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Is the expected value the derivative of the moment generating function?

User Deekay
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Final answer:

The expected value is the first derivative of the moment generating function evaluated at 0, revealing that the expected value is obtained by differentiation of the MGF.

Step-by-step explanation:

The question concerns whether the expected value is the derivative of the moment generating function (MGF) in the context of probability and statistics. The expected value of a random variable, symbolized by E(X), is the long-term average of its possible values, weighted by their respective probabilities. This value is central to probability theory and has immense practical importance in various fields, including finance and engineering.



In mathematics, the moment generating function (MGF) of a random variable is a way to encode all the moments (expected values of powers) of the random variable into a single function. By taking derivatives of the MGF and evaluating them at 0, we can find the moments (including the expected value) of the distribution. Specifically, the first derivative of the MGF evaluated at 0 gives us the expected value (E(X)) of the random variable X. This means that yes, the expected value is indeed the first derivative of the MGF at the point 0.

User MillsJROSS
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