Co-cited author retrieval and relevance theory: examples from the humanities

Abstract

Given a user-selected seed author, a unique experimental system called AuthorWeb can return the 24 authors most frequently co-cited with the seed in a 10-year segment of the Arts and Humanities Citation Index. The Web-based system can then instantly display the seed and the others as a Pathfinder network, a Kohonen self-organizing map, or a pennant diagram. Each display gives a somewhat different overview of the literature cited with the seed in a specialty (e.g., Thomas Mann studies). Each is also a live interface for retrieving (1) the documents that co-cite the seed with another user-selected author, and (2) the works by the seed and the other author that are co-cited. This article describes the Pathfinder and Kohonen maps, but focuses much more on AuthorWeb pennant diagrams, exhibited here for the first time. Pennants are interesting because they unite ego-centered co-citation data from bibliometrics, the TF*IDF formula from information retrieval, and Sperber and Wilson’s relevance theory (RT) from linguistic pragmatics. RT provides a cognitive interpretation of TF*IDF weighting. By making people’s inferential processes a primary concern, RT also yields insights into both topical and non-topical relevance, central matters in information science. Pennants for several authors in the humanities demonstrate these insights.