PLEASE NOTE: This is an archived document! It is of historical interest only and does not necessarily represent current Yale University Library practice. For other archived documents, go to: Archived Cataloging Documentation. For current documentation, go to: Cataloging at Yale.

Retrospective Conversion Planning Committee
Authority Control Report

Excerpt from a report to LMC dated: 10 July 1995


Authority control is a critical component of the retrospective conversion process. It ensures that the headings (names, series, subjects, and uniform titles) on converted records are consistent with other headings in the catalog and that those headings conform to current national standards. Optimal return on an investment in retrospective conversion requires a parallel investment in authority control.

Like retrospective conversion, authority control can be contracted to a vendor or it can be accomplished in-house. We have carefully considered both of these options, and we have done so in a context that extends considerably beyond the scope of our retrospective conversion project. In particular, we defined the authority control needs of the Library as having three essential dimensions: First, we need to update and correct headings on bibliographic records in the existing Orbis database, generate associated authority records, and eliminate unwanted authority records; Second, we need to update and correct headings and generate associated authority records for bibliographic records created during the retrospective conversion process; and Third, we need to update and correct headings and generate associated authority records for bibliographic records created during the course of current and ongoing cataloging.

Only by responding to each of these three needs can we achieve a comprehensive solution to authority control -- one that will meet the demands of a large retrospective conversion project and, at the same time, fulfil our ongoing need to ensure that all of the headings in our catalog conform to current national standards. We considered several in-house and vended options for each objective. Our recommended strategy is a multi-faceted, primarily vended approach, to authority control that will meet our needs and, at the same time, maximize over the long term the significant investment in authority control that we must be prepared to make.

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Several ongoing and recent developments have raised concerns about the integrity of authority control in the Orbis database. These include the considerable growth of the database since its creation in 1989 and the frequency with which both obsolete and erroneous headings as well as complex, policy-driven heading changes are introduced into the database. Large loads of circulation, microform, retrospective conversion, and current cataloging records, which have introduced more than 2 million headings requiring verification and/or correction, have had a significant impact on our ability to maintain a desirable level of consistency in the database.

Our intention has been to maintain control of the database by implementing specific NOTIS programs, including global change, and establishing a local resource file of Library of Congress (LC) authority records. Although both of these have been accomplished, our ability to effectively utilize these resource has been greatly impaired by several factors. First, the database maintenance staff have had to devote virtually all of their attention to the headings generated by a monthly influx of as many as 2,500 provisional circulation records, created "on-the-fly" by circulation staff across the library system. Even more problematic, however, is the current structure of the authority files in the Orbis database. Our best efforts to maintain control are dramatically limited by the fact that the production authority file and the Library of Congress authority file are completely independent of each other. Consequently when heading changes are introduced into the LC authority file, which happens regularly, those changes do not automatically make their way into the production authority file nor do they affect the headings in the Orbis database. Hundreds of changes to headings, many of which are critical to effective use of the catalog by staff and public users, must be made as they are encountered, on a case-by-case basis. This process is hugely time consuming and inefficient and we have been unable to keep up with even the most important changes.

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Our best in-house option for authority control would require combining the LC authority file and the production authority file into a single authority file and then running a monthly batch job that would compare the headings in the bibliographic file to the authority file, activate the appropriate authority records, and update obsolete bibliographic headings to the currently authorized form. Although such an approach to authority control would adequately address our requirements for current cataloging, it is not a practical approach for retrospective conversion nor even a possible approach for correcting and updating the headings on the approximately 2.5 million bibliographic records currently in Orbis, which can only be processed by a vendor. Moreover, it would require significant programming effort, most of which would not readily migrate to a new system should such a change be required. We compared both the costs and the implications of this approach to the costs and implications of vendor-contracted authority control which, like vendor-contracted retrospective conversion, has a number of advantages that distinguish it from even the most creative in-house solution.

The authority control services that are currently offered by several vendors range from those that provide routine batch processing of a library's bibliographic records against the Library of Congress authority files to those that offer more customized options for record processing and delivery. At the most basic level, vendor-contracted authority control is a four-part process involving file preparation and preprocessing, authority file matching, authority record generation, and provision of corrected bibliographic records and associated authority records. Most vendors also offer a notification service, by which updates to those authority records that the library has already received from the vendor are sent, thereby affording the contracting library the opportunity to address their ongoing authority control needs and the means to maximize their initial investment in authority control.

For retrospective conversion, vendor-contracted authority control is usually a relatively straightforward option, because the records can simply be processed (by the retrospective conversion vendor) or sent (to a different vendor) for authority control processing before they are loaded into the library's database. Since the records are new to the database, the problems that often arise with replacement records, which usually require that the database remain static while authority control processing is taking place, are not an issue. In a broader context, however, where large numbers of current cataloging and other bibliographic records would be regularly and frequently extracted from the database and sent to a vendor for authority control processing, the problems associated with replacement records appear daunting.

The best alternative is to take advantage of the recent availability of transaction records, which include only the record identification number, the text of the old heading, and the text of the new heading. In this way, only the affected field in a bibliographic record is modified, thereby allowing the database to remain completely dynamic while authority control processing is under way. OCLC developed transaction records to meet the demands of the Harvard project, in which thousands of records loaded from the retrospective conversion process as well as current cataloging and other bibliographic records are extracted daily from the database and sent to OCLC for authority control processing. In that context, where enormous numbers of records are in an almost constant state of motion, replacement records were simply not an option. The authority control services provided by OCLC offer several additional advantages over traditional authority control services, the most significant of which is that the OCLC headings correction software relies upon sophisticated algorithms to process complex heading changes, thereby reducing significantly the amount of manual review required.

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In order to ensure that the Orbis database is as current and as error-free as possible before retrospective conversion is underway, we recommend that the Library contract immediately with OCLC to accomplish our first objective -- update and correct headings on bibliographic records in the existing Orbis database, generate associated authority records, and eliminate unwanted authority records.... The following activities are required:

Subsequent steps in the process would be to design and contract authority processes for the recon records and for ongoing cataloging....

Our recommendation for a comprehensive, vended approach to authority control is intended to best meet the demands of a large retrospective conversion project and the demonstrated need for sophisticated, systematic authority control on an ongoing basis. At the same time, the proposed approach will maximize over the long term -- for the Library and for our users -- the significant investment in authority control that is so critical to successful use of our catalog.

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