Improving WorldCat quality
OCLC’s WorldCat approaches 475 million bibliographic records. Many of those records have been created manually by members of OCLC’s worldwide cooperative. Others have been added to WorldCat en masse from institutions large and small, from national libraries, from cultural heritage institutions, or from rural public libraries. The focus of this article is quality control of the bibliographic database, historically and currently, in four interrelated aspects: keeping OCLC-MARC validation in harmony with an ever-changing MARC 21, the specific effort to phase out OCLC-defined Encoding Levels in favour of those defined in MARC 21, a history of the automated Duplicate Detection and Resolution (DDR) software, and our work on updating Bibliographic Formats and Standards (BFAS) as reflected in Chapter 4 »When to Input a New Record«.