Errors and Obsolete Elements in Assigned Library of Congress Subject Headings: Implications for Subject Cataloging and Subject Authority Control

Abstract

An analysis of a sample of 9,442 headings assigned by the Library of Congress (LC) to bibliographic records disclosed two types of invalid headings: those that were erroneous and those that were obsolete. Each type revealed recurring patterns. Errors and obsolete elements occurring in assigned headings involve MAchine Readable Cataloging (MARC) coding, terminology in main headings and subdivisions, application of subdivisions, and in mechanical elements such as punctuation and capitalization. Different headings (e.g., personal name, corporate name, topical, etc.) display different patterns as well as predominance of errors and obsoleteness. Although the overall error rate is low, an awareness and understanding of patterns of errors and obsolescence in subject heading strings should contribute to improvement in subject heading assignment and subject authority control.