Revisiting the syntactical and structural analysis of Library of Congress Subject Headings for the digital environment

Tirilly

Leide

et al. 2012

J Am Soc Inf Sci Tec

The Library of Congress Subject Headings (LCSH) is a subject structure used to index large library collections throughout the world. Browsing a collection through LCSH is difficult using current online tools in part because users cannot explore the structure using their existing experience navigating file hierarchies on their hard drives. This is due to inconsistencies in the LCSH structure, which does not adhere to the specific rules defining tree structures. This article proposes a method to adapt the LCSH structure to reflect a real‐world collection from the domain of science and engineering. This structure is transformed into a valid tree structure using an automatic process. The analysis of the resulting LCSH tree shows a large and complex structure. The analysis of the distribution of information within the LCSH tree reveals a power law distribution where the vast majority of subjects contain few information items and a few subjects contain the vast majority of the collection.

Section: Methodssupporting

confidence: 92%

Constructing a true LCSH tree of a science and engineering collection

Tirilly

Leide

et al. 2012

J Am Soc Inf Sci Tec

“…There are 20,791 MeSH descriptors assigned to the collection of 233,388 bibliographic records, and 18,318 LCSHs assigned to a collection comprising 122,197 bibliographic records housed in the McGill Schulich Science and Engineering library . The subset of LCSH representing the domain of science was selected for this study because it offers the most complex portion of the LCSH structure (Julien et al., ; Yi & Chan, ). Some subject headings not assigned to documents are required to connect the tree fully from the most general down to the most specific subjects.…”

Section: Methodsmentioning

confidence: 99%

“…Data set characteristics. The subset of LCSH representing the domain of science was selected for this study because it offers the most complex portion of the LCSH structure(Julien et al, 2012a;Yi & Chan, 2010). Some subject headings not assigned to documents are required to connect the tree fully from the most general down to the most specific subjects.…”

mentioning

confidence: 99%

Reducing subject tree browsing complexity

Tirilly

Dinneen

et al. 2013

J Am Soc Inf Sci Tec

Many large digital collections are currently organized by subject; although useful, these information organization structures are large and complex and thus difficult to browse. Current online tools and visualization prototypes show small, localized subsets and do not provide the ability to explore the predominant patterns of the overall subject structure. This study describes subject tree modifications that facilitate browsing for documents by capitalizing on the highly uneven distribution of real‐world collections. The approach is demonstrated on two large collections organized by the Library of Congress Subject Headings (LCSH) and Medical Subject Headings (MeSH). Results show that the LCSH subject tree can be reduced to 49% of its initial complexity while maintaining access to 83% of the collection, and the MeSH tree can be reduced to 45% of its initial complexity while maintaining access to 97% of the collection. A simple solution to negate the loss of access is discussed. The visual impact is demonstrated by using traditional outline views and a slider control allowing searchers to change the subject structure dynamically according to their needs. This study has implications for the development of information organization theory and human–information interaction techniques for subject trees.

“…Our dataset is comprised of 1) a collection of 122,197 bibliographic records housed at McGill University's Schulich Library of Science and Engineering, and 2) its roughly 205,000 LCSH authority records. The domain of science was selected as an extreme test for this study since it offers the deepest and most connected portion of the LCSH structure (Julien, Tirilly, Leide, & Guastavino, 2012;Yi & Chan, 2010).…”

Section: Datasetsmentioning

confidence: 99%

Library of congress subject heading (LCSH) browsing and natural language searching

Proc. Assoc. Info. Sci. Tech.

Asadi

Dinneen

et al. 2016

Controlled topical vocabularies (CVs) are built into information systems to aid browsing and retrieval of items that may be unfamiliar, but it is unclear how this feature should be integrated with standard keyword searching. Few systems or scholarly prototypes have attempted this, and none have used the most widely used CV, the Library of Congress Subject Headings (LCSH), which organizes monograph collections in academic libraries throughout the world. This paper describes a working prototype of a Web application that concurrently allows topic exploration using an outline tree view of the LCSH hierarchy and natural language keyword searching of a real-world Science and Engineering bibliographic collection. Pilot testing shows the system is functional, and work to fit the complex LCSH structure into a usable hierarchy is ongoing. This study contributes to knowledge of the practical design decisions required when developing linked interactions between topical hierarchy browsing and natural language searching, which promise to facilitate information discovery and exploration.