This document introduces prefLabel.org, a proposed service that provides a simple API to retrieve human-readable labels for URIs from datasets like DBpedia, Wikidata, and Freebase. The service aims to address issues with conventional solutions like URI dereferencing and SPARQL queries by offering fast, best-effort delivery of labels without requiring prior knowledge of the data or dealing with downtime. It has loaded over 58 million labels so far from major datasets and could see uses in applications like the YASGUI SPARQL query tool. The document asks for feedback on how others could use the service and what additional features or datasets it should support.

1. Introducing prefLabel.org
Marat Charlaganov
@charmarat
WAI meeting 27-01-2014, VU Amsterdam

2. Common task: URI -> label
Pattern:
• Use URI’s as names
• Retrieve human-readable labels for (some)
URI’s at a later stage

3. API’s return URI’s

4. Emergent practices

5. Conventional Solutions
• URI dereference
• Guess the SPARQL endpoint
• Use a SPARQL endpoint with loads of triples (e.g.
http://lod.openlinksw.com/sparqrl)

6. Conventional Solutions
• URI dereference
• Guess the SPARQL endpoint
• Use a SPARQL endpoint with loads of triples (e.g.
http://lod.openlinksw.com/sparqrl)
Concerns:
• Non-derefernceable URI’s, constructing a query
requires prior knowledge of the data, postprocessing of the results, downtime, latency

7. Less Conventional
• Sindice API
• …

8. Proposal prefLabel.org
• Best-effort delivery of a single humanreadable label for a given URI
+ Simple API
+ Fast

10. Loaded Data
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DBpedia
Wikidata (using https://github.com/mkroetzsch/wda)
Freebase
~58M labels in total

11. Use case: YASGUI

12. Ideas
• Reverse lookup: label -> URI
• Provenance requests (PROV-AQ?)
• Fetch unknown labels with
conventional methods
• Provide minimal SPARQL interface for
use in federated queries
• …

13. Questions:
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Can YOU use this?
Which datasets to load?
Missing features?
…