Poisson distribution

discrete probability distribution

The Poisson distribution is a probability distribution. It is named after Siméon Denis Poisson who discovered it in 1838. It measures the probability that a certain number of events occur within a certain period of time. The events need to be unrelated to each other. They also need to occur with a known average rate.

Typical Poisson distribution

Examples of this distribution are:

  • The numbers of cars that pass on a certain road in a certain time.
  • The number of telephone calls a call center receives per minute.
  • The number of light bulbs that burn out (fail) in a certain amount of time.
  • The number of mutations in a given stretch of DNA after a certain amount of radiation.
  • The number of errors that occur in a system.
  • The number of Property & Casualty insurance claims experienced in a given period of time.