In order for cosmologists to discern the large-scale structure of the cosmos, it is necessary to determine the true distribution of galaxies in space. In order to do this, however, it is necessary to correct for the fact that some dim galaxies are too faint to be seen (the Malmquist bias). This correction is often obtained via a luminosity function, which gives the number density of galaxies (galaxies per unit of comoving volume) per bin of intrinsic brightness (or absolute magnitude bin). This review uses real data from the Sloan Digital Sky Survey to demonstrate one such method for obtaining the luminosity function, the Lynden-Bell/ Choloniewski method.