DATE: May 30, 2002
NAME: Dealing with FRBR Expressions in MARC 21
SOURCE: Joint Steering Committee for the Revision of AACR, Format Variation Working Group
SUMMARY: This paper describes the work of the Joint Steering Committee's Format Variation Working Group to facilitate expression-level collocation in online systems, and discusses possible approaches to achieving this collocation using the MARC 21 Holdings, Bibliographic and Authority Formats.
KEYWORDS: Expression-level collocation; FRBR
RELATED: 2002-DP04 (January 2002), 91-13 (July 1991)
05/30/02 -- Made available to the MARC 21 community for discussion.
06/17/02 - Results of the MARC Advisory Committee discussion - Participants agreed that FRBR is a conceptual model of the relationships between bibliographic items in library catalogs that could be useful to both librarians and library users. There was, however, some confusion expressed over the difference between a work and an expression that participants felt should be resolved. Participants also felt that authority and holdings data should be investigated to ascertain where expression and manifestation data could be found. Although many participants expressed enthusiasm over the perceived improvements that FRBR displays may have on library catalogs, it was also acknowledged that most MARC 21 records are for single works with single manifestations. It is important that there be no adverse impact on them. Whether any refinements to any of the formats will be necessary to accommodate FRBR displays being discuss is not yet clear.
This paper contains a brief summary of the Working Group's current activities, followed by a comparison of several possible approaches to handling expression-level data in MARC 21. Several of these ideas have been presented elsewhere and by others (such as in DP04), and we have gathered them here to facilitate comparison.
Our work is still in progress and it is too soon for us to offer any specific recommendations for changes to MARC 21. However, we are far enough along to suggest to MARBI that a combination of different implementation solutions may be necessary in order to address adequately all situations related for format variation. We have posed several specific questions at the end of this paper related to this in an attempt to facilitate discuss in this area.
The Format Variation Working Group's work is focused upon the bibliographic entity expression, which is defined in the IFLA Functional Requirements for Bibliographic Records (FRBR) as "The intellectual or artistic realization of a work" The entity expression is not currently articulated as such in AACR, nor does it currently have a clear "home" within the MARC 21 formats. Tom Delsey's recent Functional Analysis of the MARC 21 Bibliographic and Holdings Formats illustrates the complexities that currently exist in the formats regarding the entity expression as well as the other FRBR entities of work, manifestation, and item (See Note #1). In Appendix A of his analysis, Delsey shows that while most data associated with the entity expression now appears in the bibliographic format, certain expression-level attributes (namely data frequency and regularity) currently appear in the holdings format. While the Delsey analysis does not discuss the authority format, it is clear by extrapolating the data in that study that some expression-level data (e.g. language of uniform title) now also appears in the MARC 21 Authority Format.
While on the one hand this current situation, where expression-level data is spread between the authority, bibliographic, and holdings formats, complicates discussions of how the MARC 21 formats can best facilitate use of expression-level data, it also provides us with an opportunity to look at several possible approaches. In this paper we present general descriptions of how the various MARC 21 formats may offer potential solutions to the problem of format variations. We hope that MARBI members will take this opportunity to comment on these ideas in a manner that will help to inform our future work in this area.
The CC:DA 0.24 Task Force report presented several options for rewording AACR Rule 0.24 to deal with format variations. Of the options in the report, CC:DA recommended the Task Force's "Option C" to the JSC as one starting point for further discussions of the issues concerning format variation or multiple versions with respect to further revision of rule 0.24 (See Note #2). Specifically, Option C of the 0.24 Report was to:
|"Ignore any mere physical variation or any mere variation in distribution (i.e. any manifestation variation) in determining when to make a new record, " (See Note #3)|
The 0.24 Task Force report then described five data models that could be used
for handling expression-level records, and which the Format Variation Working
Group then used as the starting point of our discussions. (The original models
from the CC:DA 0.24 report are reproduced as Appendix A of this paper).
The Working Group began by using cataloging exercises to test the 0.24 data models. Several Working Group members had immediate difficulty determining how to assign data elements to the expression level. For example, members were concerned about how to determine (or construct) a title for the expression based only upon information from the manifestation in hand. While it is tempting to attribute such difficulty to the unfamiliarity of the task at hand, much of the real difficulty in this case was the lack of information about the expression available to the cataloger from simply examining the manifestation being cataloged.
From this exercise, Working Group members quickly concluded that it is contrary to the way most catalogers work to actually start the cataloging process by cataloging (that is, creating a bibliographic description for) an expression (See Note #4). It is also contrary to the way most library technical services departments operate to begin the cataloging process at the expression level. Rather, it is usually the acquisition of a particular manifestation (a book, an electronic resource, etc.) by a library that triggers the need to create a catalog record for that particular manifestation.
An impressive network of shared cataloging has been created over time by combining the contributions of libraries of all sizes and types, each contributing records for material in hand (i.e. manifestations) following common rules (See Note #5). These records have proven to be compatible precisely because the cataloging rules focus first on describing the material in hand on its own terms, recording titles, statements of responsibility, publication statements, series statements, all attributes of the manifestation, as found. This allows the cataloger, with a minimum of research, to produce a record that library users and library staff in other libraries can with confidence match with citations, for a variety of purposes such as acquisitions, interlibrary loans, or to identify as a basis for copy cataloging. Only once the description is created does the cataloger consider the content in an abstract way, to assign access points, including subject access.
Although the FRBR entities manifestation and item are concrete, the entities work and expression are often only discovered by a process of extrapolation based upon comparing similar manifestations. The boundary of the expression can be open to interpretation, and as more manifestations of a work are created over time, the understanding of their relationships can change, possibly requiring a reassessment of which manifestations belong to the same expression. In a situation where the catalog record is based on identifying the expression, recording the data pertinent to (i.e. "cataloging) a new manifestation would require revisiting and revising the existing catalog record for the expression. This is a more complex--and potentially more expensive--process than our current practice of creating a new record for the manifestation.
Delsey's functional analysis helps to elucidate another problem that the Working Group members found last year in attempting to "catalog an expression." In Appendix B of his report, Delsey maps the attributes of an expression to the MARC 21 Bibliographic and Holdings fields that are defined to contain that data. If one compares that table to Table 1.2 in Appendix D in his report (which lists these attributes) it is clear that of the 30 expression-level attributes defined in FRBR, exactly half of them do not have a specific MARC 21 tag defined to contain them. Some additional expression-level attributes may be included in a catalog record in non-specific textual fields (such as general notes). However, the lack of specific tags for so many of these data elements in the MARC 21 formats confirms our experience that the traditional cataloging process has generally not been focused upon recording expression-level attributes.
The Working Group concluded that while thinking about cataloging at the expression-level may be intuitive for catalogers in some specific settings (such as archives), it is neither logical nor practical as a starting point for most library cataloging. It may be a more viable option in archival collections, particularly when providing access to collections of unique materials. Based upon this, we then rejected those options in the CC:DA 0.24 report (Options 1-4) that describe the creation of expression-based, instead of manifestation-based, catalog records.
While rejecting the general notion of cataloging an expression, the Working Group nevertheless affirmed the value of collocation at the expression level in catalog displays in order to provide additional guidance to the users of our catalogs. In our first Interim Report to the JSC, (www.nlc-bnc.ca/jsc/forvarwg3.pdf) we recommended that our Charge be altered to focus upon the latter: facilitating expression-level collocation of separate manifestation-level records. This approach is represented by Option 5 of the original data models in the 0.24 Working Group, and also is mentioned by the Library of Congress in its action plan for bibliographic control of web resources:
|2.4||Define functional requirements for systems that can manage separate records for related manifestations at the global level and consolidate them for display at the local level. Communicate the requirements to the vendor community and encourage their adoption.|
In our initial interim report, we also described a possible table structure that could be used to link manifestation records at the expression level. We have now further refined the table structure model and, in the options discussed below, have tried to relate it to the existing MARC 21 formats.
During the past six months, under a new charge from the JSC (http://www.nlc-bnc.ca/jsc/forvarwg1rev.html), we have been working on specific changes to AACR to accommodate expression-level collocation. As a part of this, we have been considering how best this collocation might be achieved in the MARC 21 world. This has necessarily taken us away from thinking about how a single record might be displayed and toward thinking about how relationships between records can be displayed in an intelligible way in index displays.
The following is a summary of how various MARC 21-based solutions might facilitate the collocation of expression-level data. We have deliberately not included actual examples for any of these situations for three reasons:
|III.1||The bibliographic record contains only data common to all manifestations (0.24 Options 1 and 3) with data that varies recorded in a Holdings or other type of subrecord.|
|The bibliographic record contains data for all manifestations in repeatable fields, if necessary. (0.24 Option 2)|
|The bibliographic record for one manifestation is allowed to "stand in" for the bibliographic data of the other manifestations, with data that varies for other manifestations appearing in Holdings or other subrecords. (0.24 Option 4)|
The following are some descriptions of these approaches:
|III.4||(CONSER Single-Record Technique). The bibliographic record for one manifestation is allowed to "stand in" for the bibliographic data of the other manifestation. The bibliographic record for the print serial is edited to note the availability of the electronic version, and to include an 856 field to access the electronic version. While the CONSER technique does not specifically describe the use of the Holdings Format, libraries who use this technique may attach holdings records for both the print and electronic manifestations to the same bibliographic record so that this approach ends up looking like III.3 (above). Like the other variants on the single record approach, the CONSER technique is applied only in cases where the bibliographic description for one manifestation can be used for the other manifestation as well.|
|130||0#||$a Bible. $p N.T. $l English. $s Authorized|
The Working Group is currently working on incorporating additional rules into Chapter 25 that will allow for the creation of a heading for other types of expressions as well, should a library decide that it is desirable. If changes to AACR such as these are approved, it is logical to begin looking for ways that the authority format might accommodate these headings. Just as work-level authority records are currently used to collocate headings at the work level, expression-level authority records could be used to collocate headings at the expression level.
At this stage in our work, several things are undeveloped. For example, we haven't determined what such a heading would be called: Expression-level uniform title? Expression-level heading? Expression-level citation? The Working Group has also not yet determined exactly what such a heading/citation for an expression would look like or how it would be formed. While it is tempting to think in terms of stringing additional wording onto the end of a work uniform title to differentiate an expression, there will be times when this model might become cumbersome and confusing for catalogers.
Another possible model would be to think about an existing work heading used in conjunction with one or more other data elements (such as a name heading for a translator or an edition statement) to differentiate one expression from another. These other data elements could be added to the authority record for the expression, rather than stringing the data onto the end of the heading. In this case, a bibliographic record that matches on ALL of the relevant expression-level fields in the expression-level authority record would be identified by the system as a manifestation of that expression.
Some additions to the authority format would be needed to accommodate records for expression-level headings. An additional code might be needed in either the Leader or the 008 to distinguish these records from records that represent other entities (works, persons, etc.). Additional fields would need to be added for other expression-level data, and a mechanism for doing this would need to be determined. However, there is room in the authority format for such additions as, for example, 8XX fields.
Because the creation and use of these records would be optional, the cost for implementing this approach, for a library that chooses to do so, would be kept to a minimum.
Format variation is a complex problem. When it was discussed ten years ago as "multiple versions," it was clear that different interest groups had different concerns. They still do. A solution that works well within a single system may not scale well in a shared database or utility, especially when records need to be communicated. A small public library and a large research library may have very different needs for distinguishing between manifestations. Luckily, we have several tools at our disposal now that we didn't have ten years ago: the FRBR conceptual model and more system options.
If a library or archive needs an inexpensive solution to managing reproductions and other bibliographically similar manifestations, a single-record solution may be very desirable. However, we believe that this approach is not scalable to handle ALL instances of format variation on its own. Therefore, it may be helpful to think in terms of several levels of solutions to this problem, as follows.
Question 1: Could a single-record approach be combined, in the same online system, with expression-level authority records that would provide additional collocation of manifestations of the same expression that are cataloged on separate bibliographic records? This might be of interest to libraries that have already cataloged their materials in a variety of ways. (e.g. some CONSER single records, some separate records).
Question 2: Could an approach based upon bibliographic linking fields to link expressions coexist in the same system with a single-record approach? This might be an attractive option for a library (perhaps with a smaller collection) that is not interested in creating authority records for expressions but would still like to link expressions in cases beyond what is possible using only a single-record approach.
Question 3: Could a linking subfield be used somewhere in a bibliographic record (such as in a field for an expression-level heading) that would explicitly link it to an expression-level authority record (perhaps linking on the authority record number)? This would combine some elements of the bibliographic linking approach with that of the authority-based approach. It could potentially allow linking of expressions in situations when a cataloger knows that two manifestations represent the same expression but when it is either difficult to construct an intelligible expression-level heading/citation or when a cataloger chooses not to do so.
Question 4: Assuming that explicit linkages to expression-level authority records are possible (as described in Question 3), could a mechanism be created in the authority format that would allow for the coexistence of multiple expression-level authority records with the same heading string, but that do not represent the same expression (as opposed to our current method of creating authority records for undifferentiated headings that may represent more than one person, etc. in a single authority record)? A cataloger could then add textual data to the authority record (e.g. Field 667) to explain the relationship between the two expressions. In this situation the authority record, and the explicit linkages to it in bibliographic records, would function primarily as a linking device, like the Table of Reference that the Working Group described in our first Interim Report.
Question 5: Could such a system of explicit linkages be used for linking serials at the expression level, possibly making use of the ISSN? In this case, would it be better to add the authority record number (a system-supplied sequential number) as an explicit link inside the bibliographic record for each manifestation, or would it be more meaningful to put the ISSNs of each serial manifestation into the authority record itself?
There are several possible record structures that might underlie the 'single-record approach' to format variations that is recommended in Option C. These include