Citation tracking of scientific publications through two different searching tools : Google scholar and Web of science

摘要

Citation analysis has been used since the mid-20th century as a tool to measure impact andvisibility of scientific articles, to monitor a subject trend, and to evaluate the scientific impact ofa given researcher or institution. Although it has been recognized as an often inappropriatelyapplied practice, the impact factors of journals in which authors publish are still employed inmany countries to evaluate the performance of an author or of a research group in order toaward grants or government funding.The purpose of this presentation is to assess similarities and differences in citation trackingof scientific publications of two searching tools: Google Scholar (GS) and Web of Science(WoS).Google Scholar http://scholar.google.com is a free-of-charge search engine aimed atfinding scholarly information on the Web, available in its beta version since November 2004.Its search includes bibliographic references and the full-text of peer-reviewed papers, theses,books, abstracts, technical reports. The special feature of Google Scholar is its "cited by" optionwhich provides searchers with links to other articles that have cited the paper being viewed; itssearch engine automatically extracts and analyzes citations and presents them as separateresults, giving links to the full-text of the articles as present on the Web.Thomson Web of Science http://scientific.thomson.com/webofknowledge/wosgenben.htmlis a subscription-based multidisciplinary database covering scientific literature from about6,125 journals dating from as far back as 1945. It’s a valuable and well-known tool forexhaustive research. The feature "cited reference" enables users to find articles that cite apreviously published work.Two samples of articles published on scientific journals in the year 2002 were examined toevaluate the number of citations received by each article over the 2002- 2006 period, both in GSand in WoS. An analysis of unique and overlapping citations was performed.Results show that retrieval of citations found in Web of Science was higher in 2005 than inGoogle Scholar, while in 2006 the amount of citations retrieved has been almost equal.Since resulting citations do not match exactly, due to the difference in type ofdocumentation considered by search algorithms, the two instruments can be seen ascomplementary, although a high percentage of overlapping material results from this research.