The document discusses various quality indices used to evaluate research publications and authors. It defines indices such as the impact factor, immediacy index, Eigenfactor, SCImago Journal Rank, H-index, G-index, and HB-index. It provides details on how each index is calculated and its significance. It also discusses limitations of impact factor and compares different journal quality indices. The document aims to explain these quality metrics to evaluate journals and authors.
Navigating the Misinformation Minefield: The Role of Higher Education in the ...
Quality Indices
1. Dr. Chetan B. Bhatt
Professor and Head,
Vishwakarma Government Engineering College,
Chandkheda, Ahmedabad
Quality Indices
2. 2
Unit-IV: Research Publication & Presentation:
Thesis, Research paper, Review Article & Technical
Reports: Organization of thesis and reports,
formatting issues,
citation methods, references,
effective oral presentation of research.
Quality indices of research
publication: impact factor, immediacy
factor, H- index and other citation
indices.
5. Historical note
5
There are three factors that led to development of
citation indexing back in 1950’s –
1. Followed by World War – II, there were huge
influx of government fund for research. Publication
of research finding by researchers burgeon the
body of knowledge. In order to retrieve huge
document database it became necessary to index
it. Manual indexing practice is time consuming
and not a cost effective one.
2. Then the current method of subject indexing was
not useful because of discipline specific
terminology etc.
3. Availability of machine for computation and data
processing.
6. Historical development
6
The Impact Factor was developed by Eugene
Garfield, the founder of the Institute for Scientific
Information (presently a part of Thomson
Reuters), in 1955 following ideas inspired by
Vannevar Bush's famous article "As We May
Think" in 1945 . (available at
http://adammikeal.com/courses/chi/files/jan26.bus
h.pdf)
The original article "Citation indexes for science:
a new dimension in documentation through
association of ideas" by Garfield was published in
Science 1955;122:108-111
(available at
http://www.garfield.library.upenn.edu/papers/news
7. Why?
7
Evaluate the scholarly worth of a journal
Rank journals within a discipline
Help you decide where to publish your article for
maximum impact
Evaluation for promotion / tenure / grants, or in
some countries, even government funding of an
institution.
Frequently used as an evaluation source by
librarians during journal cancellations or new
purchases
8. Why?
8
Below are some examples* –
In England, hiring panels routinely consider impact
factors
By Spanish law, researchers are rewarded for
publishing in journals defined by ISI as prestigious
(upper third of impact factor listings)
In China, scientists get cash bonuses for publishing
in high-impact journals. In some schools, physics
students must publish at least 2 articles with a
combined Impact Factor of 4 to get their PhD
* From the Chronicle of Higher Education (2005) “The
Number that is Devouring Science”
10. Journal Quality Indices
10
Following are quality indices commonly used
for journals
Thomson Reuters (Web of Science)
Impact Factor
Immediacy Index
EigenFactor
Scopus (Elsevier)
SCImago Journal Rank (SJR)
11. Impact Factor (IF)
11
The impact factor is a measure reflecting the
average number of citations to articles published
in science and social science journals.
It is frequently used as a proxy for the relative
importance of a journal within its field, with
journals with higher impact factors deemed to be
more important than those with lower ones.
The impact factor was devised by Eugene
Garfield, the founder of the Institute for
Scientific Information (ISI), now part of
Thomson Reuters. Impact factors are calculated
yearly for those journals that are indexed in
Thomson Reuters Journal Citation Reports.
12. Web of Science
12
Thomson Reuters (formerly ISI) has one,
huge database, Web of Science, that…
Indexes selected journals
> 8,000 science; > 3,000 social science
journals;
> 1,800 Arts & Humanities
Tracks “cited references” and “times cited”
13. Where do we find Impact Factors?
13
Impact factors are listed in Journal Citation
Reports JCR)
You can easily get to the JCR from the Web of
Science.
Check ISI Web of Knowledge with a new
session if necessary at
http://www.webofknowledge.com/ to get the up-
to-date impact factor scores of 20010/2011
journal ranking performance. (Requires
Subscription)
Both the Web of Science and the JCR are
based on the same database of journal citations
and cited references. Use Web of Science for
14. Journal Citation Report
14
Journal Citation Reports (JCR) is an annual
publication by the Healthcare & Science division
of Thomson Reuters. It has been integrated with
the Web of Knowledge, by Thomson Reuters,
and is accessed from the Web of Science to JCR
Web.
It provides information about academic journals in
the sciences and social sciences, including
impact factors. It was originally published as a
part of Science Citation Index, and is compiled
from the citation data found there.
Journal Citation Report (Example)
16. Calculation of Impact Factor
16
In a given year, the impact factor of a journal is the
average number of citations received per paper
published in that journal during the two preceding
years.
Calculation
A = the number of times articles published in 2009 and
2010 were cited by indexed journals during 2011.
B = the total number of "citable items" published by that
journal in 2009 and 2010. ("Citable items" are usually
articles, reviews, proceedings, or notes; not editorials or
Letters-to-the-Editor.)
2011 impact factor = A/B.
(Note that 2011 impact factors are actually published in
2012; they cannot be calculated until all of the 2011
publications have been processed by the indexing
agency.)
17. Criticism of Impact Factor
17
Only a limited subset of journals is indexed by ISI
Only uses the articles cited by the ~13,000 “ISI
journals”
Some disciplines are especially poorly covered
Biased toward English-language journals
ISI has recently added several hundred non-English
journals
Short (two year) snapshot of journal
Some disciplines use older material more or take
time to cite new research
JCR now also includes the 5-year data
Is an average; not all articles are equally well-cited
18. Criticism of Impact Factor
18
Includes self-citations, that is articles in which the
article cites other papers in the same journal
Only includes “citable” articles in the denominator of
the equation, i.e., articles and reviews
Editors may skew IF by increasing the number of
review articles, which bring in more citations
(increases the numerator)
Or by increasing the number of “news” items (e.g.,
Science, general medical journals) , which are cited
(appear in numerator) but not considered “citable”
(and so aren’t in the denominator)
It is expensive to subscribe to the JCR
19. Immediacy Index
19
An immediacy index is a measure of how topical
and urgent work published in a scientific journal
is.
Along with the better known impact factor
measure, it is a calculated each year by the
Institute for Scientific Information (ISI) for
those journals which it indexes; both impact
factors and immediacy indices are published
annually in the Journal Citation Reports.
20. Calculation
20
The immediacy index is calculated based on the
papers published in a journal in a single calendar
year. For example, the 2005 immediacy index for
a journal would be calculated as follows:
A = the number of times articles published in 2005
were cited in indexed journals during 2005
B = the number of articles, reviews, proceedings or
notes published in 2005
2005 immediacy index = A/B
As with the impact factor, There are some nuances
to this: ISI excludes certain article types (such as
news items, correspondence, and errata) from the
denominator.
21. EigenFactor
21
The Eigenfactor Project is a non-commercial
academic research project sponsored by the
Bergstrom lab in the Department of Biology at the
University of Washington.
Available free at eigenfactor.org (1995-2009
data)
As with the JCR, only ISI journals are ranked
Uses “all” ISI data, analyzed differently.
all cited and citing references (so includes
citations from non-ISI journals, books,
dissertations, etc.)
22. Calculation of Eigenfactor
22
Uses similar algorithm as Google’s PageRank
By this approach, journals are considered to be
influential if they are cited often by other
influential journals.
Looks at five years of data
Calculation method
23. Comments on Eigenfactor score
23
Eigenfactor Score: … the higher the better
For a journal, the number of times articles published
in the previous five years have been cited in the
current year. It also considers which journals have
contributed these citations so that highly cited
journals will influence the score more than lesser
cited journals (similar to the Google pagerank
algorithim). Self citations are removed.
A measure of the journal’s total importance to the
scientific community.
Eigenfactor scores are scaled so that the sum of the
Eigenfactor scores of all journals listed in
Thomson’s Journal Citation Reports (JCR) is 100.
24. Article Influence
24
The Article Influence score measures the average
influence, per article, of the papers in a journal.
As such, it is comparable to Thomson Scientific's
Impact Factor.
It is calculated by dividing the Eigenfactor score
by the number of articles published. Article
Influence scores are normalized so that the mean
article in the entire Thomson Journal Citation
Reports (JCR) database has an article influence
of 1.00.
The Article Influence scores for journals are
available at http://www.eigenfactor.org/
25. Comments on Article Influence
25
Article Influence Score: … the higher the
better
The average influence, per article, of the papers
in a journal. As such, it is comparable to the
Journal Impact Factor.
Article Influence scores are normalized so that
the mean article in the entire Thomson Journal
Citation Reports (JCR) database has an article
influence of 1.00. A score greater than 1.00
indicates that each article in the journal has
above-average influence.
Still, as with IFs, it’s best to “compare” within
subjects.
26. Where to look for EF and AI?
26
Let us we look at EF and AI for control journals
Open http://eigenfactor.org
Choose ISI journals
Select automation and control category
It will display the list of journals with EF and AI,
e.g. as given
(Automation and control)
27. SCImago Journal Rank (SJR)
27
Developed by Professors Félix de Moya,
SCImago Journal Rank (SJR) is a prestige metric
based on the idea that ‘all citations are not
created equal’.
With SJR, the subject field, quality and reputation
of the journal have a direct effect on the value of
a citation.
SJR is a measure of scientific influence of
scholarly journals that accounts for both the
number of citations received by a journal and the
importance or prestige of the journals where such
citations come from.
28. SCImago Journal Rank (SJR)
28
The citation PageRank of a journal calculated on
the basis of the Scopus citation data divided by
the number of articles published by the journal
over 3 years.
Similar to Eigenfactor methods, but based on
citations in Scopus instead of Web of Science.
Freely available at scimagojr.com
Covers more journals (~20,000) than JCR
because Scopus covers more journals than
Web of Science
More international diversity
3 years of citations; no self-citations
29. SCImago Journal Rank (SJR) Algorithm
29
The SJR indicator, which is inspired by the
PageRank algorithm, was developed for
extremely large and heterogeneous journal
citation networks. It is a size-independent
indicator and it ranks journals by their ‘average
prestige per article’ and can be used for journal
comparisons in science evaluation processes.
http://www.scimagojr.com/index.php
30. Scimago other ranking
30
The Scimago also rank institute, and country
for scientific research work.
Download this free report (2011) at:
www.scimagoir.com/
Ranks 3,042 institutions, worldwide
Provides 5 indicators of research performance,
stressing research output, citations, international
collaboration and impact.
Data comes from the Scopus db (analyzed 18,750
research publications, mostly journals and
proceedings)
Data is from 2005-2009
33. H - index
33
Proposed by JE Hirsch as an index to quantify an
individual's scientific research output
Remember, Impact Factor is just for journals,
though it’s often used to evaluate authors.
Combines an assessment of both quantity
(number of papers) and quality (impact, or
citations to these papers).
The index can also be applied to the productivity
and impact of a group of scientists, such as a
department or university or country.
34. 34
The index is based on the distribution of citations
received by a given researcher's publications.
Hirsch writes:
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.
In other words, a scholar with an index of h has
published h papers each of which has been cited
in other papers at least h times
35. Calculating H - index
35
h-index is automatically calculated:
Web of Science
Scopus
Publish or Perish (free download), based on
data in Google Scholar
h-index can also be manually calculated for an
author based on the number of papers authored
and the number of times each paper has been
cited.
42. G - index
42
The g-index is an index for quantifying scientific
productivity based on publication record. It was
suggested in 2006 by Leo Egghe.
The index is calculated based on the distribution of
citations received by a given researcher's
publications:
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.
In simple terms, this means that an author that produces
n articles is expected to have, on average, n citations for
each of them, in order to have a g-index of n. In this way,
it is similar to the h-index, with the difference that the
number of citations per article is not explicit.
43. H-b index
43
The h-b-index is an extension of the h-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.
44. H-b index
44
The h-index defined by J. Hirsch is:
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.
Online web programs are available to directly calculate a
scientist's M-number and H-index values, such as
ScHolarIndex
(http://interaction.lille.inria.fr/~roussel/projects/scholarind
ex/index.cgi) and Publish and Perish.[2]
46. Basic Journal Information
46
The information given for each journal includes:
The basic bibliographic information of publisher, title
abbreviation, language, International Standard
Serial Number (ISSN)
The subject categories (there are 171 such
categories in the sciences and 54 in the social
sciences)