Libraries around the world have a long tradition of maintaining authority files to assure the consistent presentation and indexing of names. As library authority files have become available online, the authority data has become accessible -- and many have been published as Linked Open Data (LOD) -- but names in one library authority file typically had no link to corresponding records for persons and organizations in other library authority files. After a successful experiment in matching the Library of Congress/NACO authority file with the German National Library's authority file, an online system called the Virtual International Authority File was developed to facilitate sharing by ingesting, matching, and displaying the relations between records in multiple authority files.
The Virtual International Authority File (VIAF) has grown from three source files in 2007 to more than two dozen files today. The system harvests authority records, enhances them with bibliographic information and brings them together into clusters when it is confident the records describe the same identity. Although the most visible part of VIAF is a HTML interface, the API beneath it supports a linked data view of VIAF with URIs representing the identities themselves, not just URIs for the clusters. It supports names for person, corporations, geographic entities, works, and expressions. With English, French, German, Spanish interfaces (and a Japanese in process), the system is used around the world, with over a million queries per day.
Thomas Hickey is Chief Scientist at OCLC where he helped found OCLC Research. Current interests include metadata creation and editing systems, authority control, parallel systems for bibliographic processing, and information retrieval and display. In addition to implementing VIAF, his group looks into exploring Web access to metadata, identification of FRBR works and expressions in WorldCat, the algorithmic creation of authorities, and the characterization of collections. He has an undergraduate degree in Physics and a Ph.D. in Library and Information Science.