Is This Moment Generating Function Expression Correct?

AI Thread Summary
The moment generating function expression presented is debated regarding its correctness, particularly in relation to the conditions under which it holds true. It is suggested that the expression is valid only if the moment generating function is exponential, aligning with a Taylor expansion. This holds for specific cases like a Wiener process but may not be applicable in general scenarios. The discussion emphasizes the importance of the underlying distribution when evaluating the moment generating function. Further exploration of the final form is encouraged to clarify its implications.
donutmax
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Is the following correct?

M(t)=1+t\mu'_1+\frac{t^2}{2!}\mu'_2+\frac{t^3}{3!}\mu'_3+... =\sum_{n=0}^{\infty} \frac {E(Y^n)t^n}{n!}

where
\mu'_n=E(Y^n)
 
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I think that will only be true if your moment generating function is an exponential - in which case you are just doing a Taylor expansion. This is true for a Wiener process - but I don't think the relation you have holds in general.

Regards,
Thrillhouse86
 
<br /> m_Y(t) = E(e^{ty}) = \int e^{ty} \, dF(y) = \int \sum_{n=0}^\infty \frac{(ty)^n}{n!}\,dF(y) = \sum_{n=0}^\infty \left(\int \frac{(ty)^n}{n!} \, dF(y) \right)<br />

What do you get from working with the final form above?
 
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