In statistics, economics, and econophysics, the King effect refers to the phenomenon where the top one or two members of a ranked set show up as outliers. These top one or two members are unexpectedly large because they do not conform to the statistical distribution or rank-distribution which the remainder of the set obeys.
The King effect has been observed in the distribution of French city sizes (where the point representing Paris is the "King", failing to conform to the stretched exponential) and the popularity of musicians, where Cliff Richard and Elvis Presley are the outliers not fitting on a stretched exponential country populations (where only the points representing China and India fail to fit a stretched exponential). Note, however, that the King effect is not limited to outliers with a positive evaluation attached to their rank: for rankings on an undesirable attribute, there actually may exist a Pauper effect, with a similar detachment of extremely ranked data points from the reasonably distributed portion of the data set.
- "Stretched exponential distributions in nature and economy: "fat tails" with characteristic scales", J. Laherrère and D. Sornette
- "A power law tail in India's wealth distribution: Evidence from survey data", Arjun Jayadev
- "The individual success of musicians, like that of physicists, follows a stretch exponential", J.A. Davies