power law distribution

Syllable breakdown

Dictionary meaning

A statistical distribution in which the frequency of an event varies as a power of its size — very large events are rare but not as rare as a normal distribution would predict; power laws characterise city populations, wealth distributions, earthquake magnitudes, word frequencies, and internet link counts

History and origin

Power law distributions were studied in linguistics by George Zipf in the 1930s (Zipf's Law) and in social sciences by Vilfredo Pareto (Pareto distribution); complexity scientists like Barabási popularised their role in networks

Examples

• The power law distribution of city sizes means there are a few mega-cities and many small towns but almost no 'medium' cities.
• In finance, stock market crashes follow a power law distribution rather than the normal distribution assumed by classical models.

Synonyms: Pareto distribution, Zipf's law (in language), heavy-tailed distribution, scale-free distribution