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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, VirtuosoYrjänä Rankka - Developer, Virtuoso

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“Adam called all things by their names”

We are not the first to tryThe history of the "search for the perfect language"

favors natural languagesWhat gets used becomes fit for the taskLanguage building from scratch has generally not

been successfulForcing nature to fit preconceived, idealized

taxonomies has generally failed

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Usage for Linked Data

New layer to the document webUse de-referenceable HTTP URIsUse #this to distinguish subject matter from

documentReuse terms where canHuman readable URI's are bestFrom HTML to XML, most formats are somewhat

human readable, same for the data web

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Universal “Data Language”?

RDF will do for grammar Useful vocabulary can only evolve in a

community of practiceDistributed evolution of vocabulary and

diversity of names for things is a givenApplication determines the data structure and

vocabulary

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Emerging Hubs

SIOC/FOAF For Web Data SpacesDbpedia/UMBEL/OpenCYC for names of real

world entitiesBFO for epistemology of structures and

processes

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Can’t Put Genie Back in the Bottle

Once data is out, there it staysSingle identifiers for entities are possible only

in closed, application specific DWs Heterogeneity of names, overlap of

descriptions, taxonomies etc is a givenMeaning exists only in context, so make this

explicit

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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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Implications for Query

Make it explicitReport what data sets and SameAs's and

graphs went into producing an answerAllow 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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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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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 spacesOffer 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 innovationNeeds of communities will differ according to

stage of development

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OpenLink Software

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