Eigenfactor.org is a project of Bergstrom Lab at the University of Washington. The goal of Eigenfactor is to rate a journal's importance to the scholarly community. Towards that goal, Eigenfactor gathers data from around the web, including Thomson Scientific's Journal Citation Reports, to compute two numbers: Eigenfactor score (EF) and article influence (AI).
Eigenfactor score (EF) is a measure of the "journal's total importance to the scientific community."
Aritlce influence (AI) is "a measure of the average influence of each of its articles over the first five years after publication."
For more information on the methodology and data sources behind the rankings, see Eigenfactor.org's FAQ.
Altmetrics, a shortening of "alternative metrics", was first conceived on Twitter in 2010 by Jason Priem, a doctoral student who later co-founded Impactstory.org.
"Altmetrics are complementary to citation-based metrics (citation counts, Journal Impact Factor, and so on), and distinct from social media metrics (which don’t measure the attention paid specifically to research online; instead they measure the overall reach of and engagement with social media accounts) and usage statistics (which showcase only the volume of attention research has received). High-quality altmetrics make the underlying source data available (i.e. who is saying what about research) as a measure to ensure against gaming and provide context for the numbers using disciplinary and time-based percentiles." - What Are Altmetrics
Find out more about altmetrics in this guide from the University of Pittsburgh Library System.
Please give attribution to the University of Minnesota Crookston