, Volume 71, Issue 2, pp 233–243 | Cite as

Gamma-distribution and wealth inequality

  • A. ChakrabortiEmail author
  • M. Patriarca


We discuss the equivalence between kinetic wealth-exchange models, in which agents exchange wealth during trades, and mechanical models of particles, exchanging energy during collisions. The universality of the underlying dynamics is shown both through a variational approach based on the minimization of the Boltzmann entropy and a microscopic analysis of the collision dynamics of molecules in a gas. In various relevant cases, the equilibrium distribution is well-approximated by a gamma-distribution with suitably defined temperature and number of dimensions. This in turn allows one to quantify the inequalities observed in the wealth distributions and suggests that their origin should be traced back to very general underlying mechanisms, for instance, the fact that smaller the fraction of the relevant quantity (e.g. wealth) that agent can exchange during an interaction, the closer the corresponding equilibrium distribution is to a fair distribution.


Gamma distribution wealth inequality 


89.65.Gh 87.23.Ge 02.50.-r 


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Copyright information

© Indian Academy of Sciences 2008

Authors and Affiliations

  1. 1.Department of PhysicsBanaras Hindu UniversityVaranasiIndia
  2. 2.National Institute of Chemical Physics and BiophysicsTallinEstonia

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