  Empirical evidence suggests that elliptical galaxies hosting a radio source
may not be different from normal non-radio ellipticals. To test this
possibility, we use Monte Carlo simulations to reproduce the distribution of
radio galaxies in the radio-optical luminosity plane. The input parameters of
the simulation are the optical luminosity function (LF) of ellipticals and the
radio LF of radio galaxies, linked by a function giving the probability for an
elliptical to be a radio galaxy.
  Simulations reproduce the observations well, supporting unification of radio
and non-radio ellipticals, provided that the probability of an elliptical
hosting a radio source is proportional to the square of its optical luminosity.
  The difference of 0.5 magnitudes in average optical luminosity between FRI
and FRII radio galaxies is also explained in this framework.
