Definition of Object-Oriented frbr

2. Description of the Model

This section explains the model in context from a functional perspective with the help of a comprehensive graphical representation of all constructs, describes the format conventions for the formal specifications, and lists the complete class and property definitions that make up the model. The graphical representation (section 2.1) serves an overall understanding, while the list of definitions (sections 2.6 and 2.7) is the reference for the individual declarations.

2.1. Graphic Overview of the Object-Oriented Definition of FRBR

In this section, FRBR_OO is presented in a sequence which follows the intellectual process from Work through Expression to Manifestation. In contrast to FRBR_ER, a dynamic view of the respective processes of Expression Creation and of the Publication Work is also presented. Additionally, the dimension of intellectual contributions made by incorporating parts of an Expression in another one is demonstrated using the example of the performing arts. This dimension is only marginally analysed in FRBR_ER. This section then contains a presentation of how FRBR_OO models the process of identifier creation, which does not belong to the scope of FRBR_ER but is an important aspect of FRAD. The section ends with a brief statement about the modelling of photographs and animated images.

2.1.1. Static View of the Work and Expression Classes

Figure 6 shows the relations that exist between works and expressions and the subclasses of both concepts, independently from any dynamic aspects involving the activities of creation and modification. It shows an analysis of the original FRBR_ER concepts Work and Expression into the more detailed ones that appear only indirectly in FRBR_ER via attributes that are specific to these detailed concepts rather than to Work and Expression in general. The reader may find the actual relation of these concepts to the FRBR_ER attributes in section 3.3 below.

Figure

Comments on Figure 6:

1. 
   The concepts that make up a work are realised as complete sets of signs. This fact is modelled as: F1 Work R3 is realised in (realises) F22 Self-Contained Expression.
   
2. 
   A set of signs may not convey the complete concept of a work; it may just be a fragment of a larger set of signs. This fact is modelled as: F2 Expression R15 has fragment (is fragment of) F23 Expression Fragment.
   
3. 
   A complete set of signs may be a structural part of a larger set of signs. This fact is modelled as: F2 Expression R5 has component (is component of) F22 Self-Contained Expression.
   
4. 
   A work can present itself as a “continuation” of some other work. This fact is modelled as: F1 Work R1 is logical successor of (has successor) F1 Work.
   
5. 
   A work can present itself as “derived” from another work, in many possible ways. This fact is modelled as: F1 Work R2 is derivative of (has derivative) F1 Work R2.1 has type E55 Type [of derivation].
   
6. 
   The notion of “work” is actually a vague one, which covers three more specific notions:
   
   • 
     The sum of concepts conveyed by just one complete set of signs. This is modelled as: F14 Individual Work is a F1 Work, and F14 Individual Work R9 is realised in (realises) F22 Self-Contained Expression.
     
   • 
     The concept of re-using some already existing material in order to produce some new creation. This is modelled as: F16 Container Work is a F1 Work, F1 Work R3 is realised in (realises) F22 Self-Contained Expression, and F22 Self-Contained Expression P165 incorporates (is incorporated in) F2 Expression.
     
   • 
     The conceptual unity observed across a number of complete sets of signs, which makes it possible to organise publications into “bibliographic families.” This is modelled as: F15 Complex Work is a F1 Work, and F15 Complex Work R10 has member (is member of) F1 Work.
     
7. 
   Additionally, a work can be recognised as being composed of several structural parts. This is also modelled as: F15 Complex Work is a F1 Work, and F15 Complex Work R10 has member (is member of) F1 Work.
   
8. 
   Works that re-use some already existing material or use some event, either natural or involving human activity (i.e., instances of F16 Container Work), are further subdivided into:
   
   • 
     Works that aggregate already existing expressions of other works. This is modelled as: F17 Aggregation Work is a F16 Container Work, F17 Aggregation Work is a F14 Individual Work, F14 Individual Work R9 is realised in (realises) F22 Self-Contained Expression, and F22 Self-Contained Expression P165 incorporates (is incorporated in) F2 Expression.
     
   • 
     Works that consist in establishing all the features of recordings of sounds and/or images (either natural or involving human activity). This is modelled as: F21 Recording Work is a F1Work, F21 Recording Work R13 is realised in (realises) F26 Recording, and F26 Recording is a F22 Self-Contained Expression.
     
   • 
     Works that consist in establishing all the features of a performance. This is modelled as: F20 Performance Work is a F16 Container Work, F20 Performance Work R12 is realised in (realises) F25 Performance Plan, and F25 Performance Plan is a F22 Self-Contained Expression.
     
   • 
     Works that consist in establishing all the features of a publication. This is modelled as: F19 Publication Work is a F16 Container Work, F19 Publication Work R3 is realised in (realises) F24 Publication Expression, and F24 Publication Expression is a F22 Self-Contained Expression.
     
   • 
     Works that consist in establishing all the features of serials are a specific case of the latter; but serials have particular constraints as to their frequency of issuance, numbering pattern, etc. This is modelled as: F18 Serial Work is a F19 Publication Work, and F18 Serial Work R11 has issuing rule (is issuing rule of) E29 Design or Procedure [a CIDOC CRM class].
     

2.1.2. Dynamic View of the Work and Expression Classes

Figure 7 shows the dynamic process through which products of the mind come into being.

Figure

Comments on Figure 7:

• 
  An instance of F1 Work begins to exist from the very moment an individual has the initial idea that triggers a creative process in his or her mind. This is modelled as: F27 Work Conception R16 initiated (was initiated by) F1 Work.
  
• 
  Unless a creator leaves at least one physical sketch for his or her work, the very existence of that instance of F1 Work goes unnoticed, and there is nothing to be catalogued. At least one instance of F2 Expression that R3i realises the instance of F1 Work has to be created. This is modelled as: F28 Expression Creation R19 created a realisation of (was realised through) F1 Work, and F28 Expression Creation R17 created (was created by) F2 Expression. Except for oral tradition and recording in human memory, this very first instance of the respective F2 Expression would be created simultaneously on a physical carrier, typically as a unique item or as an electronic file on a specific computer. This is modelled as: F28 Expression Creation R18 created (was created by) F4 Manifestation Singleton, as detailed in Figures 8 and 9.
  
• 
  Sound recordings and moving images are particular cases of expressions, in that they involve both temporal entities (the “things” being recorded, either performances of works, natural events, or states) and decisions made by one or more than one individual (sound engineer, movie director…). This is modelled as: F29 Recording Event R20 recorded (was recorded through) E5 Event, F29 Recording Event R22 realised (was realised through) F21 Recording Work (i.e., the artistic and technical decisions made about the recording material to be used, the location of microphones and/or cameras, the use of filters, lighting, framing, etc.), and F29 Recording Event R21 created (was created by) F26 Recording (i.e., the set of either analogue or digital signs that are inevitably infixed on a carrier at the time they are produced – just like any other kind of expression – but are likely to be conveyed on any other carrier without losing their identity as a distinct expression).
  
• 
  Publishers make decisions about all the features of a new product, and determine the complete set of signs that will be found on it. This is modelled as: F30 Publication Event R23 created a realisation of (was realised through) F19 Publication Work (i.e., a publisher’s concept of a given publication), and F30 Publication Event R24 created (was created through) F24 Publication Expression (i.e., the set of all the signs present on a given publication, including book cover, title page, page numbers, copyright statement, CD liner notes, text found on a DVD container, etc.).
  
• 
  Performers make decisions about all the features their performance should display (whether it is an improvisation or it involves some pre-existing work such as a play or a musical composition), and may express these decisions as explicit instructions. This is modelled as: F31 Performance (i.e., the performing activity itself) R25 performed (was performed in) F25 Performance Plan (i.e., the set of instructions for a specific performance, which P165 incorporates the text of a play, the content of a musical score, etc.).
  

2.1.3. Dynamic View of the Manifestation and Item Classes

Figure 8 shows how products of the mind are communicated among human beings through physical carriers that eventually become part of the cultural heritage preserved in memory institutions such as libraries, archives, and museums.

F4 Manifestation

Singleton

F28 Expression Creation

R6 carries (is

carried by)

R18 created

(was created by)

F24 Publication Expression

E12 Production

From Expression to Publication

E70 Thing

F2 Expression

F3 Manifestation

Product Type

R4 carriers provided by

(comprises carriers of )

F5 Item

R7 is example of

(has example)

F32 Carrier

Production Event

R26 produced

things of type (was

produced by )

R27 used as source

material (was used by )

R28 produced

(was produced by)

F33 Reproduction Event

R17 created

(was created by)

R29 reproduced (was

reproduced by)

E84 Information

Carrier

R30 produced (was produced by)

P165 incorporates

(is incorporated in)

Figure
Comments on Figure 8:

Authorial output:

• 
  A creator elaborates an expression (it can be a text, a musical score, a drawing, a map, etc.). This process is modelled as: F28 Expression Creation R17 created (was created by) F2 Expression.
  
• 
  The creator externalises that expression by transforming bits of the physical world into physical carriers of his or her creation. This is modelled as: F28 Expression Creation R18 created (was created by) F4 Manifestation Singleton (e.g., a draft manuscript).
  

Editorial product:

• 
  A publisher elaborates the overall content of a new publication: F30 Publication Event R24 created (was created through) F24 Publication Expression (see Figure 2).
  
• 
  That overall content incorporates the authorial expression such as that found, for instance, on a manuscript provided by the author: F24 Publication Expression P165 incorporates (is incorporated in) F2 Expression.
  

Printing/manufacturing:

• 
  The publisher sends to a manufacturer the overall content of the publication (a mechanical or paste-up, or, most often nowadays, desktop publishing files), along with instructions as to how exemplars of the publication should be manufactured: F32 Carrier Production Event R27 used as source material (was used by) F24 Publication Expression.
  
• 
  As a consequence, all exemplars of the publication are supposed to be similar, i.e., can be identified as belonging to the same type: F32 Carrier Production Event R26 produced things of type (was produced by) F3 Manifestation Product Type.
  
• 
  As a consequence, both the author’s expression and the publisher’s expression are to be found on all exemplars belonging to that type: F2 Expression R4 carriers provided by (comprises carriers of) F3 Manifestation Product Type.
  
• 
  The manufacturing process results in physical objects, the exemplars themselves: F32 Carrier Production Event R28 produced (was produced by) F5 Item.
  
• 
  Any exemplar is representative for the publication of which it is an exemplar: F5 Item R7 is example of (has example) F3 Manifestation Product Type.
  
• 
  Under normal conditions, any exemplar should display the same overall content defined by the publisher: F5 Item R6 carries (is carried by) F24 Publication Expression.
  

Reproduction:

• 
  Any information carrier can be reproduced by processes that render a similar item to the original used: F33 Reproduction Event R29 reproduced (was reproduced by) E84 Information Carrier. This should not be confused with resuming the actual production process itself.
  
• 
  This process results in a new instance of E84 Information Carrier: F33 Reproduction Event R30 produced (was produced by) E84 Information Carrier.
  

2.1.4. Static View of the Manifestation and Item Classes

Figure 9 shows how FRBR_OO renders the meaning of the FRBR_ER Manifestation entity and its attributes.

Figure
Comments on Figure 9:

Manifestation is split into F4 Manifestation Singleton (a unique, physical object) and F3 Manifestation Product Type (a publication, i.e., an abstract notion only recognisable through its physical exemplars).

Every time a creator drafts a new expression on paper (or on the hard disk of a computer, etc.), that process results simultaneously in the creation of a new information object and the production of a new physical man-made thing: F28 Expression Creation R17 created (was created by) F2 Expression, and F28 Expression Creation R18 created (was created by) F4 Manifestation Singleton. (Not all manuscripts, however, are necessarily produced by an instance of F28 Expression Creation: a perfect copy of a brief text, made by a highly trained scribe from an original, and checked several times with the original to contain no alteration of the text, could be regarded as just the result of an instance of E12 Production; but as a rule, no two mediaeval manuscripts carry exactly the same text).

Once an authorial expression has been published, the publishing process has created a type of physical objects that carry that authorial expression: F2 Expression R4 carriers provided by (comprises carriers of) F3 Manifestation Product Type.

As an abstraction, a publication cannot be said to have such physical characteristics as the material it “consists of” or its “number of pages”; these physical characteristics are found by a cataloguer on one of its exemplars, and the cataloguer extrapolates this to all other exemplars of that publication which will normally display the same physical characteristics. This is modelled in FRBR_OO as a series of “CLP” properties, i.e., “class properties” or physical properties that apply to an abstract type only through the physical things that exemplify that abstract type: F3 Manifestation Product Type CLP45 should consist of (should be incorporated in) E57 Material, CLP57 should have number of parts E60 Number, etc.

2.1.5. Performing Arts as an Example for the Incorporation of Expressions in Expressions of Other Works

Figure 10 illustrates the way FRBR_OO models live performing arts. In contrast to the other figures, it makes use of a concrete example. It demonstrates how successive intellectual processes incorporate Expressions from previous ones, add new elements of different natures, and thereby “add value” to the previous steps. In this sense, the performance adds movement and sound to a text, the recording adds points of view or ways of seeing.

Figure

Comments on Figure 10:

Shakespeare’s Henry IV is a play in 2 parts: each part is a self-contained play in its own right, but forms nevertheless parts of a larger overall F15 Complex Work.

The text of Henry IV Part 1 is adapted in order to be performed; this process results in a new text, an instance of F22 Self-Contained Expression.

The text of this adaptation is incorporated in the stage director’s instructions for performance, which realise his or her concept of a mise-en-scène of Henry IV.

The play is performed on December 25, 2007.

That performance is filmed.

The resulting recording, which in turn incorporates some aspects of the stage director’s performing instructions, in addition to the adapted text of Henry IV Part 1, is infixed on a DVD.

Similar considerations hold for the contributions of an editor, illustrator and graphics designer to a manuscript, or the compiling of a collection of poems to the texts selected.

Figure 10 demonstrates three fundamental relationships between instances of F1 Work:

• 
  Continuation or completion of a topic (such as Henry IV part 1 and part 2)
  
• 
  Derivation of an existing Expression in an alternative form (such as original and adaptation)
  
• 
  Incorporation of an unaltered part of the contents of an Expression (such as play text and performance recording).
  

2.1.6. Creation and Assignment of Controlled Access Points

During the cataloguing process, one important phase is the creation of what are termed controlled access points (formerly known as “headings”). Controlled access points enable a given instance of a given bibliographic entity to be consistently referred to in a given bibliographic database. Controlled access points are, in general, composed of parts, which consist of signs, and some of which are appellations in their own right. They are created to identify persons, corporate bodies, geographic areas, works, etc.

Specific sections of cataloguing rules specify the steps that have to be followed when creating a controlled access point and how to ensure its uniqueness. The steps include the choice of the preferred form of the name, the choice of qualifiers, their form, punctuation and order. During an F40 Identifier Assignment the cataloguer composes the identifier and makes informed decisions. That complex process is modelled using three distinct classes: F12 Nomen, F13 Identifier, and F50 Controlled Access Point. F13 Identifier corresponds to both standardised strings such as uniform titles (which are instances of F50 Controlled Access Point), and the notion of numeric identifiers such as international standard numbers defined in ISO standards (such as ISNI, ISBN, ISSN, ISRC, etc.). Any qualifier used in cataloguing practice to disambiguate access points is an instance of E90 Symbolic Object (or, in many cases, of its subclass E41 Appellation; e.g., dates are appellations of instances of E52 Time-Span).

Figure 11 is a representation of such an activity.

Figure

The model described in Figure 11 is relevant beyond library practice. It allows for the implementation of the reasoning processes involved in analysing the information encoded in the parts of an identifier. Therefore the CIDOC CRM has incorporated this model.

The process of creating controlled access points that are as specific, accurate, and as “unique” as possible is particularly interesting when applied to instances of Work and Expression, as they lack a material nature. Figure 12 shows how the instance of an F2 Expression common to some instances of F3 Manifestation Product Type or F4 Manifestation Singleton would be identified with the one manifestation of a particular expression that has been selected to be “representative” for this expression. This model does not correspond to any explicit library information. Rather, it describes an implicit process behind the appellation creation process: The very fact of composing an identifier for an instance of F2 Expression using the identifier of one particular manifestation makes the latter “representative” for the corresponding expression. Note that the “representative” manifestation is not necessarily the historically first or earliest one. It might be the most popular one, or the first one detected. It might be a fragment of a whole detected later. As this introduces a kind of arbitrariness, the authors found this model interesting when discussing the respective practices. Similarly, an instance of F1 Work can only be identified if a corresponding instance of F2 Expression is selected as “representative”.

Figure

2.1.7. Photographs and animated images

Works realised using the photographic medium are particular, in that their essence mostly resides in the capturing of features of portions of the physical world, using automatic devices (either analogue or digital). That notion may seem close to the notions modelled in FRBR_OO as F21 Recording Work, F26 Recording, and F29 Recording Event. However, it is not necessary to consider all kinds of photographs as instances of F21 Recording Work; it depends on their intended functionality. Photographs that were made for the explicit purpose of documenting something are clearly instances of F21 Recording Work, while art photographs can be regarded simply as instances of F1 Work. Besides, double instantiation always makes it possible to deal with any expression of a photographic work as an instance of both F2 Expression and E38 Image, which allows one to use the CIDOC CRM property P138 represents (has representation) in order to record the relationship between a photograph and the sitter who can be recognized on the photograph. Additionally, that relationship is accounted for through the following statement: F28 Expression Creation (P2 has type: E55 Type {making a photograph}) P14 carried out by: E39 Actor (P14.1 in the role of:E55 Type {sitter}).

In the same way, not all motion pictures are instances of F21 Recording Work. Animated cartoons and computer-generated films cannot be said to “record” anything. Even though fiction movies can be said to record actors’ performances, and even though animated cartoons and computer-generated films, when they include a soundtrack, can be analysed as having a component that is an instance of F26 Recording, these should all be instantiated as F1 Work, rather than F21 Recording Work. The explicit intention to capture features of a given perdurant in order to document that perdurant is what should determine whether an animated image is to be regarded as an instance of F21 Recording Work.