Zero-inflated Poisson distribution
= Zero-inflated Poisson distribution
{c}
A zero-inflated Poisson distribution is a mixture of a point mass at zero and a <Poisson distribution>. If the Poisson component has weight $\pi$ and mean $\lambda$, then its mean is $\pi\lambda$ and its variance is $\pi\lambda+\pi(1-\pi)\lambda^2$.