Journal Impact Factor

During the second world war, the USA and the UK create research centers. Their aim is to industrialize scientific discovery to increase the pace of innovation for military applications. From that point on, the figure of the lonesome wizard in his ivory tower gives way to the salaryman working within a team, a laboratory and an Institute. The Research Unit was born.

In this modern structure, science evolves into a collective and standardized activity. The laboratory is no longer a cabinet of wonders or a private workshop, like those of Lavoisier or Newton. Instead, it becomes a production unit organized around teams, stakeholders, deliverables and measured outcomes.

Institutions like the Massachusetts Institute of Technology (MIT) or the Los Alamos National Laboratory, created for the Manhattan Project, symbolize this transformation. In France, the Centre National de la Recherche Scientifique (CNRS) is created in 1939.

In this modern area, the successful scientist is, above all, a productive one. But what does productivity mean in science? Peer-reviewed publications in scientific journal. The more you publish, the more visible and fundable you become. In 1942, the sociologist Logan Wilson coins the mantra Publish or Perish, capturing the pressure on academics to continually produce papers. Later, in 1962, Eugene Garfield introduces the metrics to evaluate journal and indirectly their authors: the Impact Factor.

Definition

The Impact Factor (IF) of a scientific review is given by the ratio of number of citations divided by the number of issues in the last two years.

$$ \text{IF} = \frac{n_{\text{citations}}}{n_{\text{publications}}} $$

• $n_{\text{citations}}$ the number of citations in the current year to items published in the previous 2 years
• $n_{\text{citations}}$ the number of substantive articles and reviews published in the same 2 years

Note: self-citations within the same review are considered as citations as well.

What is a good Impact Factor?

• > 10 is excellent.
• > 5 is awesome.
• > 2 is good.
• Any scientific work is respectable.

Keep in mind that Impact Factor depends mostly on the considered field. IF reflects the pace and volume of publishing in a field. In Physics for instance, the pace of publications is slower than in Medicine. So, the IF in Physics will always be lower than in Medicine as they are less publications.

The language matters a lot. English is the lingua franca of science. As a result, any publications that are not written in english will have a low Impact Factor.

The choice of key words to spin the publications is not neutral. Using emerging and hot terms e.g. machine learning will boost the visibility of the publications, then its citation rate, then the Impact Factor of the journal. Many scientists reframe their writting to fit trends and increase their IF.

Last but not least, publishing is a competition and the performance is the Impact Factor. In consequences, institutions adopt publication strategy to optimize their metrics. The Impact Factor of a journal can also be indirectly influenced by the institutional affiliation of its authors.

Why does Impact Factor matter?

• Academic legitimacy: Publishing in a high Impact Factor journal is considered a mark of research quality and visibility.
• Career: Performance of a scientist is measured with the Impact Factor of the journals where they publish. This also influences rankings on academic platform like ResearchGate.
• Ranking of your Institution: Performance of University is measured with the Impact Factor of the publications produced by its affiliated scientists. The Shangai Ranking is the most important global university ranking. Used criteria are Nobel Prizes, Fields Medals and the number and IF of scientific publications.

Examples of Journal Impact Factor

They are 12,265 ranked journals with IF from 0.1 to 244.6.

See the journals in which I have published in the publications section.

References

• Journal Impact Factor ranking: Scimago Journal & Country Rank
• Academic ranking of World Universities: Shangai Ranking
• The history of the CNRS: ComiteHistoireCNRS

The History and Meaning of the Journal Impact Factor

Eugene Garfield

JAMA. 2006 January 04. DOI: 10.1001/jama.295.1.90

The Academic Man

Logan Wilson

A Study in the Sociology of a Profession, 1942. ISBN-13: 978-1138534018

Published on January 20, 2016

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Relevant Tags

• society 

About the Author

Pierre-Edouard Guerin

Bioinformatician

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