- From: Vladimir Alexiev <vladimir.alexiev@ontotext.com>
- Date: Wed, 1 Apr 2020 11:46:26 +0300
- To: public-esw-thes@w3.org, Rob Sanderson <rsanderson@getty.edu>
- Message-ID: <CAMv+wg7gNZKOLQsKKw5S1wTPpbEz9VLPCgV1gQ3dWPKTzTdsnA@mail.gmail.com>
Hi! Skos is provided in one of two formats (profiles): - Simple (SKOS) - Structured (SKOSXL <https://www.w3.org/TR/skos-reference/#xl>+Advanced Documentation Features <https://www.w3.org/TR/skos-primer/#secadvanceddocumentation> with metadata/provenance props). "Documentation" means notes, definitions, etc It's a common practice to publish "structured" with redundancy, to cater to both "simple" consumers and "structured" consumers: - SKOSXL recommends structured labels to be published redundantly: as plain SKOS labels and as skosxl:Label. Dumbing-Down to SKOS Lexical Labels <https://www.w3.org/TR/skos-reference/#L780> defines how to provide structured and plain labels together. - Not sure about notes, as neither SKOS nor SKOSXL defines a class Note (Getty defines gvp:Note), nor separate properties. So skos:definition and friends would carry both a string and a resource, which will complicate consumption. Currently a SKOS dataset or API does not have a way to declare its profile. https://github.com/NatLibFi/Skosmos/issues/477 describes some troubles related to this: - Skosmos uses "duplicate label matching logic" to display the label below just once, and assumes label redundancy. <concept> skos:prefLabel "foo"@en; skosxl:prefLabel [skosxl:literalForm "foo"@en] - However, there is no similar logic for notes, so it would display labels in duplicate. To avoid complicated duplicate matching logic at the consumer, I think we should define two SKOS profiles: simple vs structured. - Should "structured" subsume "simple", i.e. redundantly provide the same strings as simple labels/notes? That will simplify life for data providers - Do we need the two aspects separately: structured labels vs structured notes? - The profile should be communicated: - In HTTP request: client should be able to request "simple" or "structured" - In HTTP response - In the description of ConceptScheme and VOID/DCAT Dataset (property dct:conformsTo) - ConceptSchemes should provide completeness guarantees: if one label or note is structured, then all labels respectively notes are available as structured. I think these SPARQL tests should be used: - Some SKOSXL label exists: <scheme> ^skos:inScheme/(skosxl:prefLabel|skosxl:altLabel|skosxl:hiddenLabel) ?label - Some skos:definition or skos:scopeNote is non-literal. I exclude: skos:changeNote, skos:historyNote, skos:editorialNote because these may be structured without the "business payload" notes being structured; skos:example because conceivably it can point to a resource; skos:note because that's a super-prop of excluded props (but many people use it directly, so I'm not sure): <scheme> ^skos:inScheme/(skos:definition|skos:scopeNote) ?definition Assuming subsumption/redundancy (that "structured" includes "simple") and that the client can use SPARQL then "duplicate matching" can be done easily in SPARQL. Eg something like this: select ?lab ?prop ?propLabel ?metadata { <concept> skos:prefLabel ?lab. optional { <concept> skosxl:prefLabel ?label. ?label skosxl:literalForm ?label; ?prop ?metadata filter (?prop != skosxl:literalForm) optional {?prop (rdfs:label|skos:prefLabel) ?propLabel} # need lang preferencing here! } } select ?def ?prop ?propLabel ?metadata { <concept> skos:definition ?def. optional { <concept> skos:definition ?definition. ?definition rdf:value ?def; ?prop ?metadata filter (?prop != rdf:value) optional {?prop (rdfs:label|skos:prefLabel) ?propLabel} # need lang preferencing here! } } Are there any takers to formalize SKOS profiles? -- Vladimir Alexiev, PhD, PMP Chief Data Architect Sirma AI, trading as Ontotext: https://www.ontotext.com, LinkedIn <https://www.linkedin.com/company-beta/208070>, Twitter <https://twitter.com/ontotext>, Rate GraphDB <http://www.capterra.com/database-management-software/reviews/157533/Graph%20DB/Ontotext/new> Email: vladimir.alexiev@ontotext.com, skype:valexiev1 Mobile: +359 888 568 132, SMS: 359888568132@sms.mtel.net Calendar: https://www.google.com/calendar/embed?src=vladimir.alexiev@ontotext.com Publications and CV: https://github.com/VladimirAlexiev/my
Received on Wednesday, 1 April 2020 08:46:58 UTC