In the bibliometric rankings, the most common criteria include the citation analysis, the impact of specialized magazines and the number of publications in refereed journals.
However, the classifications based on production of documents or scientific activity generally do not apply corrections by establishment size, so its tend to be biased to favor large universities that produce a larger mass of research papers.
Consequently, some small educational institutions or no focused to research are listed as poor quality, or not appear at all, despite enjoying high reputation in professional circles.
[6] According to the study (2011), the 10 Mexican universities with highest scientific production in articles indexed by the ISI Web of Knowledge are: The Ibero-American Ranking SIR 2012, prepared by the SCImago Research Group of University of Granada, analyzes all the scientific production present in the Scopus database developed by Elsevier in 2006-2010 and associates each publication and each citation found to the institution or institutions concerned.
"[11] In July 2010, the five best classified Mexican universities were:[12] As the name suggests, these rankings often reflect the weighted average of the opinions gathered in a survey, which often include members of the business community and whose seriousness and methodological rigor varies according to the source.