We approximate content popularity by a Zipf law distribution .
In general, the popularity of content is estimated using Zipf law distribution, it varies from place to place, and content to content.
The important thing for our case is that later he hypothesized the existence of more simple explanation of the Zipf law associated with a simple probability model when all symbols in the text (including white-space) appear independently of each other with certain probability.
Lerner, "The Zipf law for random texts with unequal letter probabilities and the Pascal pyramid," Izvestiya Vysshikh Uchebnykh Zavedenii.
For example, from 1998 to 2000, the 500 largest Chinese cities followed Zipf's law of urban area, but only about 250 largest cities complied with the common Zipf law of city population.
Firstly, the early studies are based on the two-parameter Zipf law, but Chinese cities follow the three-parameter Zipf's law.
explains that, the frequency of keyword occurs in number of times.
Gan, L., Li, D., Song, S., (2006) "Is the Zipf law
spurious in explaining city-size distributions?", Economics Letters, 92, pp.256-262.
Miyazima et al studied Japan's five different regional communities, they found that these areas surname distribution has the characteristic: With the changes in the population, the total number of names have also changed, and they have a power-law relationship; Surname distributed as a power-law distribution, have more individual surname species; 3 from the population, the surname ranking corresponding number of Zipf law
, in approximately a negative slope of the straight line in the double logarithmic coordinates .
* As it has been observed in the literature (see for example  and the references therein) incoming citations I(i) follow a Zipf law
. In fact, a few papers receive many citations while the majority are cited seldom.
* To find out the application of Zipf law
& Lotka's Law
* Application of Zipf Law
in the Pepper Research Publications