Specification of the parameters of this utility function [Behavioral Economics]
As @Henry commented and according to https://meta.stackexchange.com/questions/117251/what-should-be-done-with-questions-that-have-been-self-resolved-as-a-comment-ins I made a community wiki with the answer:


  αi and βi are coefficients related to how much an individual i feels bad about being less wealthy or more wealthy than other people. max{xj−xi,0} is the difference between person j's wealth and person i's wealth if person j's wealth is higher than person i's wealth; otherwise it is 0. The division by n−1 to get an average is because there are n−1 individuals apart from person i for person i to compare to.