Help:Reference and provenance data

Semantic MediaWiki statement with untested claim or fact
Semantic MediaWiki statement containing a factual claim
Example implementation

Statements recorded with Semantic MediaWiki mostly contain untested claims which in general is interpret as an "incomplete claim for which evidence is yet unavailable"1.

In some instances it is helpful to record provenance2 metadata as reference to improve an understanding and context of a claim.

For example, the statement "Berlin has a population of 3 500 000" is untested in context of a missing reference or axiomatic declaration, yet in spite of lacking evidence the claim is expected to be "true"3 under the open-world assumption.

Some users (see SMW issue 985).4 and in some situations, relying on untested claims maybe challenging therefore Semantic MediaWiki 2.5.0Released on 14 March 2017 and compatible with MW 1.23.0 - 1.29.x. introduced the new datatype "Reference"Holds a value that associates it to individual defined provenance metadata record5 with which an untested claim can be transformed into a factual claim by recording provenance metadata678 (as to when, how, by whom a claim was made) and hereby allows to state tangible or convergent evidence1.

For an exhaustive description on how to use the data type for provenance recording, please see the (see SMW issue 1808).6 as well as the Semantic MediaWiki Sandbox example page on the corresponding pull request #1812.9

Semantic Cite extension vs. Reference datatype[edit]

In extension "Semantic Cite"Allows to manage citation resources using semantic annotations where a statement is known as citation resource, a reference represents a "loose" attachment to any text or link without correlation to a specific claim or annotation. On the other hand a typed reference (and hereby its provenance data) is individually linked to its statement and inherently bound to a specific value assignment and only exists in context of that statement and ceases to exist when the statement is removed.

See also[edit]


  1. a b  Fact, Opinion, False Claim, or Untested Claim? describes as "Untested claim: Vague, ambiguous, or incomplete claim OR factual claim for which evidence is yet unavailable."
  2. ^  Provenance is understood as "... information about entities, activities, and people involved in producing a piece of data or thing, which can be used to form assessments about its quality, reliability or trustworthiness ..." according to
  3. ^  As a logical axiom "everything can be true unless proven otherwise", see The Open World Assumption
  4. ^  Semantic MediaWiki: GitHub issue gh:smw:985
  5. ^  Semantic MediaWiki: GitHub pull request gh:smw:1812
  6. a b  Semantic MediaWiki: GitHub issue gh:smw:1808
  7. ^  Sudha Ram, Jun Liu. "A New Perspective on Semantics of Data Provenance". (2009): 35--40.
  8. ^  Yogesh L Simmhan, Beth Plale, Dennis Gannon. "A Survey of Data Provenance in e-Science". ACM 34.3 (2005): 31--36. doi: 10.1145/1084805.1084812
  9. ^  Semantic MediaWiki: Sandbox example sb:smw:1812