Measures of research impact can be useful for promotion, grant applications, for choosing which journals to publish in, or for choosing which partners to collaborate with. This guide outlines some ways in which research impact can be measured. Much of the available data is produced by analysis of citation counts.
Journal ranking and impact data allows you to evaluate and compare journals.
Author ranking measures include the h-index, a measure that attempts to measure both the scientific productivity and the apparent scientific impact of a scientist.