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Viewing Version 3 of 'moment generating function'
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Title of object: moment generating function
Canonical Name: MomentGeneratingFunction
Type: Definition

Created on: 2001-10-26 02:53:10
Modified on: 2004-03-08 14:15:11

Creator: mathcam
Modifier: yark
Author: yark
Author: Riemann

Classification: msc:60E05

Revision comment (for changes between this and next version):

suppress a bad autolink

Preamble:

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Content:

Given a random variable $X$, the \emph{moment generating function} of $X$ is the following function:\\
\par
$M_X(t) = E[e^{tX}]$ for $t \in R$ (if the expectation converges).
\par
\par
It can be shown that if the moment generating function of X is defined on an interval around the origin, then\\
\par
$E[X^k] = M_X^{(k)}(t) |_{t=0} $\\
\par
In other words, the $k$th-derivative of the moment generating function evaluated at zero is the $k$th moment of $X$.