Theorem 8.4.8. Properties of the Gamma Distribution.
For the gamma distribution from an underlying Poisson process with \(\lambda\) found by solving the Poisson mean = \(\lambda T\text{,}\)
\begin{equation*}
\mu = r \lambda
\end{equation*}
\begin{equation*}
\sigma^2 = r \lambda^2
\end{equation*}
\begin{equation*}
\gamma_1 = \frac{2}{\sqrt{r}}
\end{equation*}
\begin{equation*}
\gamma_2 = \frac{6}{r} + 3
\end{equation*}