Web intelligence analyses of digital libraries: A case study of the National electronic Library for Health (NeLH)

Purpose – To explore the use of LexiURL as a Web intelligence tool for collecting and analysing links to digital libraries, focusing specifically on the National electronic Library for Health (NeLH). Design/methodology/approach – The Web intelligence techniques in this study are a combination of link analysis (web structure mining), web server log file analysis (web usage mining), and text analysis (web content mining), utilizing the power of commercial search engines and drawing upon the information science fields of bibliometrics and webometrics. LexiURL is a computer program designed to calculate summary statistics for lists of links or URLs. Its output is a series of standard reports, for example listing and counting all of the different domain names in the data. Findings – Link data, when analysed together with user transaction log files (i.e., Web referring domains) can provide insights into who is using a digital library and when, and who could be using the digital library if they are “surfing” a particular part of the Web; in this case any site that is linked to or colinked with the NeLH. This study found that the NeLH was embedded in a multifaceted Web context, including many governmental, educational, commercial and organisational sites, with the most interesting being sites from the .edu domain, representing American Universities. Not many links directed to the NeLH were followed on September 25, 2005 (the date of the log file analysis and link extraction analysis), which means that users who access the digital library have been arriving at the site via only a few select links, bookmarks and search engine searches, or non-electronic sources. Research limitations/implications – LexiURL uses the Yahoo! API for its link extraction, but the use of commercial search engine data has several limitations. First, no search engine covers the entire web and so all are likely to return incomplete results. This problem is exacerbated by the typical limitation of 1,000 results per query and for Google and Yahoo! and their automatic search services report only a fraction of the results known by the parent search engine. Hence for a large digital library, LexiURL could be expected to find perhaps only 10% or less of the links to the site. A second limitation is that the method by which each search engine finds pages is unknown, as is the method for ranking results. Originality/value – A number of studies concerning digital library users have been carried out using log file analysis as a research tool. Log files focus on real-time user transactions; while LexiURL can be used to extract links and colinks associated with a digital library’s growing Web network. This Web network is not recognized often enough, and can be a useful indication of where potential users are surfing, even if they have not yet specifically visited the NeLH site.