Page:ARL White Paper on Wikidata Opportunities and Recommendations.pdf/21

 is further described using qualifiers to include when the prize was awarded and the name of the winner:

The Able McLaughlins (item) → award received (property) → Pulitzer Prize for Fiction (value) → point in time (qualifier) → 1924 (value) → winner (qualifier) → Margaret Wilson (value)

The claim made in each individual property-value statement can be supported with references. An item can also have sitelinks, which are interwiki links (links to other Wikimedia projects). Items and their statements can be created and edited by anyone.44

Properties, on the other hand, are more controlled since they require a community review process. Properties are the equivalent to metadata elements/fields since they are used to record values. Properties in Wikidata are equivalent to predicates in general linked data terminology. A property describes a relationship between the item and another item, an identifier, or a literal value (free text string, date, etc.). As of February 2019, there are over 6,000 properties, both general and domain-specific, that are instance supported on Wikidata.45

Properties that relate to existing or well-used metadata standards will be supported by the community—so getting support for new properties needed by libraries should be straightforward. However, at the time of writing, properties equivalent to common standards used in both libraries and other communities are inconsistent—often the first step for

ARL White Paper on Wikidata: Opportunities and Recommendations