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Revision difference : Poisson random variable
Version 4 Version 3
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$X$ is a \textbf{Poisson random variable} with parameter \textbf{$\lambda$} if\\ $X$ is a \textbf{Poisson random variable} with parameter \textbf{$\lambda$} if\\
\par \par
$f_X(x) = \frac{e^{-\lambda} \lambda^x}{x!}$, $x=\{0,1,2,...\}$ \\ $f_X(x) = \frac{e^{-\lambda} \lambda^x}{x!}$, $x=\{0,1,2,...\}$ \\
\par \par
Parameters:\\ Parameters:\\
\par \par
\begin{list}{$\star$ }{} \begin{list}{$\star$ }{}
\item $\lambda > 0$ \item $\lambda > 0$
\end{list} \end{list}
\par \par
Syntax:\\ Syntax:\\
\par \par
$X\sim Poisson(\lambda)$\\ $X\sim Poisson(\lambda)$\\
\par \par
Notes:\\ Notes:\\
\par \par
\begin{enumerate} \begin{enumerate}
\item $X$ is often used to describe the ocurrence of rare events. It's a very commonly used distribution in all fields of statistics. \item $X$ is often used to describe the ocurrence of rare events. It's a very commonly used distribution in all fields of statistics.
\item $E[X] = \lambda$ \item $E[X] = \lambda$
\item $Var[X] = \lambda$ \item $Var[X] = \lambda$
\item $M_X(t) = e^{\lambda (e^t - 1)}$ \item $M_X(t) = e^{\lambda (e^t - 1)}$
\end{enumerate} \end{enumerate}