What is a Poisson random variable?
A Poisson random variable refers to the number of successes in a Poisson experiment. We might be interested in the number of phone calls received in an hour by a receptionist. Suppose we knew that she received 1 phone call per hour on average. We might ask: What is the likelihood next hour that she will receive 4 phone calls next hour. If we treated this as a Poisson experiment, then the value of the Poisson random variable would be 4. (And the average rate of success would be 1.
