G index, contemporary h index, factors in age of articles, individual h index: per author, hm index, corrects for multiple authors by reducing paper counts,
Transcript of "Bibliometrics Primer"
Bibliometrics :Essential Concepts and Tools Elaine M. Lasda Bergman Bibliographer for Social Welfare and Dewey Reference Dewey Graduate Library
What is bibliometrics?Scholarly communication: tracing the history andevolution of ideas from one scholar to anotherMeasures the scholarly influence ofarticles, journals, scholars
The birth of citation analysisEugene Garfield: “father of citation analysis”developed the first bibliometric index toolsCitation indexes and Journal Citation Reports “ISI Indexes”: Science Citation Index, Social Science Citation Index, Arts and Humanities IndexBetter coverage on hard sciences than on socialsciences and worse still on humanities
Citation countNumber of times cited within a given time period Author JournalDoes not take into account Materials not included in citation database Self citations
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 from articles occurring in the past 2 years Divided by the number of scholarly articles published in the journal in the past 2 years
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”?
Immediacy indexWhat it’s 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
Citation Half-LifeWhat it’s supposed to measure: duration of relevanceof articles in a given journalFormula: median age of articles cited for a particularjournal in a given year
Influence of Google Page Rank Eigenvector analysis: “The probability that a researcher, in documenting his or her research, goes from a journal to another selecting a random reference in a research article of the first journal. Values obtained after the whole process represent a ‘random research walk’ that starts from a random journal to end in another after following an infinite process of selecting random references in research articles. A random jump factor is added to represent the probability that the researcher chooses a journal by means other than following the references of research articles.” (Gonzales-Pereira, et.al., 2010)
Journalranking.comJournal Ranking.com uses ISI data and eigenvector(PageRank) algorhythm to create one’s owncategories Can assign different weights to citations from the same journal, the same category and from other categories or only whithin a specific list Not updated since 2005 http://libguides.library.albany.edu/content.php?pid=600 86&sid=441804
Eigenfactor.org http://libguides.library.albany.edu/content.php?pid=60086&sid=441804 Uses ISI data Similar to PageRank Listed in JCR as of 2009 Eigenfactor Score : Influence of the citing journal divided by the total number of citations appearing in that journal Example: Neurology (2006): score of .204 = an estimated 0.2% of all citation traffic of journals in JCR (Bergstrom & West, 2008). Larger journals will have more citations and therefore will have larger eigenfactors
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 scoreNeurology’s 2006 article influence score = 2.01. Orthat an avg. article in Neurology is 2X as influential asan avg. article in all of JCR
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 informationhttp://sciencewatch.com/dr/sci/11/
New sources for citation information Google Scholar Scopus
Scopus:alternate database of citation dataReview panel, i.e., quality controlBigger field than ISI: covers all the journals in WoS andmoreStrongest in “hard”sciences”, ostensibly improvedsocial science coverage, arts and humanities: are“getting there”Algorithmically determined with human editing
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
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 journal’s citationcount per paper and the citation potential in itssubject field. (Moed, 2009)http://www.scopus.com/home.url
SJR:SCImago Journal RankWhat it’s supposed to measure: “current “averageprestige per paper”SCImago 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
SCImago Journal RankPrestige factors include: number of journals indb, number of papers from journal indatabase, citation numbers and “importance”received 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
Scopus Author EvaluatorBreakdown of documents by sourceH-indexCitations per year (graph)
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
Publish or Perish MetricsBasic metrics: # papers, #citations, active years, years since first published, average #of citations per paper, average # of citations per year, average # citations per author, etc.Complex metrics H index (and its many variations, mquotient, g-index (corrects h-index for variations in citation patterns), AR index, AW indexDoes not have any corrections for SELFCITATIONS
CIDSMeasures output of authors for prestige andinfluenceSimilar to PoPCorrects for Self-CitationsUses Google Scholar data
CIDS metricsCitations per year, h-index, g-index, totalcitations, avg cites per paper, self citations includedand excluded, etc.http://cids.di.fc.ul.pt/cids_3_0/info.php?acc=25201514041114103161
MesurMetric based on usage, citation and bibliographicdataUses its own datbases ofdocuments/metadata/reference, users &authors, “usage events” and citationsProject seems to be dead?
ConsiderationsDon’t measure an individual journal’s impact by themetrics for the entire journalCluster of years of citationsNegative citationsA few high impact citations or a lot of low impactciationsSource of citing documents Foreign, conference proceedings, traditional
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