Thesaurus-based methods for mapping contents of publication sets

Visualization of literature-related information is common in scientometrics and related fields. Despite this, relatively little work has been done to visualize knowledge organization systems, such as controlled vocabularies or thesauri. In this paper we explore the creation and use of contextual visualizations based on thesauri. Two different methods are developed for creating maps of thesaurus terms that can then be used as templates or basemaps on which to display the contents of publication sets. The first example maps first-level terms from the Unified Astronomy Thesaurus into a wheel-like (hub and spokes) configuration. This circular map can then be used to show relative positions of clusters of astronomy papers from different cluster solutions based on the thesaurus terms assigned to the papers in the clusters. The second example triangulates the entire Public Library of Science (PLOS) thesaurus onto a global map of science, and then uses the resulting map of thesaurus terms as the basis for an overlay map. This map can be used for several purposes, including mapping of subsets of PLOS content, and the identification of thesaurus terms whose rule bases may need to be changed.