Thank you to Brandi Tuttle, Duke University Medical Center Library & Archives for allowing me to use some information from her Publication Metrics Guide
This guide provides resources and instructions on how to locate and document the following types of research impact:
A unique identifier allows you to distinguish yourself from other researchers. It can be used in journal and grant submissions and it allows you to standardize your research persona ensuring that you get recognition for your work. It is now required by many funders and publishers.
The Journal Impact Factor is a measure of the frequency with which the average article in a journal has been cited in a particular year. The JCR also lists journals and their impact factors and ranking in the context of their specific field(s).
The h-index is an author-level metric that attempts to measure both the productivity and citation impact of the publications of a scientist or scholar.
The h-index is based on the highest number of papers included that have had at least the same number of citations. The value of h is equal to the number of papers (N) in the list that have N or more citations.
Thus, if the h-index for an author is 10, it means that of all his published articles, at least 10 have been cited 10 or more times.
The g-index is an index for quantifying scientific productivity based on publication record (an author-level metric). It was suggested in 2006 by Leo Egghe
Altmetrics are statistics sourced from the social Web that can be used to help you understand the many ways that your work has had an impact with other scholars, the public, policy makers, practitioners, and more. They are useful supplementary measures of impact, best used in tandem with traditional measures like citation counts. Together, the two types of metrics can illustrate the full impact of your work.
There are very clear limitations to using the different types of metrics currently produced and used. Some of the limitations to the traditional metrics are as follows: