Scrolling past the Royal Flying Doctor Service website for the 100th time as I Google for the RDF Schema documentation
Scrolling past the Royal Flying Doctor Service website for the 100th time as I Google for the RDF Schema documentation
@multimeric I think they serve different purposes. #rdfs is not really a schema language, at least not in the "here is a prescribed structure you can validate against" sense. It was more intended as a descriptional thing, something to define basic vocabulary ("my model is about kinds of vehicles, like cars, and bikes"). A lightweight ontology language if you will. SHACL is about setting structure constraints, and data validation. They're complementary IMO.
RDF people: why does everyone still use RDFS and not SHACL for writing schemas, when all the actual validation tools are for SHACL?
Are there even any RDFS validators? I can't find any.
Le Programme IA chez Inria recrute dans le Projet P16 un Ingénieur développeur Senior Java pour la bibliothèque Corese (linked data, knowledge graphs, web sémantique)
Candidatez ici : http://jobs.inria.fr/public/classic/fr/offres/2025-08596
#RDF #RDFS #OWL #SHACL #SPARQL #LinkedData #WebSem #KnowledgeGraphs
#Jobs.inria.fr #Emploi #SophiaAntipolis #Job
In the #ISE2024 lecture today, we will discuss RDF as basic building block for the Web of Data.
slides: https://drive.google.com/file/d/1gJ3RD3Sz2JuEpCF-mBBfA85boYP_jrON/view?usp=drive_link
#semanticweb #knowledgegraphs #rdf #rdfs #WebOfData @fizise @MahsaVafaie @enorouzi @shufan @sourisnumerique
Using IndeGx and our endpoint catalog, I surveyed the usage of #RDF, #RDFS, #OWL, #SWRL, #SHACL, #SPIN, and #SKOS over 320 endpoints.
Some insights:
- Only 2 endpoints do not use RDF, one seems to have gone down during tests, and the other uses only Schema
- 11 endpoints use exclusively RDF
- Endpoints use an average of 3.8 of the listed vocabularies
- By far, the most used are RDF, RDFS, OWL and SKOS
- All vocabularies are used together at least once
More details to follow
#linkeddata #sparql
@hrefna you're so deeply right in this thread. this essentially defines the early and formative years of #RDF and #RDFS around some key decisions. There is so much worry about errors from mishandling, but the very possibility of expressing something that could be wrong. There is so much here it's hard to even know where to start but from the very start of the rdf-core and especially rdf-logic mailing lists the emphasis on correctness of expression vs. agency of interpretation is heated. This is a pretty unsubtle example: https://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001Nov/0423.html
"Summary: RDF is not just a data model. The RDF specs should define a semantics so that an RDF statement on the web is interpreted as an assertion of that statement such that its author would be responsible in law as if it had been published in, say, a newspaper."
affirmed by this text: https://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jun/0180.html
"The RDFCore WG takes the view that RDF/XML documents, ie. encodings of
RDF graphs, are represenations of claims or assertions about the world. [...] we note that RDF graphs are the kind of things that can be true or false (rather than 'mere bytes'). For each linear syntax of RDF, there will be conventions (social, legal) for indicating which chunks of data are encodings of RDF graphs in that syntax, and thus of propositional content."
So ya very very early they had decided that RDF was intended to be platonic representation of the world - it is a method of making propositions that must directly bear on the world, there is no ambiguity, there are only true or false things. (There's a lot of subtlety in that but yno.)
Another thing that comes to mind is the discussion of monotonicity that happens throughout, that's also tied up with the discussion of closed worldedness, containers, and whether or not things belong in sets for the purpose of local meaning or need to belong to the One Great Uniform Graph. It must be impossible for adding new triples into the reasoner to make it less certain of some outcome (ie. if it was possible for ambiguity to be introduced eg. by tangled type hierarchies etc.). This thread is all very illustrative but this message is super spicy and also touches on what you're talking about re using the level of granularity you care about: https://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001Nov/0363.html
this quote from D bricks is also pretty telling of the epistemological commitments:
"RDF Schema is not about policing the content of specific descriptions
'what is said'; it's about policing what is sensibly sayable."
In the next section in this week's #kg2023 online lecture you will learn about vocabularies and how to design simple models with the RDF Schema Description Language RDFS.
video lecture: https://open.hpi.de/courses/knowledgegraphs2023/items/2fLyYCsLoiikZJCuCjjspY
#OpenHPI @fiz_karlsruhe @fizise @tabea @sashabruns @enorouzi #knowledgegraphs #mooc #lecture #semanticweb #rdf #rdfs #startrek
Announcing Aidan Hogan and Sebastian Rudolph for the first tutorial session on querying and reasoning on #knowledgegraphs at #isws2023
Q: What is a Language? A: Read: #RDF #SPARQL #SQL #OWL #RDFS #SemanticWeb #LinkedData #SmartData #OpenData #BigData