Tag Archives: generating function

The binomial's variance through generating functions

In the post Binomial distribution: mean and variance, I proved that if $X$ is a binomial random variable with parameters $n$ (trials) and $p$ (probability of success) then the variance of $X$ is $np(1-p)$. If you'll notice my proof was by induction. You might ask, why would I do that? It's certainly one of the […]