Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y=4),  TOPIC_SOLVED

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Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y=4),

Postby zorro on Mon Jul 05, 2010 11:41 am

Question :
Suppose X and Y are independent Poisson random variable , each with the mean 1 , obtain
i) P(X+Y=4)
ii) E[(X+Y)2]
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y

Postby Martingale on Mon Jul 05, 2010 1:51 pm

zorro wrote:Question :
Suppose X and Y are independent Poisson random variable , each with the mean 1 , obtain
i) P(X+Y=4)
ii) E[(X+Y)2]


Start with this...http://en.wikipedia.org/wiki/Poisson_distribution#Properties
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y

Postby zorro on Mon Jul 05, 2010 4:04 pm

Martingale wrote:
zorro wrote:Question :
Suppose X and Y are independent Poisson random variable , each with the mean 1 , obtain
i) P(X+Y=4)
ii) E[(X+Y)2]


Start with this...http://en.wikipedia.org/wiki/Poisson_distribution#Properties

Thanks

so = = 1

P(A+B=4) = ? stuck here !!!
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y

Postby Martingale on Mon Jul 05, 2010 4:55 pm

zorro wrote:
Martingale wrote:
zorro wrote:Question :
Suppose X and Y are independent Poisson random variable , each with the mean 1 , obtain
i) P(X+Y=4)
ii) E[(X+Y)2]


Start with this...http://en.wikipedia.org/wiki/Poisson_distribution#Properties

Thanks

so = = 1

P(A+B=4) = ? stuck here !!!


From the link I provided look at "Sums of Poisson-distributed random variables"
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y

Postby zorro on Tue Jul 06, 2010 2:50 am

Martingale wrote:
zorro wrote:

Thanks

so = = 1

P(A+B=4) = ? stuck here !!!


From the link I provided look at "Sums of Poisson-distributed random variables"



I couldnt understand how to evaluate P(A+B=4) as

is it P(A+B=4) = P(A) + P(B) = 4
or is it some other way
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y

Postby Martingale on Tue Jul 06, 2010 3:33 am

zorro wrote:
I couldnt understand how to evaluate P(A+B=4) as

is it P(A+B=4) = P(A) + P(B) = 4
or is it some other way


If X is poisson 1 and Y is poisson 1

then X+Y is Poisson 2
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y

Postby zorro on Wed Jul 07, 2010 2:06 am

Martingale wrote:
zorro wrote:
I couldnt understand how to evaluate P(A+B=4) as

is it P(A+B=4) = P(A) + P(B) = 4
or is it some other way


If X is poisson 1 and Y is poisson 1

then X+Y is Poisson 2


but how should i represent it in my solution
P(A+B) = 1+1 = 2 but what about the '4'

I am having a hard time how to formulate this ? sorry or such silly questions?
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Re: Let X, Y, be ind. Poisson rand. vars; mean 1; find P(X+Y  TOPIC_SOLVED

Postby Martingale on Wed Jul 07, 2010 3:40 am

zorro wrote:
but how should i represent it in my solution
P(A+B) = 1+1 = 2 but what about the '4'

I am having a hard time how to formulate this ? sorry or such silly questions?



I think you need to review the basics of probability before you start working with random variables. I really think it will help you since your foundation in the basics is not strong enough.

Good luck!
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