Authority control in OPAC

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Introduction: The story of catalogue and cataloguing is one of the aspects of the broad panorama of library development. Earlier, libraries concentrated their efforts on the collection and preservation of manuscripts. Later, after the invention of printing, libraries started collecting and organizing materials, which would be kept for reading, study and consultation. For easy location and consultation, librarians and libraries used some system of bibliographical organization or control over the reading materials. This bibliographical organization, in the context of library, is called library catalogue.

S.R. Ranganathan’ defines library catalogue as “a list of documents in a library or in a collection forming a portion of it.” It implies three concepts of library catalogue, i.e., (i) list, (ii) document, and (iii) holding. In 1876, Charles Ammi Cutter clearly defined the objectives of library catalogue. The objectives are as follows.

“1) to enable a person to find a book of which

a) the author or,

b) the title or,

c) the subject is known.

2) to show what the library has

d) by the given author,

e) on a given subject,

f) in a given kind of literature.

3) to assist in the choice of a book

g) as to its edition,

h) as to its character”

The objectives put forward by Charles Ammi Cutter is still being quoted even though the physical form of library catalogue has changed from card format to electronic format, i.e., Online Public Access Catalogue (OPAC). The advent of computer and communication technology has drastically changed the arena of cataloguing. A computer itself can also be used as a catalogue i.e., the information can be stored within the computer and kinds of entries required can be re-produced as when required.

Cutter’s objectives of catalogue have remained constant, even while the means of achieving them have changed with the evolution from book, through card, to online catalogue. Cutter’s objectives were largely adopted as the functional framework for formulating the set of cataloguing principles known as “the Paris Principle” that emerged from International Conference on Cataloguing Principles (ICCP) held at Paris in 1961. The ICCP described the functions of a library catalogue in the following words:

“The catalogue should be an efficient instrument for ascertaining

1. whether the library contains a particular book specified by

a) its author and title, or

b) if the author is not named in the book, its title alone, or

c) if author and title are inappropriate or insufficient for identification, a suitable substitute for the title; and

2.    a) which works by a particular author and

b) which editions of a particular work are in the library.”

The second objective put forward by Cutter and the second function of catalogue described by ICCP implies the importance of collocation function. Collocation function means bringing together all the entries having same heading in a catalogue. If author uses variant names, cross-references are needed to connect his/her variant names.

The selection of one form of heading as entry heading and creating cross-references from other headings was the usual practice of the cataloguer. In the days of book and card catalogue, the cataloguer maintained a record (authority record) of their decision for the standard form of a heading and the variant forms for which cross reference entries were made. These records were mainly needed for larger catalogue and cataloguing units to maintain consistency among multiple cataloguers. The authority control helped the cataloguer to prepare entries of all the works of an author under one standard form of name and provide references to this form of name from variant forms. This procedure saves the time of the users since he can get all the works of an author under one standard form of heading. The reference directs him to this heading from variant forms of names.

The authority records documented the catalogers’ authority work. Authority work consists of “the creation of authority records, the formation of such records into an authority file, the linking of that file to the bibliographic file to form a system, the maintenance of the authority file and system, and the evaluation of the file and system.

Authority control of a library catalogue is maintained through an authority file that contains the terms used as access points in the catalogue. The access points that determine the structure of the catalogue may be real entry headings on bibliographic records or cross-references. In-library catalogue, the entry headings under control generally consists of personal and corporate names, uniform titles, series and subjects.

Authority control can provide:

a) consistency which is particularly important if a library obtains its cataloguing from many different sources;

b) collocation of records with the same access points which in turn helps in the formulation of effective search strategies resulting in good information retrieval;

c) cross-reference structure showing relationships among controlled headings and

d) local policy on standardization of headings which contributes to the overall utility of the catalogue.

On the cataloguer’s perspective, the functions of authority control are:

a) Authority function:- like systematic organization, libraries want to establish consistency in the nomenclature used in their catalogue. Achieving this consistency is extremely time consuming and requires highly trained staff;

b) Finding function:- taxonomist refer to different spellings, synonyms, homonyms hierarchies and so on. The idea is to record these somehow, and link them to authorized nomenclature. Cataloguers do the same thing when they provide references from variant or related forms of a name;

c) Information function:- authority records usually contain documentation about the sources to establish the name or subject heading, and

d) Maintenance function:- authority data is also used to support the detection and correction of errors in library catalogue.

Authority Control in the Card Environment:

Learning about authority control in the card environment gives a better understanding of authority control principles, which can be applied to the automated environment.

Examples of a name authority in card environment; (Choices and forms of entry for names are based on rules set forth in AACR-2)

Key to an Authority card

x = Make See reference from

xx = Make See also reference from.

Authority record Card

Authority record in Card Catalogue
Figure 1.1: Format of Authority Control Record

Authority control in the Automated Environment:

Authority control is used to establish standardized key access points and references to ensure effective access to library catalogue. In the automated environment, MARC records are created for authorities and serve the same function as in the card environment. Authority record in MARC format has one fixed field that contains coded information and many variable fields that usually contain textual information.

For example,

0xx : Call numbers , control numbers

1xxs: Established headings

260: Complex See Reference (Subject)

360 : Complex See also Reference (Subject)

4xxs: See Reference

5xxs: See also Reference

6xx: Notes, series treatment information.

7xx: Heading linking entries.

Online Public Access Catalogue:

ALA Glossary defines OPAC as “A computer-based and supported library catalogue (bibliographic databases) designed to be accessed via terminals so that library users may directly and effectively search and retrieve bibliographic records without the assistance of human intermediary such as a specially trained member of library staff”.

According to Gorman, OPAC is ” a bibliographic control system that allows access by means of access points conventional and unconventional, single and combinational form. The data retrieved is displayed on a terminal screen or printed out on demand. Terminals are housed in the library or elsewhere.”

So, OPAC is an access tool and resource guide to the collection of a library or libraries, which provides bibliographic data in machine-readable form and can be searched interactively on a computer terminal by users. Any OPAC should have some of the qualities given below:

a) OPAC is a bibliographical control system;

b) It allows search by a number of access point to the bibliographic data stored in machine-readable form;

c) It provides instrumental help;

d) It displays the search result in relatively understandable form, and

e) It is an interactive information retrieval system.

OPACs began to appear in libraries in the early 1980’s. Many OPACs represent a radical departure both from card catalogue and from offline computerized catalogue in their implication for the users. Current advances in computer technology and distributed networking have contributed to a surge of interest in the development of a new generation of OPACs that are ultimately intuitive and require a minimum of instruction. Remote access through the Internet, the client/server model, and standards such as NISO, Z 39.50 has opened new doors for vendors and researchers to propose innovative OPACs.

The World Wide Web (WWW) developed as a hypertext and multimedia retrieval system for distributed information that has emerged as the most popular information delivery platform on the Internet. The WWW offers the potential to make online catalogues accessible through the use of gateways.

The expansion of the WWW since early 1990 has been truly amazing. It appeared as a simple communication medium for scientists and researchers; its many and pervasive tentacles have spread deeply into various organizations and homes around the world. By the result, our OPAC has been automatically being converted to WEB OPAC.

Authority Control in Online Environment (Web OPAC):

The Web environment opens up new uses for authority records and adds new objectives to augment the traditional objectives. Sharing and searching for authority records through the Internet has simplified the creation and maintenance of authority record and reduced the cost of cataloguing of local libraries. Authority record in web environment enabled users to access information in the language, script, and form they prefer, and it works as a link to digital resources such as biographical dictionaries, abstracting and indexing services, telephone directory and other reference sources in the web. With the help of authority records, new integrated library system displays reference information to direct users to authorized form of headings. Web catalogue and associated integrated library system provide the traditional authority control functions of creating and updating authority records and displaying the cross-references but have primarily been seen as a tool for cataloguers.

Cataloguers and others can use the authority file as another reference tool for name variations and information to identify entities and also as a channel for reaching bibliographic record and from there reaching directly to digitized resources. The records in this automated file also enable navigation to related entities.

Transliterated Names and Authority control:

The name authority file links variant forms of a heading to the preferred form of heading to help preparation of cross-references. An author may use different names, or variant spellings may be used for his name due to the transliteration process. Transliteration is the process of formulating a representation of word in one language using the alphabet of another language. The aim of transliteration is to represent the script of a source language by using the letters or symbols of another script, usually in accordance with the orthographical conventions of the target language. By the result, a unique name in one language or culture may have variant spelling in another language. This is a situation similar to that of an author using different names or pseudonyms. In such a situation, the cataloguer should create cross-references from variant spellings (different name) to the preferred heading.

Transliteration has wider applications in daily life. Some are given below:

I. Electronic representation of non-Roman languages on platforms where Operation System support for such languages is not available. For example, texts in such languages as Arabic, Russian or Japanese can easily be stored in a multilingual database and manipulated as if they were a language like English,

2. Entering texts in non-Roman languages using an ordinary keyboard with a system that only supports the American Standard Code for Information Interchange (ASCII) character set,

3. Enables users unfamiliar with the non-Roman alphabet to read texts in that language by converting into the Roman alphabet,

4. Phonemic transcription used for pedagogical purposes, called petrography, enables language learners to study non-Roman languages in the Roman script, and

5. Cross-Language Information Retrieval (CLLR) of proper nouns and other information extraction operations can be performed by entering the transliterated string, which is converted before the search is performed. For example, entering bn ldn (transliteration)or bin ladin (transcription) to search for instances of Bin Ladin in Arabic.

Arabic/English International Transliteration Schemes:

For consistency in transliteration process, the ideal solution would be to have a standard, internationally agreed, system. Several agencies have been proposed, but unfortunately none has been universally accepted. Probably the earliest attempt at standardisation was Deutsche Morgenlandische Gesellschaft proposal, adopted by the International Convention of Orientalist Scholars in 1936. It is the system used in the Hans Wehr Arabic Dictionary. Another standard was agreed in 1971 at a conference of Arab experts in Beirut; and theoretically, at least, accepted by the countries of the Arab League. It has met some resistance, particularly in those Arab countries where French predominates over English. Another remarkable attempt was done by the ALA-LC. The Romanisation Tables adopted by the US Library of Congress and the American Library Association for cataloguing books has found its way into wider academic use. It covers a multitude of languages: there are 54 Romanisation tables for more than 150 languages and dialects written in non-Roman scripts.

However, in practice, the application / usage of international transliteration schemes is totally ignored, or found inconvenient in naming process. Names and naming activities are central to human symbolic and communicative process. To be human is to name and be named. The names of persons have shaped its form by the influence of culture, religion and the society. In the case of Muslims, they use Arabic names, even though they are living outside the Arabian countries. They use regional language to write their name, where the first transliteration process is done. Later, again they transliterate their names into English, for some official purpose. For example, a person born in Muslim family in Kerala possessing Arabic name, at first use Malayalam to write his name, and later transliterate it into English for any official purpose International/national transliteration schemes have no significance in this transliteration process and the problem of variant spelling for a unique name still continues here.

Transliterated Names and Unicode:

Since the advent of Unicode, electronic representation of non-Roman characters is not an issue. As a universal character code set, Unicode provides a unique number to every character used in modern scripts throughout the world. The Unicode Standard is the universal character-encoding standard used for representation of text for computer processing. Versions of the Unicode Standard are fully compatible and synchronized with the corresponding versions of International Standard ISO/IEC 10646. For example, Unicode 4.0 contains all the same characters and encoding points as ISO/IEC 10646:2003. The Unicode Standard provides additional information about the characters and their use. Any implementation, that is conformant to Unicode, is also conformant to ISO/IEC 10646.

Unicode provides a consistent way of encoding multilingual plain text and brings order to a chaotic state of affairs that has made it difficult to exchange text files internationally. Computer users who deal with multilingual text—business people, linguists, researchers, scientists, and others—will find that the Unicode standard greatly simplifies their work. Mathematicians and technicians, who regularly use mathematical symbols and other technical characters, will also find the Unicode Standard valuable.

The design of Unicode is based on the simplicity and consistency of ASCII, but goes far beyond ASCII’s limited ability to encode only the Latin alphabet. The Unicode standard provides the capacity to encode all of the characters used for the written languages of the world. To keep character coding simple and efficient, the Unicode standard assigns each character a unique numeric value and name.

The Unicode standard and ISO/IEC 10646 support three encoding forms that use a common list of characters. These encoding forms allow for encoding as many as a million characters. This is sufficient for all known character encoding requirements including full coverage of all historic scripts of the world as well as common notational systems.

The Unicode standard specifies an algorithm for the presentation of text with bi-directional behavior, for example, Arabic and English. Characters are stored in logical order. The Unicode standard includes characters to specify changes in direction when scripts of different directionality are mixed. For all scripts, Unicode text is in logical order within the memory representation corresponding to the order in which text is typed on the keyboard .

The application of Unicode helps to reduce the relevance of transliteration up to an extent. However, transliteration is inevitable in a database, which is designed to meet the needs of people all over the world. In a database having Arabic names entered in Arabic using Unicode cannot be of use to such people who have no knowledge of Arabic language. It means that Unicode can solve the problem of regional languages, but such a database can be of use only to limited people who know that language. So transliteration of personal names from regional languages is essential to meet the need of international users.

Authority Control versus Access Control:

The access control record is the next generation of the authority record. It may be called as “super authority record” because of the potential it contains for enriched information for indexing. Access control records can be linked both to bibliographic records, to collocate all manifestations of a work, and to other related access control records, to collocate related works. The basic concept behind the access control record is removing both the label and notion of “authority”. While authority control record declare a heading as “authorized” form, access control record links all variations without declaring one heading as authorized form. Access control records allow users to choose their preferred form or name, or to have displayed a default heading. It allows for more flexibility in display. The concept of access control entirely contradicts the whole second part of AACR-2, which is devoted to painstaking rules for how to construct authorized forms of names and titles.

Barhhart puts a hypothetical access control records and compare with authority record as follows:

Format of Authority Record

In the hypothetical access control records, the 100 field switched with 400 field and 1xx field would be considered as “default” display. The 1xx field might not then be same in every catalogue of the same bibliographic record. Each library can fix their “default” heading and non-default form can use as reference.

The idea behind the access control is that an entity can be known by more than one name. An individual is an entity but may be called by different names by different people at different times in life. In the international realm living persons have name representations in many languages and script. The possible solution is that, instead of selecting one form of name as heading, give chance to select one of the heading as default headings according to their interest (local convenience) and give non-default as reference.

As stated earlier, finding is one of the functions of authority control, whatever may be the form of catalogue. Taxonomist refers to different spellings, synonyms, homonyms hierarchies and so on. The idea is to record these somehow, and link them to authorized nomenclature. Cataloguers do the same thing when they provide references from variant or related forms of a name. Information scientists also addressed the same problem. In this connection, it would be very helpful to understand how the task of retrieving variant spellings or mis-spellings of a unique name /entity was solved in modern Information Retrieval Systems.

Original Reference Article:

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