Using the Poisson Distribution as an Approximation to the Binomial Distribution
I don’t know about you, but when I have two ways to do something, I like to choose the one that’s less work. If you don’t agree with me, feel free to skip this material. If you do, read on!
We can use the Poisson distribution to calculate binomial probabilities under the following conditions:
◆ When the number of trials, n, is greater than or equal to 20 and …
◆ When the probability of a success, p, is less than or equal to 0.05 …
The Poisson formula would look like this:
n = the number of trials
p = the probability of a success