - Dewey Decimal Classification Number 060 - National Library of Medicine Call Number 070 - National Agricultural Library Call Number 080 - Universal Decimal Classification Number 083 - Additional Dewey Decimal Classification Number 086 - Government Document Classification Number	HIGH	Yes	3
3	Coded language/place/time	041 Language 042 - Authentication Code 044 - Country of Publishing/Producing Entity Code 047 - Form of Musical Composition Code	LOW	Yes	3
4	Control fields	007	MEDIUM	No
5	008 Common data	One or more of the following, must have value that is not \| nor #: 00-05 (Date entered on file) 06 (Type of date/Publication status) 07-10 (Date 1) 11-14 (Date 2) 15-17 (Place of publication, production, or execution) 35-37 (Language) 39 (Cataloging source)	HIGH	Yes	5
6	008 Books data (If Leader/06 = a and Leader/07 = a, c, d, or m)	One or more of the following, must have value that is not \| nor #: 18-21 - Illustrations 22 - Target audience 23 - Form of item 24-27 - Nature of contents 28 - Government publication 29 - Conference publication 30 - Festschrift 31 - Index 33 - Literary form 34 - Biography	LOW	No
7	008 Computer files data (Leader/06 = m)	One or more of the following, must have value that is not \| and not #: 22 - Target audience 23 - Form of item 26 - Type of computer file 28 - Government publication	LOW	No
8	008 Music data (Leader/06 = c, d, i, or j)	One or more of the following, must have value that is not \| and not #: 18-19 - Form of composition 20 - Format of music 21 - Music parts 22 - Target audience 23 - Form of item 24-29 - Accompanying matter 30-31 - Literary text for sound recordings 33 - Transposition and arrangement	MEDIUM	Yes	5
9	008 Visual Materials data (Leader/06 = g, k, o, or r)	One or more of the following, must have value that is not \| and not #: 18-20 - Running time for motion pictures and video recordings 22 - Target audience 28 - Government publication 29 - Form of item 33 - Type of visual material 34 - Technique	MEDIUM	Yes	5
10	008 Maps data Leader/06 = e, or f)	One or more of the following, must have value that is not \| and not #: 18-21 - Relief 22-23 - Projection 25 - Type of cartographic material 28 - Government publication 29 - Form of item 31 – Index 33-34 - Special format characteristics	MEDIUM	Yes	5
11	008 Continuing Resources (Leader/06 = a and Leader/07 = b, i, or s)	One or more of the following, must have value that is not \| and not #: 18 - Frequency 19 - Regularity 21 - Type of continuing resource 22 - Form of original item 23 - Form of item 24 - Nature of entire work 25-27 - Nature of contents 28 - Government publication 29 - Conference publication 33 - Original alphabet or script of title 34 - Entry convention	MEDIUM	No
12	Edition	250 - Edition Statement	HIGH	No
13	Identifier	010 $a/b- LC control number 020 $a- International Standard Book Number 022 $a- International Standard Serial Number 024 $a- Other Standard Identifier. First indicator 0,1,2,3,4,7 028 $a - Publisher or Distributor Number	HIGH	Yes	10
14	Leader		HIGH	No
15	Names	100 - Main Entry - Personal Name 110 - Main Entry - Corporate Name 111 - Main Entry - Meeting Name 700 - Added Entry - Personal Name 710 - Added Entry - Corporate Name 711 - Added Entry - Meeting Name	HIGH	Yes	5
16	Note	502 - Dissertation Note	LOW	No
17	Bibliography	504 - Bibliography, etc. Note	LOW	No
18	Subjects	One or more of the following, must have second indicator that is 0/1/2/3/5/6/7. If second indicator is 7, the field must have $$2 with a value that exists in Community Zone: 600 - Subject Added Entry - Personal Name 610 - Subject Added Entry - Corporate Name 611 - Subject Added Entry - Meeting Name 630 - Subject Added Entry - Uniform Title 647 - Subject Added Entry - Named Event 648 - Subject Added Entry - Chronological Term 650 - Subject Added Entry - Topical Term 651 - Subject Added Entry - Geographic Name 655 - Index Term - Genre/Form	HIGH	Yes	15
19	Other Physical information	344 - Sound Characteristics 345 - Moving Image Characteristics 346 - Video Characteristics 347 - Digital File Characteristics 348 - Notated Music Characteristics 310 - Current Publication Frequency 321 - Former Publication Frequency 382 - Medium of Performance 384 - Key 362 - Dates of Publication and/or Sequential Designation	MEDIUM	Yes	3
20	Physical description	• 300 - Physical Description • 336 • 337 • 338	MEDIUM	Yes	5
21	Publication details	• 260 - Publication, Distribution, etc. (Imprint) • 264 - Production, Publication, Distribution, Manufacture, and Copyright Notice	HIGH	No
22	Related items	One or more of the following. Must include $a or $t: • 773 - Host Item Entry • 776	LOW	No
23	Series	One or more of the following. Must include $a: • 490 - Series Statement • 800 - Series Added Entry - Personal Name • 810 - Series Added Entry - Corporate Name • 811 - Series Added Entry - Meeting Name • 830 - Series Added Entry - Uniform Title 780 - Preceding Entry 785 - Succeeding Entry	MEDIUM	Yes	3
24	Summary	• 520 - Summary, etc	MEDIUM	No
25	Table of content	• 505 - Formatted Contents Note	MEDIUM	No
26	Title	• 245 with a minimum of either $a or $k	HIGH	No
27	Uniform title	• 130 - Main Entry - Uniform Title • 240 - Uniform Title • 730 - Added Entry - Uniform Title	LOW	No

Validations

In addition to breadth and depth scores, some Alma validations are done to check the basics of the MARC21 format. The following validations are invoked:

Mandatory fields exist (LDR and 245)
Control fields have legitimate data
Indicators have legitimate data
Only fields that are repeatable appear multiple times
Only subfields that are repeatable appear multiple times
All sub-fields are valid according to MARC standard

If there is an issue, the total score is reduced by 1 point.

Accuracy

In addition to the above validation, there is a check to make sure the data is accurate:

ISBN check digit
ISSN check digit
"Other Standard Number" check digit
Form of material in 006 field (position 0) matches the material type in the leader (LDR)

If there is an issue, the total score is reduced by 1 point.