Frequently Asked Questions
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Is the published set of RDA vocabularies complete and stable?
Yes and no. Further development of the RDA vocabularies is incorporated in the tasks of the RSC Technical Working Group as well as the RDA Development Team. The RSC expects to add, update, and deprecate elements and concepts as the need arises. Version control is applied to versions and releases of the RDA Vocabularies in GitHub and the RDA Registry. The RDA vocabularies are stable in that the canonical IRIs will not be changed, and usual good practice will be used when amending or removing classes and properties. For example, if a property is deleted from RDA itelf, it will be deprecated in the RDA Registry but not deleted, according to the deprecation policy. See the section on "Deprecation" in About the RDA Registry and vocabularies for further information.
Why are the IRIs unreadable?
After a great deal of discussion, the JSC (predecessor of the RDA Steering Committee) decided to use opaque IRIs for the element sets. This follows the practice established for the value vocabularies, and reflects the international environment of RDA and its translations. The RSC is also aware of the problems associated with using transparent, human-readable IRIs as a mnemonic device, especially when the properties and values of bibliographic display labels may be further developed. However, English-readable IRIs have been declared owl:sameAs to their canonical, opaque counterparts to alleviate any inconvenience this might cause for English-based linked data applications. The same facility may be developed for other languages, based on translations of RDA, in the future. The mnemonic accuracy of these IRIs is not guaranteed.
Why do some of the published elements have weird labels and definitions?
This is the result of applying a mechanical device to verbalize RDA labels and definitions to clarify their semantics, specifically the direction of a relationship property, and to create labels and definitions for versions of the properties unconstrained by the RDA domain model based on IFLA Library Reference Model (LRM).
Why are the translations of the RDA element sets and value vocabularies incomplete and out of date?
Translations are based on RDA Reference data that reflect the content of RDA as it is developed by the RDA Steering Committee. There is an inevitable time-lag before changes are applied to RDA Reference and the Registry vocabularies. Procedures for minimizing the delay are being developed.
What is RDA Reference?
RDA Reference comprises the RDA element sets and value vocabularies and their translations, and associated maps and alignments. See the section on "RDA Reference" in About the RDA Registry and vocabularies for further information.
RDA Reference comprises the RDA element sets and value vocabularies and their translations, and associated maps and alignments.
What are recording methods?
A value of an RDA element may be recorded as a string using three methods:
- An unstructured description. An example is a free text note or a name of an agent.
- A structured description is a string that aggregates string values from other elements using a string encoding scheme. An example is an access point for agent that may include a string for a name of person and a string for a date of birth.
- An identifier. An example is an ISBN or local identifier.
In this context, a "string" is a sequence of alphanumeric symbols and punctuation marks intended primarily for human consumption.
The RDA guidance and instructions were developed during the RDA Toolkit Restructure and Redesign (3R) Project to further generalize these methods of identifying a related entity, and to accommodate an explicit fourth method for linked data applications:
- An IRI for the entity as a real-world object; that is, a "thing".
Where do I direct questions I have about the RDA Vocabularies that aren’t answered here?
Please email questions about the content of the RDA Vocabularies to the Chair of the RDA Steering Committee (firstname.lastname@example.org). Questions about technical issues can be emailed to the RDA Technical Team Liaison Officer.
Where can I find more information about the processes used to develop and maintain the published RDA vocabularies?
See the section on "Data flow" in About the RDA Registry and vocabularies for information about the processes used to maintain the RDA vocabularies.