Analysis of URL references in ETDs: a case study at the University of North Texas

Abstract

Purpose – Increasingly, higher education institutions worldwide are accepting only electronic versions of their students’ theses and dissertations. These electronic theses and dissertations (ETDs) frequently feature embedded URLs in body, footnote and references section of the document. Additionally the web as ETD subject appears to be on an upward trajectory as the web becomes an increasingly important part of everyday life. The paper aims to discuss these issues. Design/methodology/approach – The authors analyzed URL references in 4,335 ETDs in the UNT ETD collection. Links were extracted from the full-text documents, cleaned and canonicalized, deconstructed in the subparts of a URL and then indexed with the full-text indexer Solr. Queries to aggregate and generate overall statistics and trends were generated against the Solr index. The resulting data were analyzed for patterns and trends within a variety of groupings. Findings – ETDs at the University of North Texas that include URL references have increased over the past 14 years from 23 percent in 1999 to 80 percent in 2012. URLs are being included into ETDs in the majority of cases: 62 percent of the publications analyzed in this work contained URLs. Originality/value – This research establishes that web resources are being widely cited in UNT's ETDs and that growth in citing these resources has been observed. Further it provides a preliminary framework for technical methods appropriate for approaching analysis of similar data that may be applicable to other sets of documents or subject areas.

Reference Rot in the Repository: A Case Study of Electronic Theses and Dissertations (ETDs) in an Academic Library

“…Links were mined from the body of the text in a manner similar to the study carried out at UNT. 34 We wanted a regular expression which would catch as many URLs as possible, expecting to manually clean the link output before further processing. We tested multiple regular expressions 35 against a small sample of our converted ETDs and compared the results.…”

“…4 Since an ETD comprises a unique form of scholarly output produced by universities, and simultaneously satisfies the parent institution's degree-granting apparatus, as well as reflecting its academic stature on the international stage, the presence of reference rot in this body of literature is of particular concern and worthy of immediate attention.…”

“…24 The team analyzed 26,683 unique URLs in 2,713 ETDs containing one or more links, finding an overall average of 10.58 unique URLs per ETD with one or more links. The UNT team provided a breakdown of domain and subdomain occurrence frequency, and indicated areas of future investigation into content-based URL linking patterns of ETDs.…”