Poisson Distribution

(discrete probab dist for equations)

 

Usage:

PoissonDist (k, μ)

Definition:

exp (-μ) * μ^k / k!

= exp (-μ + k * log (μ) - log (k!))

Required:

μ > 0      k is an integer

Support:

k0

Moments:

mean = μ          σ^2 = μ

γ1 = 1 / sqrt (μ)      β2 = 3 + 1/μ

 

If events occur by a Poisson process, then the number of events that occur in a fixed time interval is described by the Poisson distribution (where m is the average number of events per unit time).