altmetrics is a newly developed means of measuring impact based on data from social media, such as blogs, tweets, bookmarks and downloads. Unlike citation counts, which follow the natural publication flow and are thus often slow, measures of usage based on data from social media are more immediate.
The term 'altmetrics' was coined by Jason Priem:
"altmetrics could be used in evaluating scholars or institutions, complementing unidimensional citation counts with a rich array of indicators revealing diverse impacts on multiple populations. They could also inform new, real-time filters for scholars burdened by information overload: imagine a system that gathers and analyzes the bookmarks, pageviews, tweets, and blog posts from your online networks, using your interactions with them to learn and display each day’s most important articles or posts" (Priem, 2011).
altmetrics is still in its infancy; however new applications and theories are constantly emerging which support the altmetrics initiative:
ReaderMeter visualises at author and publication level statistics on the extent to which a large group of readers is using research. The data come from Mendeley, who via their Mendeley Developers Portal allows anyone who so wishes to develop new applications using Mendeley data.
The measuring of tweets and likes in this area is also a rapidly growing trend and there are already a number of options that can be applied at personal level or to an individual publication.
See also 'altmetrics: a manifesto'
Judy Luther (25 July 2012). Altmetrics – Trying to Fill the Gap (the Scholarly Kitchen blog). http://scholarlykitchen.sspnet.org/2012/07/25/altmetrics-trying-to-fill-the-gap/
Jason Priem (21 November 2011). As scholars undertake a great migration to online publishing, altmetrics stands to provide an academic measurement of twitter and other online activity (the LSE Impact of Social Sciences blog) http://blogs.lse.ac.uk/impactofsocialsciences/2011/11/21/altmetrics-twitter/