JOURNAL CITATION REPORTS ® “THE JCR” Jon Stroll, Key Account Manager January 2011

Agenda: The Data The JCR The Enhancements Use and Misuse

A BRIEF HISTORY OF THE CITATION INDEX Concept first developed by Dr Eugene Garfield –Science, 1955 The Science Citation Index (1963) –SCI print (1960’s) –On-line with SciSearch in the 1970’s –CD-ROM in the 1980’s –Web interface (1997) Web of Science Content enhanced: –Social Sciences Citation Index (SSCI) –Arts & Humanities Citation Index (AHCI) The Citation Index –Primarily developed for purposes of information retrieval –Development of electronic media and powerful searching tools have increased its use and popularity for purposes of Research Evaluation

THE VALUE OF A CITATION Why do people cite? –Pay homage / give credit to pioneer –Identifying a methodology –Provide background reading –Quotations –Authenticating data, reproducing work etc –Corrections –Criticizing/Disclaiming someone's work/opinions Citations are an indicator of an article’s impact and usefulness to the research community; they are the mode by which peers acknowledge each other’s research. The value of a citation is only as important as its source. –Clearly a citation from a prestigious peer review journal has more value than a citation from non-scholarly material. –How can you be sure that the citing source is reputable? “When to Cite”, E. Garfield, Library Quarterly, v66, p , 1996

WHY NOT INDEX ALL JOURNALS? 40% of the journals: 80% of the publications 92% of cited papers 4% of the journals: 30% of the publications 51% of cited papers

HOW DO WE DECIDE WHICH JOURNALS TO INDEX? Approx journals evaluated annually –10-12% accepted Thomson Reuters editors –Information professionals –Librarians –Experts in the literature of their subject area Web of Science Journals under evaluation Journal ‘quality’

THOMSON REUTERS JOURNAL SELECTION POLICY Publishing Standards –Peer review, Editorial conventions Editorial content –Addition to knowledge in specific subject field Diversity –International, regional influence of authors, editors, advisors Citation analysis –Editors and authors’ prior work

Region# Journals from Region in Web of Science Europe5,573 49% North America4,251 38% Asia-Pacific965 9% Latin America272 2% Middle East/Africa200 1% Language# Journals in Web of Science English % Other % GLOBAL RESEARCH REPRESENTATION WEB OF SCIENCE COVERAGE

Agenda: The JCR

A DEFINITION: JOURNAL IMPACT FACTOR 2009 Impact Factor Source paper – published in 2009 Cited reference – published in 2007 or 2008 Citations All Previous Years

CALCULATING 2009 JOURNAL IMPACT FACTOR HEALTH ECONOMICS Citations in 2009 To items published in 2008 = 156 To items published in 2007 = 210 Sum = 366 Number of items Published in 2008 = 97 Published in 2007 = 85 Sum = = 2.011

Agenda: The Enhancements

Why add additional metrics to the JCR? Our objective in including this new information is to expand one’s evaluative perspective on scholarly journals, to provide a more thorough and well-rounded overview of their overall impact and influence. Journal Citation Reports ® – Enhancements

New Metrics & Information Five-Year Impact Factor Rank-in-Category Tables Box Plots Illumination of Journal Self-Citations Eigenfactor Metrics TM : Eigenfactor TM and Article Influence TM Journal Citation Reports ® – Enhancements

Citation Behavior, variance among disciplines : Some fields are very fast moving, particularly within the life sciences, and published research gets cited at a relatively rapid pace. Research in other fields, mathematics for example, makes its impact more slowly over an extended period of time Impact Factor Years Journal Citation Reports ® – Enhancements

Immunology Journal Citation Reports ® – Enhancements Introduction of a 5-Year Impact Factor : To better gauge the impact of journals within fields where influence of published research evolves over a longer period of time than presented by the traditional 2-Year Impact Factor.  Impact Factor is based on two years of cited journal content – cites in the current year to journal material published in the prior two years.  A 5-Year Impact Factor is based on cites in the current year to journal material published in the prior five years.

Journal Citation Reports ® – Enhancements Geology Introduction of a 5-Year Impact Factor : To better gauge the impact of journals within fields where influence of published research evolves over a longer period of time than presented by the traditional 2-Year Impact Factor. Geology  Impact Factor is based on two years of cited journal content – cites in the current year to journal material published in the prior two years.  A 5-Year Impact Factor is based on cites in the current year to journal material published in the prior five years.

Journal Citation Reports ® – Enhancements Rank in Category table: Many journals maintain an editorial scope that necessitates their inclusion in more than one JCR category. To better reveal the influence of a journal in all assigned categories a Rank in Category table will display each category in which the journal appears along with rank in the category and the Quartile in which the journal is placed in that category - based on Impact Factor.

Journal Citation Reports ® – Enhancements Category Box Plot: A category Box Plot accompanies the Rank in Category table. The spacing between the different parts of the box, the quartiles, helps indicate the degree of dispersion of impact of journals within the category. View the journal's Impact Factor in the context of all Impact Factors for the journal's category as depicted by the graph – envisioning a line at the position of the journal’s Impact Factor helps one to better comprehend the display.

Journal Citation Reports ® – Enhancements  Journal Self-Citation itself is not an inherently “bad” practice.  Authors of course cite related research and this may have been published in the journal to which one in turn submits a paper for publication.  Journals with a very specialized subject focus may naturally display significant rates of self-citation.  However -- 80% of all journals listed in the JCR Science Edition have self-citation rates of less than 20%. Based on trends within a category we can get an idea of what may be excessive self-citation, which weakens the integrity of the journal’s Impact Factor. Journal Self-Citation

Journal Citation Reports ® – Enhancements Illumination of Journal Self-citation Rates: To provide one the ability to easily compare self-citation rates among journals particularly as this influences Impact factor calculations. Category: Materials Science, Composites

Journal Citation Reports ® – Enhancements Eigenfactor Metrics TM : Eigenfactor TM and Article Influence TM : To compliment Impact Factor and other JCR metrics by providing a broader perspective on Journal Influence through specific measures now widely accepted by the scholarly community. These metrics are developed through The Eigenfactor Project™ -- a non- commercial academic research project sponsored by the Bergstrom lab in the Department of Biology at the University of Washington. –

Journal Citation Reports ® – Enhancements Eigenfactor TM Score: Scholarly references join journals together in a vast network of citations. The Eigenfactor Score algorithm uses the structure of the entire network to evaluate the importance of each journal, cutting across all disciplines. Self-citations are excluded. This corresponds to a simple model of research in which readers follow chains of citations as they move from journal to journal. Eigenfactor calculations take into consideration a 5-year span of citation activity utilizing data from the Journal Citation Reports. Journals are considered to be influential if they are cited often by other influential journals.

Journal Citation Reports ® – Enhancements Article Influence TM Score: As with Eigenfactor Score, Article Influence Score: –Uses the structure of the entire citation network to evaluate the importance of each journal, based on JCR data. –Does not consider self-citations The calculation of Article Influence Score does in fact incorporate Eigenfactor Score. However, as Eigenfactor Score can be described as presenting the total collective value provided by all of the articles published in a journal in a year – Article Influence Score measures the average influence of individual articles appearing in the same journal, translating to the importance of an article published in that journal. Because it does present an average for article-level influence, Article Influence is more like the Impact Factor than Eigenfactor Score – though keep in mind the methodology is quite different and therefore provides a perspective different from but complimentary to Impact Factor.

Agenda: Use and Misuse

USING THE IMPACT FACTOR EVALUATING JOURNALS Appropriate use –To evaluate journals Misuse –Evaluation of individual articles –Evaluation of institution or researcher

27 USING THE IMPACT FACTOR MISUSE: EVALUATING INDIVIDUAL PAPERS 30% of articles in Food Policy were not cited at all Source: Thomson Reuters Journal Citation Reports Journal Impact Factor = 2,011

Any questions?