How do you determine the variance of a Poisson distribution?

1 Answer
Nov 8, 2015

The Poisson Distribution is that of a discrete random variable. Hence we use the summation procedure.

Explanation:

For any random variable X, the variance is defined as

σ2 = E(X2) -[E(X)]2.
if the random variable is a discrete random variable, we obtain
σ2 = 0x2p(x) - [0x.p(x)]2 where
p(x) =(eμμxx!) x = 0,1,2,3,-----
Finally, the answer is obtained as μ.