As a result, for highly occupied states the standard deviation of the particle number of an energy level is very large, slightly larger than the particle number itself: formula_53. This large uncertainty is due to the fact that the probability distribution for the number of bosons in a given energy level is a geometric distribution; somewhat counterintuitively, the most probable value for "N" is always 0. (In contrast, classical particles have instead a Poisson distribution in particle number for a given state, with a much smaller uncertainty of formula_54, and with the most-probable "N" value being near formula_55.)