Poisson Distribution

Poisson Distribution:

Let X be a discrete random variable where probability of X = x is given by

the probability distribution of X is said to be Poisson distribution with parameter m. Here m is mean of the distribution. Poisson distribution is a limiting form of binomial distribution where p is very small and n is large enough such that np = m (Constant).

Mean, Variance and Standard Deviation of Poisson Distribution:

Mean:

Second Moment about origin:

Second Moment about mean:

Variance:

Standard Deviation: