Wikidata:Property proposal/expression of

expression of

Originally proposed at Wikidata:Property proposal/Creative work

   Done: expression of (P6524) (Talk and documentation)

Description	expression realized by a work in the FRBR model
Data type	Item
Example 1	half cent (Q1283200) -> penny (Q161604)
Example 2	Macbeth (Q929582) -> Macbeth (Q130283)
Example 3	Georgius, Monachus. Commentarium in librum Peri staseōn. (French) (Q61719087) -> Georgius, Monachus. Commentarium in librum Peri staseōn. (Work) (Q61719103)
Example 4	Homérova Ilias (Q17566229) -> Iliad (Q8275)
Example 5	Iliad (Q17559055) -> Iliad (Q8275)
Source	https://en.wikipedia.org/wiki/Functional_Requirements_for_Bibliographic_Records#Relationships
Planned use	Needed to describe GLAM/cultural heritage resources following the standard conceptual models and implementations (FRBR/FRBRoo/LRM/BIBFRAME/RDA)

Motivation

I'm trying to use wikidata to describe cultural heritage resources, particularly coins, following the Work--> "expressed in" Expression --> "manifested in" Manifestation -->"instantiated in" Item conceptual model. I find that "instance of" doesn't appropriately describe the transition from Work to Expression, and am proposing "expression of" (akin to the already-existing manifestation of (P1557)).  – The preceding unsigned comment was added by Heberlei (talk • contribs) at 18:58, January 30, 2019‎ (UTC).

Discussion

• @Heberlei: See other property proposals - your examples should show how you would use this property: a specific resource is an expression of a specific work. The items listed in your examples seem to be just generic items associated with describing creative works in general. ArthurPSmith (talk) 16:41, 31 January 2019 (UTC)

@ArthurPSmith: For example, and piggybacking a little here on the examples from the "manifestation of" proposal (https://www.wikidata.org/wiki/Wikidata:Property_proposal/Archive/25#P1557), the Work Iliad (Q8275) has among its expressions the Catalan translation Iliad (Q17559055) and the Czech translation Homérova Ilias (Q17566229).

The Catalan expression is manifested, among others, in the special print run of thirty, Iliad (Q17559097). An instance of this manifestation is OCLC # 1044429175, a single item held by a single library (HGC).

The Czech Expression Homérova Ilias (Q17566229) is manifested in OCLC 841632469, the 1911 edition of the Skoda translation, published by the Czech Academy of Emperor Franz Joseph for Science, Literature and Art as part of the Classical Library ("Bibliotéka klassiku") series. A copy (of my invention) of this edition called Copy Franz Joseph 1, held by Library XYZ, custom-bound and with marginalia by Emperor Franz Joseph, is an instance of this edition.

So some statements we could make about these items are:

Homérova Ilias (Q17566229) <expression of> Iliad (Q8275)

Iliad (Q17559097) manifestation of (P1557) Iliad (Q17559055)

HGC-held item described at OCLC # 1044429175 (item) instance of (P31) Iliad (Q17559097)

Iliad (Q17559055) <expression of> Iliad (Q8275)

OCLC # 841632469 (edition) manifestation of (P1557) Homérova Ilias (Q17566229)

"Copy Franz Joseph 1" instance of (P31) OCLC 841632469

The concept of an Expression pertains to the modeling of cultural heritage resources. The FRBR model (https://en.wikipedia.org/wiki/Functional_Requirements_for_Bibliographic_Records) describes a cultural heritage resource as a Work (an abstract entity) realized in an Expression (the specific yet immaterial form and set of signs), manifested in a set of physical carriers that all bear the same characteristics, and instantiated in a single object from that set. To map to wikidata / allow cultural resources to be described in wikidata following this model, the "expression of" property is indispensable:

Object: instance of (P31): Manifestation: manifestation of (P1557): Expression: <expression of>: Work.

A further example, taken from Numismatics, is United States dollar (Q4917), conceptually a complex work consisting of units that are themselves individual conceptual works, among them United States dollar (currency unit) (Q61692784) and penny (Q161604). They are expressed in denominations, that is abstract entities representing an authorizing body's decisions about the multiples/fractions/groupings of a currency's unit to realize at any given time; examples of expressions of a currency unit are eagle (Q832721) (expression of United States dollar (currency unit) (Q61692784)) and half cent (Q1283200) (expression of penny (Q161604)). Expressions are manifested in issues, i.e. all realizations of the half-cent denomination that at the point of production share the same physical characteristics (i.e. its properties pertain to all exemplars of the issue, e.g. format (coin/banknote); measurements; design etc.). An example of a manifestation of half cent (Q1283200) is the 1793 Half Cent issue with Lady Liberty facing left, classed by Numismatists as "Cohen 2" or "Breen 2" (no wikidata item; described e.g. at https://www.pcgs.com/coinfacts/category/half-cents/liberty-cap-half-cent/type-1-facing-left-1793/650). An instance of this manifestation would be a single exemplar of this issue (its properties pertain to the single object).

So some statements we could make about these items are:

penny (Q161604) (i.e., the unit "cent") subclass of (P279) United States dollar (Q4917) (i.e., the currency)

half cent (Q1283200) (i.e., the denomination "1/2 of the unit 'cent'") expression of penny (Q161604) (i.e., the unit "cent")

Cohen 2 (i.e. the issue) manifestation of (P1557) half cent (Q1283200) (i.e., the denomination "1/2 of the unit 'cent'")

Conceptual Background:

The International Federation of Library Associations and Institutions provides the following definition for the concept of an Expression:

“A distinct combination of signs conveying intellectual or artistic content. An expression is the specific intellectual or artistic form that a work takes each time it is “realized.” Expression encompasses, for example, the specific words, sentences, paragraphs, etc. that result from the realization of a work in the form of a text, or the particular sounds, phrasing, etc. resulting from the realization of a musical work. The boundaries of the entity expression are defined, however, so as to exclude incidental aspects of physical form, such as typeface and page layout for a text, unless, due to the nature of the work, these are integral to the intellectual or artistic realization of the work as such.” (IFLA Library Reference Model: A Conceptual Model for Bibliographic Information (p. 23). https://www.ifla.org/files/assets/cataloguing/frbr-lrm/ifla-lrm-august-2017.pdf)

The object-oriented definition of the concept of an Expression expands as follows:

This class comprises the intellectual or artistic realisations of works in the form of identifiable immaterial objects, such as texts, poems, jokes, musical or choreographic notations, movement pattern, sound pattern, images, multimedia objects, or any combination of such forms that have objectively recognisable structures. The substance of F2 Expression is signs.

Expressions cannot exist without a physical carrier, but do not depend on a specific physical carrier and can exist on one or more carriers simultaneously. Carriers may include human memory.

Inasmuch as the form of F2 Expression is an inherent characteristic of the F2 Expression, any change in form (e.g., from alpha-numeric notation to spoken word, a poem created in capitals and rendered in lower case) is a new F2 Expression. Similarly, changes in the intellectual conventions or instruments that are employed to express a work (e.g., translation from one language to another) result in the creation of a new F2 Expression. Thus, if a text is revised or modified, the resulting F2 Expression is considered to be a new F2 Expression. Minor changes, such as corrections of spelling and punctuation, etc., are normally considered variations within the same F2 Expression. On a practical level, the degree to which distinctions are made between variant expressions of a work will depend to some extent on the nature of the F1 Work itself, and on the anticipated needs of users. (https://www.ifla.org/files/assets/cataloguing/FRBRoo/frbroo_v_2.4.pdf)

Heberlei (talk) 14:55, 11 February 2019 (UTC)

@Heberlei: I'm not entirely sure I follow, but I think it would be helpful (to me but also others) to translate your above text into specific examples and add them in the proposal template under "example 1", etc. For example half cent (Q1283200) -> penny (Q161604) presumably? ArthurPSmith (talk) 18:08, 12 February 2019 (UTC)

@ArthurPSmith: [Inserting after edit conflict:] I've added the above examples to the template, as well as two additional ones, which will hopefully help to make things clearer:

Macbeth (Q929582) "expression of" (film adaptation) Macbeth (Q130283)

Georgius, Monachus. Commentarium in librum Peri staseōn. (French) (Q61719087) "expression of" (French translation) Georgius, Monachus. Commentarium in librum Peri staseōn. (Work) (Q61719103) Heberlei (talk) 18:58, 13 February 2019 (UTC)

•  Support Ok, thanks for getting this into a suitable format! I'm going to notify the "books" project as I think they have been the ones most involved with FRBR issues. ArthurPSmith (talk) 18:37, 13 February 2019 (UTC)

WikiProject Books has more than 50 participants and couldn't be pinged. Please post on the WikiProject's talk page instead.

•  Support Necessary property for Functional Requirements for Bibliographic Records (Q16388) modeling. Useful to distinguish between Wikidata items that are the abstract concept of the thing (i.e. work) and specific realizations of that thing (i.e. expression). Louize5 (talk) 19:59, 13 February 2019 (UTC)
•  Question How does this relate to edition or translation of (P629)? I think that would be used for most of the book examples above. ArthurPSmith (talk) 15:11, 15 February 2019 (UTC)

• @ArthurPSmith: edition or translation of (P629) actually conflates two distinct FRBR concepts: expression and manifestation. An edition would be an example of a type of manifestation, hence would fall under the existing property manifestation of (P1557). A translation is an example of an expression, hence would fall under the proposed property "expression of". So conceptually, edition or translation of (P629) is not viable for describing resources within a FRBR-based data model. Both edition or translation of (P629) and the proposed "expression of" also apply to any resource regardless of format, whereas edition or translation of (P629) is limited to specific resources (e.g. books, but not coins or performances). E.g.:

half cent (Q1283200) "expression of" penny (Q161604)

"Cohen 2" (https://www.pcgs.com/coinfacts/coin/1793-1-2c-cohen-2-bn/35006: issue, the numismatic equivalent to a bibliographic edition) manifestation of (P1557) half cent (Q1283200)

Heberlei (talk) 19:43, 19 February 2019 (UTC)

So, would edition or translation of (P629) be deprecated and replaced? --Yair rand (talk) 21:33, 19 February 2019 (UTC)

• @Yair rand: edition or translation of (P629) is conceptually different from "expression of" and manifestation of (P1557). It serves a more casual descriptive purpose, but is unsuitable for rigorous conceptual modeling based on FRBR because it conflates two distinct descriptive levels and is too format-specific. As such, I would think "expression of" and edition or translation of (P629) can co-exist, as in fact edition or translation of (P629) and manifestation of (P1557) have already done. Heberlei (talk) 01:27, 22 February 2019 (UTC)

@ArthurPSmith, Louize5, Heberlei, Yair rand:  Done: expression of (P6524). − Pintoch (talk) 21:31, 21 February 2019 (UTC)