1. On The Evolution of Terms
“appellavitque Adam nominibus suis cuncta animantia et universa volatilia caeli et omnes bestias terrae...“
Genesis, 2:20
Orri Erling - Program Manager, Virtuoso
Yrjänä Rankka - Developer, Virtuoso
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2. “Adam called all things by their names”
We are not the first to try
The history of the "search for the perfect language" favors natural languages
What gets used becomes fit for the task
Language building from scratch has generally not been successful
Forcing nature to fit preconceived, idealized taxonomies has generally failed
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Usage for Linked Data
New layer to the document web
Use de-referenceable HTTP URIs
Use #this to distinguish subject matter from document
Reuse terms where can
Human readable URI's are best
From HTML to XML, most formats are somewhat human readable, same for the data web
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4. Universal “Data Language”?
RDF will do for grammar
Useful vocabulary can only evolve in a community of practice
Distributed evolution of vocabulary and diversity of names for things is a given
Application determines the data structure and vocabulary
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Emerging Hubs
SIOC/FOAF For Web Data Spaces
Dbpedia/UMBEL/OpenCYC for names of real world entities
BFO for epistemology of structures and processes
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6. Can’t Put Genie Back in the Bottle
Once data is out, there it stays
Single identifiers for entities are possible only in closed, application specific DWs
Heterogeneity of names, overlap of descriptions, taxonomies etc is a given
Meaning exists only in context, so make this explicit
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7. Infrastructure Scenarios
Application-specific warehouse or mapped RDBMS
General warehouse with lots of graphs, a la search engine or Billion Triples Challenge
Query driven harvesting a la OpenLink Sponger
On-line discovery and federated SPARQL
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8. Implications for Query
Make it explicit
Report what data sets and SameAs's and graphs went into producing an answer
Allow the app to explicitly choose what graphs, SameAs's, taxonomies, etc. are considered
Search and discoverability will drive vocabulary convergence
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Sameness
SameAs and equivalent are necessary and permanent features
What can be considered identical depends on context
Universal agreement will not happen, so let people choose whose SameAs they trust
SameAs adds query cost and must be resolved at time of query
SameAs cannot be forward chained at web scale because which of them are relevant is not fixed,
Malicious/SPAM SameAs is inevitable
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10. Implications For Publishers
SPARQL and data self description practices are urgently needed
Describe what names are used and what other data meshes with yours
Explicit license
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11. Implications for Entity NS
DNS is good because of distributed, resilient storage and admin
Convergence cannot be forced but should be encouraged
Make administration compartmentalized a la DNS for No SPAM, No censorship
People can say things in their own spaces
Offer classification, e.g. UMBEL
In searching for terms, rank most reused the highest
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Conclusion
Since uniformity is impossible, make diversity of identifiers explicit
Build alongside the document web, de- referenceably and with #this
Encourage reuse but allow innovation
Needs of communities will differ according to stage of development
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Thank You!
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