• The Poisson distribution, named after the French mathematician Siméon Denis Poisson, can be used to estimate how many times an event can occur within “X” time periods.

  • Poisson distributions are used when the variable of interest is a discrete countable variable.
  • Many economic and financial data appear as counting variables, such as how many times a person becomes unemployed in a given year, allowing them to be analyzed using a Poisson distribution.