The basis of a method whereby the distribution of a particular attribute in a population can be calculated from its mean occurrence in a random sample of the population, provided that the population is large and the probability that the attribute will occur is less than 0.1. For a given mean the distribution can be calculated, giving the probabilities that a sample will contain 0, 1, 2, 3,…examples of the particular attribute. The distribution is named after the French mathematician S. D. Poisson (1781–1840).
http://mathworld.wolfram.com/PoissonDistribution.html Explanation of the Poisson distribution.
Subjects: Biological Sciences.