Short answers, pulled from the story.
The capital letters S, C, and I represent Scientific Influence while the remaining letters m-a-g-o have no specific meaning. The research group at the University of Granada developed this metric under the Scimago Lab label to measure scholarly impact beyond simple citation counts.
An iterative algorithm distributes prestige values among journals until reaching a steady state by transferring achieved prestige through citations over time. This method mirrors the PageRank algorithm used for web pages but applies it to academic networks to capture source quality rather than just reference volume.
The Scopus database serves as the foundation for all SCImago Journal Rank calculations because the Scimago Lab relies exclusively on Scopus indexed documents. Web of Science provides the data for the competing Eigenfactor score instead creating inherent differences between the resulting metrics due to coverage gaps.
Nature holds the number 17 spot in SJR but sits at position 56 in the H index list while New England Journal of Medicine ranks 56th by SJR yet claims second place in H index standings. These discrepancies highlight how different metrics prioritize various aspects of scholarly influence such as breadth of impact versus specific high-impact circles.