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Documentation and status of DCMI terms

Title: Documentation and status of DCMI terms
Creator: DCMI Usage Board
Date modified: 2002-07-13
Description: This document summarizes a number of
                  Decisions made by the Usage Board with
                  regard to the authoritative documentation
                  of DCMI metadata terms and to their
                  status. This document is pointed to from
                  the official list of Usage Board Decisions [1].

  1. Documentation of DCMI metadata terms

1.1. DCMI metadata terms, hitherto announced and documented in "DCMI Recommendations" under the jurisdiction of the DCMI Advisory Board (e.g., see [2] and [3]) will henceforth be authoritatively documented in a set of Web pages under the jurisdiction of the Usage Board. This shift of documentary responsibility follows the transfer of decision-making authority from the Advisory to the Usage Board.

1.2. These documents, accessible from, currently include:

  -- DCMI Usage Board Decisions [4]: each of which is 
     numbered for unambiguous identification;

  -- DCMI Elements and Qualifiers [5]: a complete
     listing of all elements, element refinements, and
     encoding schemes, including all superseded versions
     of term declarations for individual terms;

  -- Elements and Element Refinements - a Current List [6]:
     a complete listing, generated automatically from
     [5], of all elements and element refinements
     with their most up-to-date term declarations;

  -- Encoding Schemes - a Current List [7]: a complete
     listing, generated automatically from [5], of all
     encoding schemes in their most up-to-date versions;

  -- The DCMI Type Vocabulary [8];

  -- References from DCMI Term Definitions [9]: an updated
     list of references cited in term definitions.

1.3. DCMI metadata term declarations use the following descriptive attributes:

   VMS-ID: A unique identifier for a time-stamped version of a
                  term declaration. This identifier is
                  used exclusively within the context of a
                  Vocabulary Management System (VMS) for documenting
                  and tracking editorial or status changes in
                  the declarations of metadata terms. In accordance
                  with the DCMI namespace policy [14], a version 
                  change in the VMS does not imply changes in the 
                  semantic essence of a metadata term, and consequently
                  it does not correspond to a change in a term's namespace
                  URI, which by policy will remain a permanent and stable
                  identifier within the DCMI namespaces.

   Name: The unique token assigned to the term.

   URI: The unique identifier for a term, formed from a term's
                  name and a DCMI namespace URI according to an algorithm
                  described in the DCMI namespace policy [14].

   isDefinedBy: The namespace to which a term belongs, as explained in
                  the DCMI namespace policy.

   Label: The human-readable label assigned to the term.

   Definition: A statement that represents the concept and essential 
                  nature of the term.

   Comment: Additional information about the term or its application.

   References: A resolvable link to a reference cited in a term definition 
                  or comment. The references are maintained in a separate
                  document [9].

   Term Type: The type of term according to DCMI grammatical principles, 
                  currently one of the following:

              <a href="/usage/documents/principles/#element"></a>
              <a href="/usage/documents/principles/#element-refinement"></a>
              <a href="/usage/documents/principles/#encoding-scheme"></a>
              <a href="/usage/documents/principles/#controlled-vocabulary-term"></a>

   Terms Qlfd: For an Encoding Scheme, the URI of an Element qualified.

   subPropertyOf: For an Element Refinement, the URI of the Element qualified.

   Decision: A pointer to a decision of the DCMI Usage Board associated
                  with a specific version of a term declaration.

   Term modified: The date of a specific version of a term declaration.

   Term issued: The date a term was first declared.

   Replaces: A pointer to earlier versions of a term declaration.

   isReplacedBy: A pointer to later versions of a term declaration.

   Status: The status of the term assigned by the Usage Board, 
                  currently one of the following:
                  <a href="/usage/documents/process/#recommended"></a>
                  <a href="/usage/documents/process/#conforming"></a>
                  <a href="/usage/documents/process/#registered"></a>
                  The types of status that can be conferred will differ
                  between types of term in ways described below and in the 
                  DCMI Usage Board Process [10].

1.4. DCMI metadata terms are versioned individually. Any change in a term declaration, such as in the wording of a definition or in the status assigned to a term by the Usage Board, triggers the creation of an updated term declaration. Updated versions of term declarations point back to superseded versions such that it will always be possible to reconstruct the state of all term declarations (e.g., the wording or spelling of definitions and comments, referenced citations, or assigned status) as of any particular point in time. Each successive version of a term declaration points to a corresponding decision event listed at These decision events, in turn, point to formal Usage Board documents, meeting notes or agendas, working-group proposals, or any other materials relevant as context for the addition or revision of a term declaration. For citation purposes, each such decision event has a citable decision number and URI.

1.5. The Web pages maintained by the Usage Board are intended to serve as the canonical (authoritative) source of all other metadata-term representations maintained by DCMI, such as ready-reference Web pages or machine-processable schemas, whether those derived representations are created by automatic extraction (as in the case of and or by manually copying from the canonical representation.

  1. Editorial changes to specific term declarations

2.1. The URL associated with the citation referenced as "TGN" was changed from to This change is recorded in a comment in

2.2. The URL associated with the citation referenced as "ISO3166" was changed from to This change is noted in a comment in

2.3. A spelling inconsistency between the definitions of dct:replaces and dct:isReplacedBy was corrected by changing the spelling of "superseded" (from "superceded") in the definition of

2.4. The wording of the Comment (and related reference) of was changed to point to the DCMI Type Vocabulary instead of the superseded Dublin Core Types working draft. In the same Comment, an all-uppercase reference to "FORMAT" was changed to "Format").

2.5. A namespace URI was assigned to each current term declaration in accordance with the DCMI Namespace Policy,

2.6. On the occasion of its change in status from "Domain- Specific" to "Recommended", the Usage Board re-worded the definition of to make it more generic. See

  1. Assignment of status to DCMI terms

3.1. According to the principles in force as of May 2002, DCMI metadata terms were to be assigned a status of Registered or Recommended, and Recommended terms could have a further status of Cross-Domain, Domain-Specific, or Obsolete (see Section 3 of Assignment of status on this basis to legacy metadata terms had not, however, been yet completed. Finding the distinctions between these types of status to be problematic, the Usage Board undertook a revision and clarification of the status categories at its meeting in Bath on 12-13 May 2001. The results of this revision, along with the explicit assignment of status on this new basis, are described below.

3.2. The status Recommended will henceforth be reserved for metadata terms of demonstrated usefulness for "resource discovery across domains".

3.3. On the occasion of this clarification of status generally, the Usage Board is explicitly assigning the status of Recommended to all elements and element refinements approved in [2], [3], and [11].

3.4. The status of Conforming will be given to any terms that "conform to DCMI grammatical principles" -- for example, element refinements must fall within the semantic scope of the elements being refined -- without strict limitation with regard to "usefulness for resource discovery" and "cross-domain applicability". To be accepted, proposed terms must not overlap semantically with existing terms.

3.5. In their proposals, working groups must demonstrate and document that any proposed new terms have the substantial support of working-group members. Evidence of such support can include votes held on mailing lists or in face-to-face meetings or positive endorsements from members of the dc-general mailing list. Working groups should also indicate the level of status sought for each term.

3.6. The Usage Board reserves the right to modify the wording of proposals on acceptance, especially for the purpose of making definitions more generic with respect to domain of application.

3.7. The statuses of Cross-Domain and Domain-Specific will be dropped, and the status of Domain-Specific will be removed from three terms to which it had been assigned (dct:audience, dct:conformsTo, and dct:mediator).

3.8. In accordance with the policy outlined above, status is hereby assigned to legacy metadata terms as follows:

  -- To all legacy Elements and Element Refinements the
     status of Recommended. To several such terms to
     which previously the status of Domain-Specific
     had been assigned [11], the Usage Board has
     broadened their wording to make them more generic
     in application.

  -- To all legacy Encoding Schemes the status of
     Registered. This also applies to three legacy
     Encoding Schemes -- DCMI Period, DCMI Point, and
     DCMI Box -- that are currently specified in
     documents of the type "DCMI Recommendation".
     As a general rule, the Usage Board will
     henceforth assign the status of Registered to
     all new encoding schemes.

  -- To all controlled vocabulary terms of the DCMI
     Type Vocabulary the status of Recommended.

3.9. As with Recommended terms, Conforming terms accepted into a DCMI namespace come under the jurisdiction of the Usage Board, which will retain the responsibility for maintaining those terms over time. Proposals for changes in the wording or status of Conforming terms must go through the normal processes for Usage Board proposals.

3.10. The document "DCMI Usage Board Review of Application Profiles" [12] defines the term "Application Profile" in the DCMI context and outlines the criteria by which the DCMI Usage Board can review an Application Profile and assign to it a status. This document describes how DCMI terms can be used in conjunction with terms from namespaces not maintained by DCMI.

3.11. The historical documentation for the vote on the first set of qualifiers by the (then) Usage Committee in the Spring of 2000 has been re-organized under [13].

[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]