Help:Property constraints portal/No bounds

no-bounds constraint (Q51723761) specifies that the value of the property should not be used with upper and lower bounds, i.e. with values such as “100” instead of “100±1” or “100±0”. This constraint type should only be used on properties with quantity datatype.

According to the datamodel described at mw:Wikibase/DataModel#Quantities, bounds of quantity datatype properties represent uncertainty (Q13649246), of which measurement uncertainty (Q1403517) of physical quantities only are relevant. Non-physical quantities typically do not have this concept of bounds which indicate uncertainty, thus the Wikidata property should not use it.

Examples:

• values of maximum capacity (P1083) are generally not the result of a measurement process, values are typically set in a regulatory process by some authority. If the number is an estimate of a physical quantity, bounds can be used, e.g. for Colosseum (Q10285) at Q10285#P1083.
• values of number of children (P1971) are not the result of a measurement process; in case of contradicting information about the value in different sources, multiple claims with values according to the sources should be used, rather than bounds. If the uncertaintity of the number of children is quantified, bounds can be used, e.g. a person that had 100+/-10 children.

If no constraint scope (P4680) is specified, this constraint is checked everywhere.

Possible actions

There are several possible ways to address a violation of this constraint:

• it is possible that bounds cover the range of possible values under different conditions; values for maximum capacity (P1083) of a stadium may depend on regulatory factors of the event for which it is used; use qualifiers on different claims to distinguish these values
• it is possible that bounds cover the range of different known values of a countable quantity such as number of children (P1971); use separate claims for each value that can be referenced
• if the number implies some unquantified uncertainty, add the qualifier sourcing circumstances (P1480) with value circa (Q5727902).

Parameters

This constraint does not have any qualifier parameters.

Maintenance

• Overview of properties with quantity datatype and a no-bounds constraint (Q51723761): SPARQL; see also: Category:Properties with no bounds constraints
• Overview of properties with datatype other than quantity and a no-bounds constraint (Q51723761): SPARQL (this query result should be empty)
• Violations of this constraint:
  • full list (mainsnak)
  • number of violations by property (mainsnak)
  • number of violations by property (qualifier)
  • number of violations by property (reference)