depending on the moment generating function of the random variable X : M(t)=e^(t^2 ) :find

1. p(x=2)

2.find the mean of X

3. FIND THE VARIANCE of -2x

4.find the the second moment about the origin

i don't know how i starting ??

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- August 6th 2008, 11:36 AM #1

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- August 6th 2008, 08:15 PM #2

- August 6th 2008, 08:51 PM #3
Note that the normal distribution with mean and variance has the moment generating function .

Compare this with the given moment generating function and you see that X must follow a normal distribution with and variance .

This gives you a way of checking the answers to 2. and 3.

It also lets you calculate Pr(a < X < b) were it to be asked.

- August 7th 2008, 04:51 AM #4

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- August 7th 2008, 05:00 AM #5

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- August 7th 2008, 05:09 AM #6

- August 7th 2008, 07:13 AM #7

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i'm so sorry i solve it before i open my mail and see the solution >>>

i forgot that the derivative for 2te^(t^2 ) is equal to "derivative for two multiply function " so the answer is false >>>>>

but i solve it >>>>>then i verify from your saying

thank you>>>>you're a nice man

- August 7th 2008, 07:16 AM #8

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- August 7th 2008, 04:28 PM #9

- August 8th 2008, 03:09 AM #10

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