Archive for August, 2012

Dublin Core archaeology

DCMI logoTriggered by a question from Stefane Fermigier, I did some digging in the archives of the Dublin Core Metadata Initiative (DCMI).

The question was why the Dublin Core terms for different dates use different naming pattern. For example, the date when a document was created is expressed simply with created, but the dates when one was submitted for review or accepted use an apparent variant of the hungarian notation, i.e. dateSubmitted or dateAccepted.

It turns out that the original set of Dublin Core metadata elements from 1998 only contained a single generic date element that was vaguely defined as follows:

  • date – A date associated with the creation or availability of the resource.

Then a few years later in 2000 the standard group introduced the concept of “qualifiers” for “refining” the definition of a more generic element. The following date qualifiers were specified:

  • created – Date of creation of the resource.
  • valid – Date (often a range) of validity of a resource.
  • available – Date (often a range) that the resource will become or did become available.
  • issued – Date of formal issuance (e.g., publication) of the resource.
  • modified – Date on which the resource was changed.

Another two years down the line, in 2002, the standards group adopts a nice change and status tracking mechanism and declares to “all legacy Elements and Element Refinements the status of Recommended”. That makes tracking any further changes pretty easy.

For example, later that year two new date refinements were proposed as submitted and accepted. However, when accepting those proposals, the standards group adjusted the terms to dateSubmitted and dateAccepted to produce the following two definitions:

In the end the question of why exactly a different naming pattern was used remains unclear, but the record shows that the decision to change the names was explicitly made by the standards group ten years ago. Someone closer to the DCMI group might still remember the details of that decision.