Citation Analysis part#3

A high volume of self-citation is not unusual or unwarranted in journals that are leaders in a field because of the consistently high quality of the papers they publish, and or because of the uniqueness or novelty of their subject matter. Ideally, authors reference the prior publications that are most relevant to their current results, independently of the source journal in which the work was published.

However, there are journals where the observed rate of self-citation is a dominant influence in the total level of citation. For these journals, self-citation has the potential to distort the true role of the tittle as a participant in the literature of its subject.

Eighty per cent of all journals listed in the JCR Science Edition have self-citation rates less than or equal to 20%. This shows that self citation is quite normal for most journals and id expected.

Significant deviation from this normal rate, however, prompts an examination by Thomson Reuters to determine if excessive self-citations are being used improperly, the journal's Impact Factor (IF) will not be published and the journal may be considered for deselection from the Web of Science.

Citation Analysis part#2

Citation analyses takes place on at least two levels. We look for citations to the journal itself, as expressed by Impact Factor (IF) and/or total citations received. We also examine the citation record of the contributing authors, a useful study in evaluating new journals where a citation history at the journal level does not yet exist.


Likewise, established journals that are not covered are often re-evaluated. These journals can experience new growth in citation impact resulting from changes such as translation into English, change in editorial focus, change in Publisher, medium, etc.


Because Thomson Reuters captures all cited references from each of the 9,300 journals covered, citation information is available on journals not covered as well as those that are covered. Self-citation rates are also taken into consideration. The self-cited rate relates a journal's self citations to the number of time it is cited by all journals, including itself.


For example, journal X was cited 15,000 times by all journals, including the 2,000 times it cited itself. Its self-cited rate is 2/15 or 13.3%

Citation Analysis

The Thomson Reuters evaluation process is unique in that our editors have a wealth of citation data available to them. The importance of interpreting and understanding these data correctly cannot be emphasized too strongly. using quantitative citation data to measure impact is meaningful only in the context of journals in the same general discipline.


For example, smaller fields like crystallography do not generate as many articles or citations as do larger fields such as biotechnology or genetics. Likewise, in some areas, particularly in the arts and humanities, it may take a relatively long time for an article to attract a meaningful number of citations.


But in other areas, such as the life sciences, it is not unusual for citations to accrue rapidly and peak after two or three years. These facts must be taken into consideration if citation data are to be used correctly.

International Diversity

Thomson Reuters editors look for International Diversity among the contributing authors and the journal's editors and Editorial Advisory Board members. This is particularly important in journals targeting an international audience. Today's scientific research takes place in a global context and an internationally diverse journal is more likely to have importance in the international community of researchers.


As the global distribution of Web of Science expands into virtually every region on earth, the importance of regional scholarship to our emerging regional user community also grows. Selection criteria for regional journals are the same as for international journals although citation analyses play a somewhat different role in the outcome.


For example, the importance of the regional journal would be measured more in terms of the specificity of its content. Will it enrich our coverage of a particular subject or provide studies with a specific regional perspective?


Many excellent regional journals target a local rather than an international audience. therefore, the emphasis on extensive international diversity is less than for internationally focused journals.


All regional journals selected must be publishing on time, have English- language bibliographic information (title, abstract, keywords) and be peer reviewed. Cited references must be in the Roman alphabet.

Editorial Content

As mentioned above, an essential core of scientific literature forms the basis for all scholarly disciplines. However, this core is not static- scientific research continues to give rise to specialized fields of studies, and new journals emerge as published research on new topics achieves critical mass.


Our editors determine if the content of a journal under evaluation will enrich the database or if the topic is already adequately addressed in existing coverage. With an enormous amount of citation data readily available to them, and their daily observation of virtually every new scholarly journal published, our editors are well positioned to spot emerging topics and active fields in the literature.