bibliometrics primer

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Bibliometrics : Essential Concepts and Tools Elaine M. Lasda Bergman Bibliographer for Social Welfar and Dewey Reference Dewey Graduate Library

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An introduction to traditional bibliometrics and the use of some newer tools for measuring scholarly influence and impact.


  • 1.Bibliometrics :Essential Concepts and ToolsElaine M. Lasda BergmanBibliographer for Social Welfareand Dewey ReferenceDewey Graduate Library

2. What is bibliometrics?Scholarly communication: tracing the history andevolution of ideas from one scholar to anotherMeasures the scholarly influence ofarticles, journals, scholars 3. The birth of citation analysisEugene Garfield: father of citation analysisdeveloped the first bibliometric index toolsCitation indexes and Journal Citation ReportsISI Indexes: Science Citation Index, Social ScienceCitation Index, Arts and Humanities IndexBetter coverage on hard sciences than on socialsciences and worse still on humanities 4. Garfields metricsCitation countImpact FactorImmediacy IndexCitation Half-Life 5. Citation countNumber of times cited within a given time periodAuthorJournalDoes not take into accountMaterials not included in citation databaseSelf citations 6. Impact factorMeasures impact of a journal (not an article) withina given subjectFormula is a ratio:Number of citations to a journal in a given year fromarticles occurring in the past 2 years Divided by thenumber of scholarly articles published in the journal inthe past 2 years 7. Concerns with impact factorCannot be used to compare cross disciplinary (perGarfield himself) due to different rates of publicationand citationTwo year time frame not adequate for non-scientificdisciplinesCoverage of some disciplines not sufficient in the ISIdatabasesIs a measure of impact a measure of quality? 8. Immediacy indexWhat its supposed to measure: how quickly articles ina given journal have an impact on the disciplineFormula: the average number of times an article in ajournal in a given year was cited in that same year 9. Citation Half-LifeWhat its supposed to measure: duration of relevanceof articles in a given journalFormula: median age of articles cited for a particularjournal in a given year 10. Twenty first century tools 11. Influence of Google Page Rank Eigenvector analysis:The probability that a researcher, in documenting his orher research, goes from a journal to another selecting arandom reference in a research article of the firstjournal. Values obtained after the whole processrepresent a random research walk that starts from arandom journal to end in another after following aninfinite process of selecting random references inresearch articles. A random jump factor is added torepresent the probability that the researcher chooses ajournal by means other than following the references ofresearch articles. (Gonzales-Pereira,, 2010) 12. Sources Using ISI Data 13. Journalranking.comJournal uses ISI data and eigenvector(PageRank) algorhythm to create ones owncategoriesCan assign different weights to citations from the samejournal, the same category and from other categories oronly whithin a specific listNot updated since 2005 14. ISI dataSimilar to PageRankListed in JCR as of 2009Eigenfactor Score : Influence of the citing journal divided by the total number of citations appearing in that journalExample: Neurology (2006): score of .204 = an estimated0.2% of all citation traffic of journals in JCR (Bergstrom &West, 2008).Larger journals will have more citations and therefore willhave larger eigenfactors 15. Article Influence ScoreFrom Eigenfactor: measure of prestige of a journalAverage influence, per article of the papers on ajournalComparable to the Impact FactorCorrects for the issues of journal size in the rawEigenfactor scoreNeurologys 2006 article influence score = 2.01. Orthat an avg. article in Neurology is 2X as influential asan avg. article in all of JCR 16. ScienceWatchProvides quick and dirty articles on hotresearchers, trending research topics, institutions andjournalsMuch on this site (in-cites, etc) are now parts ofanalytical products being sold byThompson; no longerfreeThere are still some good articles, but notsearchable, hit or miss information 17. New sources for citation informationGoogle ScholarScopus 18. Scopus:alternate database of citation dataReview panel, i.e., quality controlBigger field than ISI: covers all the journals in WoS andmoreStrongest in hardsciences, ostensibly improvedsocial science coverage, arts and humanities: aregetting thereAlgorithmically determined with human editing 19. Google Scholaralternate database of citation dataNo rhyme or reason to what is includedBiggest source of citation dataForeign language sourcesSources other than scholarly journalsEntirely algorithmically determined, no human editing 20. Scopus analyticsSNIPSJR/SCIMagoAuthor Evaluator 21. SNIP(Source Normalized Impact Per Paper)Journal Ranking based on citation analysis withadjustments for the frequency of citations of theother journals within the field (the field is all journalsciting this particular journal)SNIP is defined as the ratio of the journals citationcount per paper and the citation potential in itssubject field. (Moed, 2009) 22. SJR:SCImago Journal RankWhat its supposed to measure: current averageprestige per paperSCImago website uses journal/citation data fromScopus, and is also available from scopus dbFormula: citation time window is 3 years instead of 2like JIFCorrections for self citationsStrong correlation to JIF 23. SCImago Journal RankPrestige factors include: number of journals indb, number of papers from journal indatabase, citation numbers and importancereceived from other journals: size dependent: largerjournals have greater prestige valuesNormalized by the number of significant workspublished by the journal: helps correct for sizevariationsCorrections made for journal self citations 24. Scopus Author EvaluatorBreakdown of documents by sourceH-indexCitations per year (graph) 25. Google ScholarPublish or PerishCIDS 26. Publish or PerishProvides a variety of metrics for measuringscholarly impact and output.More useful for metrics on authors than journalsor institutionsUses Google Scholar citation informationUseful for interdisciplinary topics, fields relyingheavily on conference papers or reports, non-English language sources, new journals, etc.Continuously updated since 2006 27. Publish or Perish MetricsBasic metrics:# papers, #citations, active years, years since firstpublished, average #of citations per paper, average # ofcitations per year, average # citations per author, etc.Complex metricsH index (and its many variations, mquotient, g-index (correctsh-index for variations in citation patterns), AR index, AWindexDoes not have any corrections for SELFCITATIONS 28. CIDSMeasures output of authors for prestige andinfluenceSimilar to PoPCorrects for Self-CitationsUses Google Scholar data 29. CIDS metricsCitations per year, h-index, g-index, totalcitations, avg cites per paper, self citations includedand excluded, etc. 30. MesurMetric based on usage, citation and bibliographicdataUses its own datbases ofdocuments/metadata/reference, users &authors, usage events and citationsProject seems to be dead? 31. ConsiderationsDont measure an individual journals impact by themetrics for the entire journalCluster of years of citationsNegative citationsA few high impact citations or a lot of low impactciationsSource of citing documentsForeign, conference proceedings, traditional