Previous projects have developed CIDOC-CRM mappings of museum data, including the British Museum, SAAM, and YCBA. To complete these mappings, many of the institutions have defined custom concepts, classes, and properties that extend the CIDOC-CRM. Should the AAC use any of these extensions? If so, which ones?
Additionally, the CRM has published a series of extensions, including the CRMpc and CRMinf. Are any of these useful?
Our current practice is to use the CRM when possible, and to choose from extensions as needed to fill gaps. In particular, we are using the CRMpc extension to allow for CRM N.1 properties and the http://www.qudt.org ontology for computable dimensions.
In general, we prefer existing, widely used extensions over creating new ones.
We should look to broadly adopted ontologies first, and then any community extensions. So if we need a term from BM/YCBA, we should use it.
Don't look at http://crm.rkbexplorer.com/. It "polluted CRM" by adding 2x more custom properties such as PX.watch_pendant_made_in. Instead, the next mapping we did, added a few custom properties, and uses a lot more of CIDOC CRM and generic mechanisms for extension.
Search for "revealed" at http://vladimiralexiev.github.io/pubs/.
E.g. the above would be modeled like this (rdf:type skipped for brevity):
<object/123> p2_has_type <watch>; P42_is_composed_of <object/123/pendant>. <object/123/pendant> p2_has_type <pendant>; P108i_was_produced_by <object/123/pendant/production>. <object/123/pendant/production> P7_took_place_at <place>.
(From conference call, 9/28/2016)
How frequent or infrequent will this issue be?
RS: Concern that we conform to the CRM but not to what the rest of the world does for common data entities (like names)
(From Vladimir 12/13/2016)
For Getty CONA mapping I've defined some simple extensions like crmx:preferred, crmx:sort_order, crmx:property (the missing piece of crm:E13_Attribute_Assignment). See CRMX at Getty (Rob has access). There are a few more to cover CCO, eg crmx:P2_extent "art of object or work contributed by an agent, measured in a dimension, or described by a subject"