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#1 2011-04-19 13:16:08
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
moment generating function
how to find E(X) and Var(x) using the Mx(t) ?
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#2 2011-04-19 13:18:04
- blurguy
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- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
0.16/(0.16-t)
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#3 2011-04-19 15:46:35
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
Hi blurguy;
Welcome to the forum! Bear with me I have not done one of these in a long time. Then:
E(X) = M'(0)
E(X^2) = M''(0)
V(X) = E(X^2) - E(X)^2
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#4 2011-04-19 18:44:19
- blurguy
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- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
bobbym
sorry
E(X) = M'(0)<--why zero how you culculation? please..
E(X^2) = M''(0)
V(X) = E(X^2) - E(X)^2
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#5 2011-04-19 18:48:04
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
That is the problem I can not quite make out what you are asking here. What is the moment generating function that you want?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#6 2011-04-19 18:55:51
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
yes...This is a problem from me because I can not send a question by copy and paste from pdf file ... becouse can not read ... can you give for guidance
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#7 2011-04-19 19:09:00
- blurguy
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- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
the question link from here
http://www.mediafire.com/file/02jh8u4sx46jzr9/Final%20Exam%20QMT400%20October2010.pdf
check question 6 there are this question
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#8 2011-04-19 19:25:46
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
I can not answer to questions 6 and 10 please check the link file
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#9 2011-04-19 19:32:16
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
I have downloaded the file. Please hold on.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#10 2011-04-19 19:43:40
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
okey i'm waiting,
becouse all I ask in the forum today and attach the file to be sent a link all submit answers by today
I cried so bobby and any person can help
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#11 2011-04-19 19:52:29
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
E(X) = M'(0) = 6.25
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#12 2011-04-19 19:58:04
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
question 10 "marginal distribution"?
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#13 2011-04-19 20:08:24
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
Hi blurguy;
One thing at a time please, I am still not finished with V(x) for this question.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#14 2011-04-19 20:21:25
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
okey :)sorry
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#15 2011-04-19 20:59:41
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
E(X^2) = M''(0)
V(X) = E(X^2) - E(X)^2
Putting a 0 into the RHS.
E(X^2) = M''(0)=78.125
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#16 2011-04-19 21:46:41
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
Okay for 10 a)
As far as I know this is the marginal distribution of x
This is the marginal distribution of y
For 10 b)
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#17 2011-04-19 22:33:24
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
okey thanks...
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#18 2011-04-19 23:15:27
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
Hi blurguy;
I cannot read 10 c) so I am unable to help on that one.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#19 2011-04-19 23:47:10
- gAr
- Member
- Registered: 2011-01-09
- Posts: 3,482
Re: moment generating function
Hi,
10 c)
Last edited by gAr (2011-04-19 23:47:46)
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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#20 2011-04-19 23:49:41
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: moment generating function
Thanks gAr, I could not make out the character between the 3 /2 and the x.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#21 2011-04-19 23:59:25
- gAr
- Member
- Registered: 2011-01-09
- Posts: 3,482
Re: moment generating function
Hi bobbym,
You're welcome.
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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#22 2011-04-20 02:46:45
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
it's okey bobbym
I am very proud of the actions you are willing to help
and also in you gar 
subjec statistic from me is killer, now this week from making more homework
may becouse final exam this sunday April 24th.
i hope you all do not mind if I asked many questions on this week
guide line and the answer from the forum more help me now
i love this forum
thanks a lot
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#23 2011-04-20 02:57:42
- gAr
- Member
- Registered: 2011-01-09
- Posts: 3,482
Re: moment generating function
Hi blurguy,
You're welcome.
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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#24 2011-04-20 05:27:40
- blurguy
- Member
- Registered: 2011-04-19
- Posts: 35
Re: moment generating function
gar....
please help this question also (http://www.mediafire.com/file/r0uzrkfc8dfam8a/TEST2QMT400% 20sem1% 202011.pdf)
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#25 2011-04-20 06:41:38
- gAr
- Member
- Registered: 2011-01-09
- Posts: 3,482
Re: moment generating function
Hi,
I don't know 1)
2)
But I'd like bobbym or anyone to verify it!
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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