A mathematical relationship between the frequency and size of an event, where the frequency increase is inversely proportional to its size increase. For example, the Italian economist Vilfredo Pareto (1848–1923) observed that 80% of the land in Italy was owned by 20% of the population, and from this we get the Pareto principle or 80/20 rule. In the context of social media where user-generated content is produced by mass participation, the American new-media theorist Clay Shirky (b.1964) predicts that the most contributions will be made by a minority of people, and the most active individual contributor is likely to be twice as active as the second most active.
http://www.shirky.com/writings/powerlaw_weblog.html Power laws, weblogs, and inequality
Subjects: Media Studies.