  In this paper we derive the maximum entropy characteristics of a particular
rank order distribution, namely the discrete generalized beta distribution,
which has recently been observed to be extremely useful in modelling many
several rank-size distributions from different context in Arts and Sciences, as
a two-parameter generalization of Zipf's law. Although it has been seen to
provide excellent fits for several real world empirical datasets, the
underlying theory responsible for the success of this particular rank order
distribution is not explored properly. Here we, for the first time, provide its
generating process which describes it as a natural maximum entropy distribution
under an appropriate bivariate utility constraint. Further, considering the
similarity of the proposed utility function with the usual logarithmic utility
function from economic literature, we have also explored its acceptability in
universal modeling of different types of socio-economic factors within a
country as well as across the countries. The values of distributional
parameters estimated through a rigorous statistical estimation method, along
with the $entropy$ values, are used to characterize the distributions of all
these socio-economic factors over the years.
