  This article brings forward an estimation of the proportion of homonyms in
large scale groups based on the distribution of first names and last names in a
subset of these groups. The estimation is based on the generalization of the
"birthday paradox problem". The main results is that, in societies such as
France or the United States, identity collisions (based on first + last names)
are frequent. The large majority of the population has at least one homonym.
But in smaller settings, it is much less frequent : even if small groups of a
few thousand people have at least one couple of homonyms, only a few
individuals have an homonym.
