?????? ?????? ?? ????? ? ???????? ????????: H-Index ? ?????? ??

1
?????? ?????? ?? ????? ? ???????? ????????
H-Index ? ?????? ??

• ?????? ?????????
• ?????? ??????? ? ??????? ????? ??????? ????? ?
  ????? ?????? ?? ?????? ??????? ???? ????? ?????

2
?????? ?? ????? ? ???????? ???????? H-Index ?
?????? ??

• Payam Kabiri, MD. PhD.
• Epidemiologist
• Tehran IsfahanUniversities of Medical Sciences

3
?????? ????? !

• ?????????? ? ????????? ?????? ? ??????
• ????? ????? ???????? ????????
• ?????? ?? ?????????????? ???????
• ????? ???? H-Index
• ????? ? ????? H-Index
• ??????? ?????? H-Index
• ??? ????

4
Scientometrics (bibliometrics)

• Scientometrics (bibliometrics) - The measurement
  of scientific output activity through statistics
  on academic publications
• The scope of bibliometrics includes
• all quantitative aspects and models of science
  communication, storage, dissemination and
  retrieval of scientific information.

5
????? ????????

• ?? ???? ?? ??????? ???? ?? ?? ?? ????? ??? ??????
  ?? ?????? ???????? ????? ????? ??? ????
  ????????.
• ??? ???? ?? ?????? ???? ?? ????? ??? ?? ????
  ?????????? ???.

6
Scientometrics
informetrics
bibliometrics
scientometrics
cybermetrics
webometrics
7
Bibliometric data used for..

• Scientific output evaluation
• Impact
• Citations
• History of science
• Publication strategies
• Science policy resource allocation
• Collection management
• Sociology of science
• Information organization
• Information management utilization

8
Links of bibliometrics with related research
fields and application services
Science policy
Scientific information
Research management
Librarianship
Services for
Research in
Economics
Sociology of science
History of science
Library and Information Science
Life sciences
Informetrics
Mathematics/Physics
Webometrics
9
Why do we evaluate scientific output
International

• Grant Allocations
• Policy Decisions
• Benchmarking
• Promotion
• Collection management
• Funding allocations
• Research

National
Institutional
Faculty
SPLIT IN NEEDS
SPLIT IN NEEDS
Researchers
10
Scientists Ranking Methods

• Evaluation of scientists by experts
• e.g., surveys
• Citation Analysis
• Task Compute a score for the objects
• Hybrid method of previous two

11
3 Kinds of Citation Data Indexes

• Articles
• Citation Impact
• Authors
• Number of papers (Quantity)
• Number of Citations (Quality)
• Average number of citations/article
• h-index g-index (Quantity Quality Both)
• Journals
• Journal Impact Factor
• h-index

12
(No Transcript)
13
A Sample of a Sceintometery Report
14
3 Kinds of Citation Data

• Articles
• Citation Impact
• Authors
• Number of papers (Quantity)
• Number of Citations (Quality)
• Average number of citations/article
• h-index g-index Quantity Quality Both)
• Journals
• Journal Impact Factor
• h-index

15
ISI Impact Factor
A total cites in 1992 B 1992 cites to articles
published in 1990-91 (this is a subset of A) C
number of articles published in 1990-91D B/C
1992 impact factor
16
Citation Databases

• Web of Science
• Scopus
• Google Scholar

17
Other Tools Available

• Other bibliometric indicators
• Journal Citation Reports (JCR)
• Other indicators databases (national, essential,
  university, institutional)
• ISIHighlyCited.com

18
WoS and Scopus Subject Coverage ( of total
records)
WoS SCOPUS
Google Scholar ?
19
Web of Science

• Covers around 9,000 journal titles and 200 book
  series divided between SCI, SSCI and AHCI.
• Electronic back files available to 1900 for SCI
  and mid- 50s for SSCI and mid-70s for AHCI.
• Very good coverage of sciences patchy on
  softer sciences, social sciences and arts and
  humanities.
• US and English-language biased.
• Full coverage of citations.
• Name disambiguation tool.
• Limited downloading options.

20
Scopus

• Positioning itself as an alternative to ISI
• More journals from smaller publishers and open
  access (15,000 journals 750 conf proceedings)
• Source data back to 1960.
• Excellent for physical and biological sciences
  poor for social sciences does not cover
  humanities or arts.
• Better international coverage (60 of titles are
  non-US)
• Back to 1996 ! (e.g. citation data for the last
  decade only)
• Not cover to cover and not up to date
• Easy to use in searching for source publications
  clumsy in searching cited publications.
• Citation tracker works up to 1000 records only.
• Limited downloading options.

21
Google Scholar

• Better coverage for all citations as it retrieve
  web !
• More coverage of references also gray literature
  !
• Coverage and scope?
• Inclusion criteria?
• Very limited search options
• No separate cited author search
• Back to 1990 NOT more !
• Free!

22
What is Scopus Database?

• ????? ???? ????????   (Scopus (Database
• ???? ???????? ??? ?? 15200 ????? ????
• ?????????? ??? ?? 30 ?????? ????? ????? ?? 4000
  ???? ???? ??????????
• ?????????? ??? ?? 265 ?????? Citation
• ?????????? ????? ????? ????? ??? ?? ??????

23
What is Scopus?

• 15,200 titles from more than 4,000 publishers
• 1,000 Open Access journals
• 500 Conference Proceedings
• 400M web pages
• 21M patents
• Repositories
• Digital Archives

24
Content Update

• 30 million records, of which
• 15 million records include references going back
  to 1996
• 15 million pre-1996 records go back as far as
  1900
• 265 million references, added to records from
  1996 onwards
• In addition to traditional scientific and
  academic journals, Scopus covers
• 1000 Open Access journals
• 500 Conference Proceedings
• 600 Trade Publications
• 125 Book Series
• Medline (100 coverage)
• 275 million quality web sites including 21
  million patents from 5 patent offices
• UK Patents added to Scirus

25
What is Scopus?
240 million scholarly Web items, E-prints,
theses, dissertations, 13 M patents

• 15 Elsevier sources
• 85 other publishers

Fastest route to FullText
26
Valuable archive included
1966
Abstract30 million 1.1 million per year Cited
References 265 million 10 years 25 million each
year Currency Updated daily
1996
2006
15,100 current journal sources
27
Scopus Coverage15,100 Unique titles
Life Health (100 Medline)
Chemistry Physics Engineering
Biological Agricultural Environmental
Social Sciences Psychology Economics
28
International distribution of titles
806
29
Geographical spread of Scopus content
30
Iranian Titles indexed in Scopus
















Iranian Biomedical Journal
Archives of Iranian Medicine
Daru
Iranian Journal of Diabetes and Lipid Disorders
Iranian Journal of Medical Sciences
Iranian Journal of Public Health
Journal of Medicinal Plants
Yakhteh

31
Bibliometric Tool Development of Scopus
IMPLEMENT
Launch Scopus

• Citation Tracker
• Author Identifier
• WebCites
• PatentCites

• h-index
• Custom Data
• End 2007 release

2006
2007
2005
2004
STRATEGY
32
Difficulties of Old Criteria

• Total number of papers (Quantity)
• Total number of citations (Quality)
• Average number of citations/article (Deepened on
  the outliers)
• Journal Impact Factor (Discipline based,
  dependent on the outliers)

33
H-index was born !

• We need an Index both to include quantity also
  quality of an authors' paper
• Productivity
• Impact
• Not affected by big hits
• Not affected by noise

34
The h-index

• Hirsch, J. E. (2005). An index to quantify an
  individual's scientific research output.
  Proceedings of the National Academy of Sciences
  of the United States of America, 102(46),
  16569-16572.
• Meaningful when compared to others within the
  same discipline area. Researchers in one field
  may have very different h-indices than
  researchers in another (e.g. Life Sciences vs.
  Physics).

35
The h-index

• Hirsch, J.E. "an index to quantify an
  individual's scientific research output".
  Proceedings of the National Academy of Sciences
  of the United States of America (PNAS). 102(46),
  16569-16572
• Available at http//arxiv.org/pdf/physics/0508025

36
The H-index a definition

• The H-index is the highest number of papers a
  scientist has that have at least that number of
  citations. Nature (2005)

37
What is the h-Index?

• Performance measurement tool for scientific
  authors (similar idea to journal impact factors
  but for individuals)Established by Jorge Hirsch
  at UC San Diego
• A scientist has index h if h of his/her Np
  papers have at least h citations each, and the
  other (Np- h) papers have no more than h
  citations each.
• Source Hirsch, J. E. (2005, September 29). An
  index to quantify an individuals scientific
  research output. Retrieved from
  http//arxiv.org/abs/physics/0508025

38
The h-index

• DefinitionA researcher has h-index h if
• h of his Np articles have received at least h
  citations each
• the rest Np-h articles have received no more than
  h citations each

39
H-index Concept through its Graph
40
The h - Graph
41
The h-index

• ???? ????? ?? ???????? ???????? ???. ??? ???? ??
  ??? 2005 ?????? ???? Jorge Hirsch ?? ???????
  ????????? ????? ??. ??? ???? ?? ???? ?? ???
  ??????? ???? ??? ? ??????? ??? ???????? ??????
  ?????? ????? ??? ???.

42
The h-index

• ????? H-Index ????? ??? ?? ????? ?????? ???????
  ?? ????? ??????? ????? ?? h ? ?? ???? ?? ??
  ?????. ???? ??????? H-Index ????? 5 ????? ?????
  ?? ??? ??? ?? ??? ???? 5 ????? ????? ??? ???? ??
  ?????? ????? 5 ?????? ?? Citation ?????. ??
  ????? ???? ????? ?? ??? ??? ?? ???? ?????? ???
  ???? ???? ?? 5 ?????? ?????.
• ?????? ??? ???? ????? Impact Factor ???? ??????
  ????? ??????.

43
The highest h-index in the World Iran

• ???????? ???? h ?? ???? ????? ?? ???? ???? ?????
  ????? ?? 197 ? ???????? ???? h ?????? ????? ????
  ???? ???? ???? ??? ????? ???? ??????? ????
  ???????? ?? ??? h ????? 33 ?? ????.

44
Terminology

• Np total number of papers
• Nc,tot total number of citations
• Y(now) present year
• Y(i) year of publication of paper i
• C(i) set of citations to paper i

45
The h-index

• A scientist has index h if h of his or
  her Np papers have at least h citations each
  and the other ( Np h ) have at least h
  citations each

Doc 1 2 3 4 5 6 7 8 9 10 11
Cit 49 23 15 14 6 3 1 1 0 0 0
46
H-index example

• Author A
• Author B

Doc 1 2 3 4 5 6 7 8 9
Cit 55 45 20 10 5 4 3 2 1
Doc 1 2 3 4
Cit 25 20 9 6
47
H-index example

• Author X has 5 published articles
• Article1, citations 5
• Article2, citations 10
• Article3, citations 100
• Article4, citations 6
• Article5, citations 4
• The H-index of X is 4 there are 4 papers with at
  least 4 citations each.

48
The h-index

• It could be used for an specific Author
• Evaluate the Research Performance of Author
• Or could be used for a group of Papers of an
  institution, department or journal which
• Evaluate the Impact of the group of special papers

49
H-index drawbacks

• Like impact factors depends on subject area
• It is a growing function over time
• It does NOT show the current activity or
  inactivity of the author
• Disadvantages younger researchers (without
  previous track record)
• Scientists with short scientific life are out of
  competition

50
The Contemporary h-index

• The Contemporary h-index was proposed by Antonis
  Sidiropoulos, Dimitrios Katsaros, and Yannis
  Manolopoulos
• It adds an age-related weighting to each cited
  article, giving less weight to older articles.

51
The g-index

• The g-index was proposed by Leo Egghe It is
  defined as follows
• Given a set of articles ranked in decreasing
  order of the number of citations that they
  received, the g-index is the (unique) largest
  number such that the top g articles received
  (together) at least g2 citations.
• It aims to improve on the h-index by giving more
  weight to highly-cited articles.

52
The g-index

• Suggested in 2006 by Leo Egghe.
• The index is calculated based on the distribution
  of citations received by a given researcher's
  publications.

53
The g-index

• Given a set of articles ranked in decreasing
  order of the number of citations that they
  received, the g-index is the (unique) largest
  number such that the top g articles received
  (together) at least g2 citations
• This index is very similar to the h-index, and
  attempts to address its shortcomings.

54
The h-b-index

• The h-b-index developed by Michael Banks of the
  Max Planck Institute for Solid State Research in
  Germany, takes the index further by evaluating
  the impact of compounds used in solid-state
  physics and scientific topics in general.
• The h-b-index is defined in the same manner as
  the h-index, but is based on a topic (or
  compound) search instead of a scientists name.

55
The h-b-index

• A scientist has index h if h of his/her Np papers
  have at least h citations each, and the other (Np
  h) papers have at most h citations each.
• For the case of a topic it is useful to define
  the h-b index in terms of the number of years, n
  as h nm
• If the h-b index is linear with the number of
  years, then m is given as the gradient. In this
  respect, a compound or topic with a large m and
  h-b index can be defined as a hot topic.

56
The H-Graphs in Scopus

• A more comprehensive way evaluating an author
• Using Author Search, Scopus give us three
  different graphs
• H-Index Graph of given Author
• No of Author Papers (Articles) per year
• No of Author Citations per year

57
No of articles
No of citations
h-index plot
58
The h-index

• Plots citations per article
• Incision h-index
• Shows low highly cited-by counts
• Completely transparent
• The date range can change

Practical Interpretation Promotion, Evaluation,
Funding, Tenure, Benchmarking
59
Author articles history

• Shows level of activity
• Shows peaks and troths in publication history
• Can change the date range

Practical Interpretation Promotion, Evaluation,
Funding, Tenure, Benchmarking
60
Author Cited-bys

• Shows level of activity
• Shows highs lows
• Can change the date range
• Time lag!

Practical Interpretation Promotion, Evaluation,
Funding, Tenure, Benchmarking
61
How to calculate h-index through Scopus

• There is two way to calculate it according to the
  way you want
• If you want it for an Author
• Search the Author, It will calculate it
  Automatically for you.
• If you want it for a group of Papers
• Search them then use the track citation sort
  them out to count calculate it Manually.

62
The Hirsch IndexFor a Group of Papers

• Run an author search
• Sort result by citations, clicking on Cited by
• Scroll down the new display of results until the
  ranking number is equal or less than the number
  of citations.
• That ranking number is the Hirsch Index for that
  author.

63
Author Identifier functionality

• Author Identifier enables Scopus users to avoid
  two major problems which affect most AI
  databases
• How to distinguish between an authors articles
  and those of another author sharing the same
  name?
• How to group an authors articles together when
  his or her name has been recorded in different
  ways?
• With other databases, these problems can result
  in retrieving incomplete or inaccurate results.

64
Calculating the H-indexFor a Group of Papers
65
Indicators of quality as measured using published
outputs

• Number of publications
• Citation counts to these publications (adjusted
  for self-citations) -what window should be
  used? 4, 5, 10 years?
• Citations per publication
• Percentage of uncited papers
• Impact factors (of publishing journals)
• Diffusion factor (of citing journals) profile
  of users of research (who, where, when and what)
• Impact factor of a scholar - Hirsh index (h
  index)
• (numbers of papers with this number of
  citations).
• Your h index 75 if you wrote at least 75 papers
  with 75 citations each.
• Note These should not be seen as absolute
  numbers but always seen in the context of the
  discipline, research type, institution profile,
  seniority of a researcher, etc.

66
Calculating h-index using Thomson ISI Web of
Science

1. Conduct a General Search
2. Automatic click on Citation Report, or,
3. Manual sort by Times Cited

67
Calculating h-index using Google Scholar

• There are different ways to do it also
  different interfaces
• 1- Publish or Perish Interface
• You can download it here.
• 2- Another Script, Click here.
• 3- Also this one.

68
Compare like with like!

• Applied research attracts fewer citations than
  basic research.
• Differences in citation behaviour between
  disciplines (e.g. papers in organisational
  behaviour attract 5 times as many citations as
  papers in accounting).
• Highest IF journal in immunology is Ann Rev Immun
  (IF 47.3) Mean for cat. 4.02 and in health care
  and services category is Milbank Q. (IF of 3.8).
  Mean for cat. 1.09.
• Matthew effect.
• Benchmarking must be done using comparable
  variables!
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

69
Harzings Publish or Perish

• A software program that retrieves and analyzes
  academic citations. It uses Google Scholar to
  obtain the raw citations, then analyzes these and
  calculates a series of citation metrics.

70
H-Index Advantages

• The h-index was intended to address the main
  disadvantages of other bibliometric indicators,
  such as total number of papers or total number of
  citations.
• It simultaneously measure the quality and
  sustainability of scientific output, as well as,
  to some extent, the diversity of scientific
  research.

71
H-Index Advantages

• The h-index is much less affected by
  methodological papers proposing successful new
  techniques, methods or approximations, which can
  be extremely highly cited. For example, one of
  the most cited condensed matter theorists, John
  P. Perdew, has been very successful in devising
  new approximations within the widely used density
  functional theory. He has published 3 papers
  cited more than 5000 times and 2 cited more than
  4000 times. Several thousand papers utilizing the
  density functional theory are published every
  year, most of them citing at least one paper of
  J.P. Perdew. His total citation index is close to
  39 000, while his h-index is large, 51, but not
  unique. In contrast, the condensed-matter
  theorist with the highest h-index (94), Marvin L.
  Cohen, has a lower citation index of 35 000. One
  can argue that in this case the h-index reflects
  the broader impact of Cohen's paper in
  solid-state physics due to his larger number of
  highly-cited papers.

72
H-Index Problems

• The h-index is bounded by the total number of
  publications. This means that scientists with a
  short career are at an inherent disadvantage,
  regardless of the importance of their
  discoveries. For example, Évariste Galois'
  h-index is 2, and will remain so forever. Had
  Albert Einstein died in early 1906, his h-index
  would be stuck at 4 or 5, despite his being
  widely acknowledged as one of the most important
  physicists, even considering only his
  publications to that date.
• The h-index does not consider the context of
  citations. For example, citations in a paper are
  often made simply to flesh-out an introduction,
  otherwise having no other significance to the
  work. h also does not resolve other contextual
  instances citations made in a negative context
  and citations made to fraudulent or retracted
  work. (This is true for other metrics using
  citations, not just for the h-index.)
• The h-index does not account for confounding
  factors. These include the practice of
  "gratuitous authorship", which is still common in
  some research cultures, the so-called Matthew
  effect, and the favorable citation bias
  associated with review articles.

73
H-Index Problems

• The h-index has been found to have slightly less
  predictive accuracy and precision than the
  simpler measure of mean citations per paper.
• While the h-index de-emphasizes singular
  successful publications in favor of sustained
  productivity, it may do so too strongly. Two
  scientists may have the same h-index, say, h
  30, but one has 20 papers that have been cited
  more than 1000 times and the other has none.
  Clearly scientific output of the former is more
  valuable.

74
H-Index Problems

• The h-index is affected by limitations in
  citation data bases. Some automated searching
  processes find citations to papers going back
  many years, while others find only recent papers
  or citations. This issue is less important for
  those whose publication record started after
  automated indexing began around 1990. Citation
  data bases contain some citations that are not
  quite correct and therefore will not properly
  match to the correct paper or author.
• The h-index does not account for the number of
  authors of a paper. If the impact of a paper is
  the number of citations it receives, it might be
  logical to divide that impact by the number of
  authors involved. (Some authors will have
  contributed more than others, but in the absence
  of information on contributions, the simplest
  assumption is to divide credit equally.) Not
  taking into account the number of authors could
  allow gaming the h-index and other similar
  indices for example, two equally capable
  researchers could agree to share authorship on
  all their papers, thus increasing each of their
  h-indices. Even in the absence of such explicit
  gaming, the h-index and similar indices tend to
  favor fields with larger groups, e.g.
  experimental over theoretical.

75
(No Transcript)
76
????? ! Email ??? ??? ??????

• payam.kabiri_at_gmail.com