Citation Searching and Bibliometric Measures Resources for Ranking and Tracking

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internet resources Robin Kear and Danielle Colbert-Lewis Citation searching and bibliometric measures Resources for ranking and tracking

A professor asks you, “Who is citing my watch and continues to produce beautiful articles? How many times have I been cited? data visualization projects. What is my h-index score?” A student asks you, “How do I know if this Citation tools and measures article is important?” • Citation Map. Web of Knowledge cre- Another professor asks you, “Which jour- ated this tool that depicts backwards and nal should I publish in for my tenure?” forwards citation of an article using a map A different student asks you, “What are format. The backwards feature represents the the best journals in the field of Anthropology?” citations in the current selected document, and the forward feature represents the documents he avenues to evaluate citation track- that have cited the current selected document. Ting and journal ranking have greatly This tool gives dynamic representation of the increased in the past six years. Bibliometrics, impact that a document has on a field, a topic the application of mathematical and statistical area, or trend. Access: http://wokinfo.com. analysis to books, journals, and other publica- • Citation Reports. This tool by Web tions,1 allows us to choose journal collections, of Knowledge, gives a graphical presenta- assist with applications for research funding, tion and snapshot of a set of articles. Upon evaluate journal status, and find significant conducting a search (by topic, author, or contributors in a subject area. Most impor- publication name) and selecting a group of tantly, the expertise librarians have in this documents, users will find a link to Web of area can be used to help our faculty prove Knowledge to Create Citation Reports. The their scholarly contribution and achieve suc- report includes graphs for Published Items cess in their tenure process. in Each Year and Citations in Each Year. The Any aggregator of citations could create its Results Found section of the report details own bibliometric measures if they are willing the Sum of times cited, Sum of times cited to invest the time and expense. Elsevier and without self-citations, Citing articles, Average Thomson Reuters are the major players in citations per item, and the h-index. Citation creating citation and journal measures. Each Reports serves as a helpful tool as it helps vendor primarily uses its own unique data, users to understand various trends of a topic, journals, publications, authority files, indexes, how an author has published over time, and and subject categories. Both companies have the most cited articles related to that search given their data to research labs to create new topic. Access: http://wokinfo.com. metrics that are freely available online from the labs and are also included in the com- Robin Kear is reference/instruction librarian at University pany’s products for subscribers. One metric, of Pittsburgh’s Hillman Library, e-mail: [email protected], the h-index, is vendor neutral but there is no and Danielle Colbert-Lewis is reference librarian at the James E. Shepard Memorial Library at North Carolina overarching tool that exists across vendors. Central University, e-mail: [email protected] The bibliometrics field is an exciting one to © 2011 Robin Kear and Danielle Colbert-Lewis

C&RL News September 2011 470 • Citation Tracker. This Scopus product h-index presented by conducting a search gives detailed information on finding, check- and selecting an author’s hyperlinked name ing, and tracking citations. Upon conducting under the Research section. Access: Web of a search and selecting a group of documents Knowledge at http://www.wokinfo.com and in Scopus, Citation Tracker, displayed under Scopus at http://www.info.sciverse.com/ the View Citation Overview page, gives users scopus. an overview of how many times a selected document has been cited upon its initial selec- Subscription databases for citation tion, and the number of documents that cited searching the selected document since 1996 and the • Academic Search Premier. This da- h-index. This citation overview information tabase by EBSCOhost has a few tools that assists researchers by helping them evaluate allow researchers to search for citation ef- the currency and impact of research overtime. fectively. These tools include Find Similar Re- Access: http://www.info.sciverse.com/scopus. sults, Cited References, and Citation Matcher. • h-graph. Scopus’s h-graph visually de- The Find Similar Results feature uses Smart- picts the impact of an author’s research or set Text Searching to find other documents that of articles. By selecting h-graph, users have share a relation to the original article. By a choice of three different graphs to view or conducting a Cited Reference search, the select: the h-index, articles published, and user receives a list of articles that cite the citations. Users will also see these graphs original article. Located under the More op- under the author’s name or by conducting a tion feature in Academic Search Premier (top document search. At the end of the search, menu bar), the Citation Matcher feature al- the user then selects an author’s hyperlinked lows researchers to search for specific works. name under the research section via a view Access: http://www.ebscohost.com/academic h-graph link. Access: http://www.info.sciverse. /academic-search-premier. com/scopus. • Google Scholar. Google Scholar has the • h-index. J. E. Hirsch created the h- Cited By feature, which allows researchers to index in his 2005 paper titled “An index to see how many times a document has been quantify an individual’s scientific research cited. At the conclusion of a search, the results output.” In this foundational paper, Hirsch show the number of times that both articles tries to answer the question, “[H]ow does and documents have been cited. This feature one quantify the cumulative impact and rel- helps researchers get a preliminary idea of the evance of an individual’s scientific research articles and research that make an impact in a output?” In the abstract, Hirsch proposes that field of interest. Google has a new tool called the index h, defined as the number of papers Google Scholar Citations that will create a pub- with citation number ≥h, serves as a useful lic profile for users that includes their citation index to characterize the scientific output of metrics as calculated by Google. This feature is a researcher. currently in testing with a small group of users. The h-index measures the broad impact Keep in mind that Google Scholar includes of a researcher’s work. When conducting re- citations from an array of sources in its cited by search for the aforementioned article, the data calculations, including Microsoft PowerPoint focused primarily on physicists, however the and Word documents, and gives everything an data has proven applicability to other areas equal rank. Access: http://scholar.google.com of sciences and more recently to humanities. and for more information on the new Scholar Web of Knowledge and Scopus both include Citations see http://scholar.google.com/intl the h-index in searches for an author. In Web /en/scholar/citations.html. of Knowledge, a user finds the h-index under • JSTOR. JSTOR, by ITHAKA, has two the Citation Reports section at the beginning search options: the Citation Locator and of a search. In Scopus, the user will find the Advanced Search. These tools serve as good

September 2011 471 C&RL News options for researchers that know of a journal’s Journal tools and measures accessibility in JSTOR and have citation infor- • Article Influence Score. This score mation available. Citation Locator takes you came out of the same project by Carl Berg- directly to the article. Once the user selects strom’s team at University of Washington as a document from a search, he or she has the Eigenfactor and uses Thomson Reuters JCR option to use the Google Scholar feature Items citation data. It calculates the relative impor- Citing regarding the citation of the search item. tance of a journal on a per-article basis. It is the By selecting this feature, a search will be run journal’s Eigenfactor Score divided by the frac- in Google Scholar for articles citing the original tion of articles published by the journal. That target article. Users have another feature in JS- fraction is normalized so that the sum total of TOR at their disposal called Track Citations. By articles from all journals is 1. A score greater selecting this feature, users receive an e-mail than 1.00 indicates that each article in the when another article in JSTOR cites the original journal has above-average influence. A score target article. Access: http://about.jstor.org. less than 1.00 indicates that each article in the • PsycINFO. Produced by the American journal has below-average influence. Access: Psychological Association, PsycINFO has the More information, including visualization of Find Citation feature as one of the search the data, and scores for certain years are avail- options on the main search page. This tools able freely through the Eigenfactor Web site works well when the researcher has detailed at http://www.eigenfactor.org and/or through citation information accessible to enter into the the Journal Citation Reports subscription search. Access: http://www.apa.org/psycinfo. database available from Thomson Reuters at • Scopus. This Elsevier database contains http://thomsonreuters.com/products_services the Citation Tracker in the View Citation Over- /science/science_products/a-z/journal view area and the number of times a document _citation_reports/. has been cited within that overview, and also • Eigenfactor Score. This score came the h-index. Another feature of Scopus called out of the Metrics Eigenfactor Project, a bib- Related Documents shows documents that liometric research project conducted by Carl have shared references. Following a user’s Bergstrom and his laboratory at the Univer- search and selection of a document, the Re- sity of Washington. The Eigenfactor Score lated Documents feature allows the researcher uses Thomson Reuters JCR citation data and to find other documents that have shared measures the number of times articles from references, author, and/or keywords. Access: the journal published in the past five years http://www.info.sciverse.com/scopus. have been cited in the JCR year. Similar to • Web of Knowledge. This database by the Impact Factor, the Eigenfactor Score is es- Thomson Reuters offers search tools like Cited sentially a ratio of the number of citations to Reference Search in order to directly access spe- total number of articles. However, unlike the cific documents. Moreover, once a user chooses Impact Factor, the Eigenfactor Score counts the a search in conducted and document, the Times citations to journals in both the sciences and Cited tool helps users to see how many other social sciences, eliminates self-citations, and documents have cited the originally selected weights each reference according to a stochas- document. Users may also view the Times tic measure of the amount of time researchers Cited on the search page and the h-index. All spend reading the journal. Eigenfactor scores of these features benefit researchers by helping are scaled so that the sum of the Eigenfactor them evaluate the significance of a document scores of all journals listed in Thomson’s JCR to a topic, a field of study, or a trend. Access: is 100. The top 1,000 journals, as ranked by http://wokinfo.com. Eigenfactor score, all have scores above 0.01. Access: More information, including visualization of the data, and scores for certain years are available freely through the Eigenfactor

C&RL News September 2011 472 Web site at http://www.eigenfactor.org and/ ment measure that is the number of citations or scores are included as part of the Journal received by a journal divided by the number Citation Reports subscription database avail- of citations in that journal for the three previ- able by subscription from Thomson Reuters at ous years. SJR then weights the citations with http://thomsonreuters.com/products_services a prestige metric that normalizes across the /science/science_products/a-z/journal citation behavior of different journals. Ac- _citation_reports/. cess: http://www.scimagojr.com/index.php and http://www.journalmetrics.com and/or through the Scopus subscription database available from Elsevier at http://www.info. sciverse.com/scopus. • SNIP (Source Normalized Impact • Impact Factor. The Impact Factor is per Paper). SNIP was developed by Henk certainly the longest and most well-known Moed at the CWTS (Centre for Science and journal measure. Eugene Garfield first had Technology Studies) of Leiden University in the idea for the measure in 1955, and it was the Netherlands using Elsevier citation data published as part of the Science Citation Index from Scopus. SNIP also starts with a basic in 1961. The journal Impact Factor is the aver- per peer-reviewed document measure that is age number of times articles from the journal the number of citations received by a journal published in the past two years have been divided by the number of citations in that cited in the Journal Citation Reports (JCR) journal for the three previous years. SNIP year using Thomson Reuter’s citation data. An then considers the citations in the context in Impact Factor of 1.0 means that, on average, which they are made (the journal), including the articles published one or two years ago a citation’s potential (or how likely it is to be have been cited one time. Citing articles may cited) that normalizes across disciplines. Ac- be from the same journal; however, most cit- cess: http://www.journalindicators.com and ing articles are from different journals. Access: http://www.journalmetrics.com or through the Through the subscription database Journal Scopus subscription database at http://www. Citation Reports, available from Thomson Re- info.sciverse.com/scopus. uters at http://thomsonreuters.com/products _services/science/science_products/a-z /journal_citation_reports. • Journal Analyzer Tool. In Scopus, this tool provides a view of journal performance using Elsevier citation data. Using citations from nearly 18,000 titles from 5,000 inter- national publishers, the Journal Analyzer has Subscription databases for journal scores from 1999 forward. The journal analyzer measures charts the SJR score, SNIP score, total number of • InCites. This Thomson Reuters database citations received by the journal, total number is a citation-based research evaluation tool of of documents of the journal, and the percentage people, programs, and peers. Bibliometrics of documents that are not cited from that year. included in the analysis are total papers, total Access: http://www.info.sciverse.com/scopus. citations, citation impact (cites per paper), • SJR (SCImago Journal Rank) percent cited and uncited papers, collabora- Score. This score was created by the SCImago Lab and Professor Felix de Moya- Anegon at the University of Granada in Spain using Elsevier citation data from Scopus. SJR starts with a basic per-peer-reviewed docu-

September 2011 473 C&RL News tion indicators, expected citation count, • Web of Knowledge. From Thomson expected citation rates for category, mean/ Reuters, Web of Knowledge is a platform median citation, h-index score, citation fre- that includes the sciences, social sciences, quency distribution, source article rankings, arts and humanities journals, and conference and citation articles rankings. Access: http:// proceedings. The platform can include Web thomsonreuters.com/products_services of Science and Journal Citation Reports, /science/science_products/a-z/incites/. depending on the institution’s subscriptions. • Journal Citation Reports. This Thom- Citation metrics included are h-index score, son Reuters database can be accessed sepa- citation reports, citation mapping, citing rately or through the ISI Web of Knowledge articles, and sums and averages of citations. platform. The database is the only way to Access: http://wokinfo.com. access the Impact Factor metrics, and it also includes the Eigenfactor and Article Bibliography Infl uence scores, fi ve-year Impact Factor, • Bergstrom, C. (2007). “Eigenfactor: and the immediacy index. The Sciences Measuring the value and prestige of scholarly Edition covers more than 6,500 journals; journals.” College and Research Libraries the Social Sciences Edition covers more News 68 (5), 314-316. Retrieved 7/14/2011 than 1,900, both from 1997 forward. Access: from http://www.ala.org/ala/mgrps/divs Pricing and sales contact information at /acrl/publications/crlnews/2007/may http://thomsonreuters.com/products /eigenfactor.cfm _services/science/science_products/a-z • Garﬁ eld, E. (2006). “The history and /journal_citation_reports. meaning of the journal impact factor,” • Scopus. Scopus, from Elsevier, is a JAMA: The Journal of the American Medi- database that includes coverage of scien- cal Association 295(1), 90-93. doi:10.1001/ tifi c, technical, medical, and social science jama.295.1.90. journals and conference proceedings. The • Gonzalez-Pereira, B., Guerrero-Bote, V. bibliometrics included are h-index score, h- and Moya-Anegon, F. (2009). “The SJR indi- graph, citation tracker, journal analyzer, and cator: A new indicator of journals’ scientifi c SNIP and SJR journal scores. Access: http:// prestige,” retrieved 7/14/2011 from http:// www.info.sciverse.com/scopus. arxiv.org/abs/0912.4141. • Hirsch, J. E. (2005). An index to quantify an individual’s scientifi c research output. Proceedings of the National Academy Further viewing of Sciences of the United States of Amer- ica, 102 (46), 16569-16572. doi:10.1073/ • Web of Knowledge Training You- pnas.0507655102. Tube Channel. Watch Thomson Reuter’s • Moed, H. F. (2009). Measuring con- WoK (Web of Knowledge) channel for textual citation impact of scientifi c journals, short videos on citation counts, cited reference searching, and citation reports retrieved 7/14/2010 from http://arxiv.org features available through the subscription /abs/0911.2632. database. Access: http://www.youtube. com/user/WoKtraining. Notes • ScopusTV YouTube Channel. 1. Oxford University Press. (2011, Watch Elsevier’s ScopusTV channel for June). Bibliometrics, n. Retrieved 7/23/11, short videos on the h-index, SNIP, and SJR from OED Online, www.oed.com/view scores available through the subscription /Entry/241665. database. Access: http://www.youtube. 2. Please visit the bibliometrics LibGuide com/user/ScopusTV. they created together at pitt.libguides.com /bibliometrics.

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