TF-Graphs/Workshop

Workshop results

Suggestions called "Graph Identification" from Stanford Workshop are reproduced below.

Pros

• widely used by the community
• part of SPARQL already
• numerous use cases
• clarify confusion in implementation

Cons

• adds complication and may not solve the issue nevertheless
• complicates the RDF model (potentially)
• risks with backward compatibility should be assessed (e.g., syntax)
• does it need standardization?

Proposals

• Named graphs, provenance and trust , Jeremy Carroll, Christian Bizer, Patrick Hayes, Patrick Stickler, WWW 2005, http://www.w3.org/2009/12/rdf-ws/p613.pdf, http://www4.wiwiss.fu-berlin.de/bizer/SWTSGuide/carroll-ISWC2004.pdf
• Quadstores in general
• ODM RDF Metamodel (see http://www.omg.org/spec/ODM/1.0/, section 10.5, derived from Carroll et al.)
• Michel Chein and Marie-Laure Mugnier. Positive nested conceptual graphs. In Proceedings of ICCS '97, volume 1257 of LNAI, pages 95-109, Springer, 1997. (http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.30.3644) ; Nested Graphs: A Graph-based Knowledge Representation Model with FOL Semantics (1998) ( http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.37.5256 )
• SPARQL Specifications (RDF Datasets) and related to that, Axel's proposal to base the work on RDF Datasets (see IRC)
• Notation 3, Tim Berners-Lee, 1998 http://www.w3.org/DesignIssues/Notation3
• ideas from the Topic Maps work (see also SWBPD WG note, http://www.w3.org/TR/rdftm-survey/)
• “Triplesets: Tagging and Grouping in RDF Datasets”, http://www.w3.org/2009/12/rdf-ws/papers/ws24, Atanas Kiryakov, Vassil Momtchev
• hypergraphs (as a general mathematical domain)

Technical Issues

• mutual roles of quads vs. singleton named graphs vs. named graphs
• extension the RDF(S) semantics?
• new RDF(S) terms? rdf:Graph, rdf:subGraphOf, rdf:equivalentGraph, etc.
• syntax (TRIG, INRIA Member submission, Web, Graphs and Semantics , n3)
• graph inclusion, can named graphs share triples
• whether blank nodes can be shared among multiple graphs
• whether blank nodes can be used as graph names
• named graphs do not fully replace reification
• how would follow your nose apply to named graphs?
• relationships to SPARQL
• effects on the SW stack
• how does it influence the OWL semantics?