Question

When using the Poisson distribution, which parameter of the distribution is used in probability computations? What is the symbol used for this parameter?

Answer 1

The Poisson distribution uses the shape parameter denoted by λ.

Explanation:

A Poisson distribution is used to describe the distribution of the number of events that take place in a fixed interval of time.

For instance, number of customers arriving at a bank in an hour or the number of typos encountered in a book every 50 pages.

The Poisson distribution uses the shape parameter to compute the probabilities of different events.

The shape parameter is defined as the average number of occurrence in a given time interval. It is usually denoted by λ.

The probability mass function of a Poisson distribution is:

`P(X=x)(e^(-\lambda)\lambda^(x))/(x!);\ x=0,1,2,3...`