Annual science and social sciences editions of journal performance metrics based on the Thomson ISI citation databases.
Journal Citation Reports is a database that allows researchers to evaluate what journals are the best home for their publications. It provides information on topics such as: whether a journal is peer-reviewed; its acceptance rate; and more.
There are several ways to explore the data: you can browse by journal; browse by category; or run custom reports.
Journal Citation Reports has a few specialized analytics that it is helpful to have the definition for:
Journal Impact Factor: Measures the influence that a journal has in its field of study. The higher the number, the more influential the journal.
Eigenfactor Score: A ranking system that evaluates a journal's influence by closely evaluating citations of its articles. Citations from highly ranked journals are weighted to have a greater impact on the Eigenfactor Score than those from lower-ranked journals. Again, the higher the Eigenfactor Score, the more influential the journal. Note, though, that the Eigenfactor Score is likely to be much lower than the Journal Impact Factor.
Normalized Eigenfactor Score: "The Normalized Eigenfactor Score is the Eigenfactor score normalized, by rescaling the total number of journals in the JCR each year, so that the average journal has a score of 1. Journals can then be compared and influence measured by their score relative to 1. For example, if a journal has a Normalized Eigenfactor Score of 5, that journal is considered to be 5 times as influential as the average journal in the JCR."