Relational Models for Aggregates

Ed O’Neill

IFLA FRBR Workshop

Dublin, Ohio, May 2, 2005

OCLC Research

Aggregates

When you focus on one part, it’s hard the see the big picture

There are many incompatible views of aggregates

Aggregates are Common

• Originally published in 1771, it is generally regarded as Smollett’s finest novel

• 48 distinct expressions have been identified

• 274 manifestations in WorldCat

– 190 in single work manifestations

– 78 in aggregates (probably more; many still unidentified)

Focus

• Types of Works

• Granularity (Work or Aggregate)

• FRBR Models for Aggregates

Types of WorldCat Works

• Elemental: Works have only a single manifestation (78 %)

• Simple: Works have only a single expression but multiple manifestations (16 %)

• Complex: Works have multiple expressions (6 %)– Revisions (53%)– Translations (26%)– Aggregates (9%)– Augmentations (2%)

AugmentationsWorks where material has been added without changing the original

The Expedition of Humphry Clinker has been extensively augmented with: notes, introductions, illustrations, bibliographies, glossaries, etc.

This drawing by Hablot Knight Browne was used to illustrate several editions of the Expedition of Humphry Clinker

Revisions

1st (1968) and 2nd (1971) editions are authored by John Phillip Immroth.

3rd (1980) and 4th (1990) editions are authored by Lois Mai Chan and “Immroth’s” was added to the title.

For the 5th (1999) edition, “Immroth’s” was dropped to revert back to the original title.

Works that have been updated

Aggregates

Multiple works combined to form an aggregate

Translations

Works in which all expressions, except the original, are translations

Defining a Work

• Guidelines for identifying the boundaries between one work and another are briefly presented in the Report; Barbara Tillett developed a chart that further clarified these boundaries

• The Report provides little guidance on differentiating between components, works, and aggregates

• Clear guidelines for identifying components, works, and aggregates are a key to developing the full potential of FRBR

Need for Consistency

The Report states that “it is difficult to define precise boundaries for [works]” and that “the concept of what constitutes a work and where the line of demarcation lies between one work and another may in fact be viewed differently from one culture to another.”

This fails to adequately consider the impact of such flexibility in a shared cataloging environment where consistency is essential. Differing definitions of a work will result in multiple entries (duplicates) for the identical conceptual entity.

Universality Principle

If an entity is a work in any of its manifestations, it is a work in all manifestations

•The criteria for identifying a work must be based on the properties of the work

•Since a work is an abstract entity, its properties are independent of its manifestations

Definitions

• Work: The smallest autonomous intellectual or artistic entity

• Aggregate: An entity comprised of multiple works

• Component: A subunit or component part of a work

Criteria

• Has an identity (Author / Title)

• Was created independently

• Can be used autonomously

• Is the typically cited entry

• Is sold, published, or distributed separately

• Has separable rights (Copyright)

A work is the smallest entity that:

Granularity Example

Components

Comprised of

Aggregate

Grouped into

Work

Set of Aggregates

Collected into

3 Models for Aggregates

•Single Work

•Work of Works

•Manifestation of Works

Single Work Model

Aggregate Work

Expression

Manifestation

• Simple, non-recursive

• All aggregates considered to be a distinct work

• Each combination (or permutation) of expressions becomes a new work

• Identity of individual works is lost

• Distinction between the work and the expression is obscured

• Most aggregate works have a single expression; often a single manifestation

Single Work Model

Aggregate Work

Expression

Manifestation

Work of Works Model

Expression

Manifestation

Aggregate

Work

• Highly complex, recursive

• An individual work can be part of multiple aggregates

• Each aggregate or work can have multiple expressions with multiple manifestations

• Few practical benefits

• Successful applications limited to very simple cases

Expression

Manifestation

w1 Robertson Davies’ The Deptford trilogy

w1.1 Robertson Davies’ Fifth business

w1.2 Robertson Davies’ The manticore

w1.3 Robertson Davies’ World of wonders

Work of Works

Report, p. 28

Manifestation of Works Model

Expression

Work

Manifestation

Expression

Work

Manifestation

Expression

Work

Manifestation

AggregateManifestation

• Relatively simple, non-recursive

• Aggregates are primarily physical entities—not abstract

• An aggregate is considered to be a manifestation rather than a work

• Expressions retain their identity in all manifestations

• Identity of individual works is maintained

• Distinction between the work and the expression is preserved

Basis for Manifestation of Works

Work

Expression

Is realized through

ManifestationIs embodied in

Only Many-to-Many Relation

Smollett’s Works

w1 Roderick Random

w2 Humphry Clinker

w3 Smollett’s novels

w3.1 Roderick Random

w3.2 Humphry Clinker

w1 Robertson Davies’ The Deptford trilogy

w1.1 Robertson Davies’ Fifth business

w1.2 Robertson Davies’ The manticore

w1.1 Robertson Davies’ World of wonders

Simplified example of Smollett’s novels

Exp

ress

ion

sM

an

ifest

atio

ns

Wo

rks

Modeling ‘Novels’ as a Work

Novels3

Clinker3.2Random3.1

Clinker3.2.1Random3.1.1

Smollett’s Novels

Novels3.1

? ?

Clinker

Clinker2

Clinker1

Modeling ‘Novels’ as a Work

Novels3

Smollett’s Novels

Clinker3.2Random3.1

Clinker3.2.1Random3.1.1

Novels3.1

Exp

ress

ion

sM

an

ifest

atio

ns

Wo

rks

Random

Random1

Clinker

Clinker2 Clinker1

‘Novels’ as a Manifestation

Smollett’s Novels

Aggregate

Bridge Over Troubled Water

1. Bridge over troubled water

2. El Condor pasa

3. Cecilia

4. Keep the customer satisfied

5. So long Frank Lloyd Wright

6. The boxer

7. Baby driver

8. The only living boy in New York

9. Why don't you write me

10.Bye, bye love

11.Song for the asking

Bridge

Bridge1

Bridge Over Troubled Water

Bridge2

Work1 Work1 Work1 Work1

Bridge3

Bridge4

Recommendations

• Recognize the universality of works

• Define works as the smallest autonomous entry

• Exclude recursive relationships for works

• Treat aggregates as manifestations

The End

Questions,

Suggestions,

Comments,

Discussion

References

• IFLA Study Group on the Functional Requirements for Bibliographic Records. 1998. Functional requirements for bibliographic records: final report. München: K. G. Saur. Also available online at <http://www.ifla.org/VII/s13/frbr/frbr.pdf and at <http://www.ifla.org/VII/s13/frbr/frbr.htm.

• Bennett, Rick, Brian F. Lavoie, and Edward T. O’Neill. 2003. “The Concept of a Work in WorldCat: an Application of FRBR”. Library Collections, Acquisitions, & Technical Services 27: 45-59.

• O’Neill, Edward T. 2002. “FRBR: Functional Requirements for Bibliographic Records: Application of the Entity-Relationship Model to Humphry Clinker”. Library Resources & Technical Services 46(4): 150-159.

• Hickey, Thomas B. and Edward T. O’Neill. (Forthcoming) “FRBRizing OCLC’s WorldCat”, Cataloging & Classification Quarterly.