The document discusses the impact factor (IF), which is a measure of the citations received by a journal's articles over a two-year period. A journal's impact factor is calculated by dividing the number of citations received in the current year by documents published in the previous two years. Higher impact factors indicate a journal is more important or influential within its field. While impact factors are commonly used to compare journals, their use is controversial as they may inaccurately reflect the quality of individual articles and influence researcher behavior.

1. The Impact Factor of Journals

2. Impact Factor (IF)
 The impact factor (IF) is a measure of the average number of
citations to articles published in journals, books, patent document,
thesis, project reports, newspapers, conference/seminar
proceedings, documents published in internet, notes and any
other approved documents.
 It is frequently used as an indirect means for the relative
importance of a journal within its field
 Higher impact factors are often 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.

3. Journal Impact Factor (JIF)
 Journal Impact Factor (JIF) of a journal is a measure reflecting the
yearly average number of citations to recent articles published in
that journal.
 It is measure of the relative importance of a journal within its field,
with journals of higher journal impact factors judged to be more
important than those with lower ones.
 JIf are calculated in Yearly/Half-yearly/Quarterly/Monthly for
those journals that are indexed in Journal Reference Reports (JRR).
 Impact factors are calculated yearly starting from 1975 for those
journals that are listed in the Journal Citation Reports.

4. Method of Calculation
 The journal impact factor relates to a specific time period; it is
possible to calculate it for any desired period.
 The Journal Reference Reports (JRR) show rankings of journals by
journal impact factor, by discipline, such as mechanical
engineering or human resource management.
 In a given period (Yearly/Half-yearly/Quarterly/Monthly), the
journal impact factor of a journal is the average number of
citations received per paper published in that journal during the
one or two (one or more) preceding periods.
Impact Factor Calculation

5.  For Ex: if a journal has an impact factor of 5 in 2009, then its
papers published in 2007 & 08 received 5 citations each on
average. The 2009 impact factor of a journal is calculated as
follows:
 A = number of times articles published in 2007 & 08 were cited by
journals, books, patent document, thesis, project reports,
newspapers, conference/seminar proceedings, documents
published in internet, notes and any other approved documents
during 2009
 B = total number of "citable items" published by that journal in
2007 & 08. ("Citable items" are usually articles, reviews,
proceedings, notes or any other documents pre-reviewed before
publishing it)
Impact Factor Calculation of JIF

6. Then the JIF Yearly, i.e., for 2009 Impact Factor = A/B.
 New journals, which are indexed from their first published issue,
will receive an impact factor after indexing it immediately.
 For Example, a journal published fist issue in June 2011, can get
Journal Impact Factor for July 2011 onwards.
Impact Factor Calculation of JIF

7.  The impact factor is used to compare different journals within a
certain field.
 The Web of Science indexes more than 11,000 science and social
science journals.
 It is possible to examine the impact factor of the journals in which a
particular person has published articles.
 This use is widespread, but controversial. Garfield warns about
the "misuse in evaluating individuals" because there is "a wide
variation from article to article within a single journal".
 IF have a large, influence on the way published scientific research is
perceived & evaluated. Some companies are producing false IF.
Uses of Impact Factor

8.  Numerous criticisms have been made regarding the use of IFs.
 The impact factor might not be consistently reproduced in an
independent audit.
 There is also a more general debate on the validity of the impact
factor as a measure of journal importance and the effect of policies
that editors may adopt to boost their impact factor.
 Other criticism focuses on the effect of the impact factor on behavior
of scholars, editors and other stakeholders.
 Others have criticized the impact factor more generally on the
institutional background, claiming that what is needed is not just its
replacement with more sophisticated metrics but a democratic
discussion on the social value of research assessment and the
growing precariousness of scientific careers.
Criticisms of impact factor