P82a/b are the preferred properties for a date range

[VincentDucatteeuw]

CIDOC-CRM has two properties for defining time-spans with both having two subproperties

• P81 ongoing throughout
• • P81a end of the begin
• • P81b begin of the end
• P82 at some time within
• • P82a begin of the begin
• • P82b end of the end

P82 at some time within is a necessary property to use in the gazetteer, while P82 is an optional property in the gazetteer.

Examples of other projects using similar data ranges:

• https://www.goudatijdmachine.nl/2021/11/24/onder-de-motorkap-van-de-gouda-tijdmachine-omeka-s/#page-content
• https://mapping-manuscript-migrations.github.io/sparql/sparql_tutorial.html
• https://adamlink.nl/geo/streets/list

[VincentDucatteeuw]

These properties are defined as closed intervals CMR documentation, p.4-5: https://cidoc-crm.org/sites/default/files/issue%20443%20-%20Implementing%20CIDOC%20CRM%20in%20RDF%20v1.1.pdf

[VincentDucatteeuw]

For the example dataset 1 year duration was chosen for the P82a/b properties and a 1 day duration was chosen for the P81a/b properties. Further look into how to determine formal date ranges for historical documents.

[VincentDucatteeuw]

For the Wegwijzer test data '1898_UB_PARSED" the publication year was chosen to determine the values of the P82a/b properties. i.e. the described temporal phenomenon is a place observation mentioned in the Wegwijzer that is definitely ongoing “at some time within” the interval "1898-01-01T00:00:00" - "1898-12-31T23:59:59.").