Probability - Poisson Probability

dkotschessaa
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Homework Statement



Show that the Poisson probabilities p_{0}p_{1},...can be estimated recursively by p_{0} = e^{-\lambda} and

<br /> p_{k}=(\lambda/k)*p_{k-1} k=1,2,...


Homework Equations



I know the Poisson distribution f(x, \lambda) = e^{-\lambda}\lambda^{x}/x!

But I haven't the faintest idea what is even being asked for here. It was never covered in class, our book, or any of the books I've looked through.

-Dave K
 
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dkotschessaa said:

Homework Statement



Show that the Poisson probabilities p_{0}p_{1},...can be estimated recursively by p_{0} = e^{-\lambda} and

<br /> p_{k}=(\lambda/k)*p_{k-1} k=1,2,...

Homework Equations



I know the Poisson distribution f(x, \lambda) = e^{-\lambda}\lambda^{x}/x!

But I haven't the faintest idea what is even being asked for here. It was never covered in class, our book, or any of the books I've looked through.

-Dave K

Hi dkotschessaa! :smile:

##p_k## is just another way to write ##f(k, λ)##.
What is ##f(0, λ)##?
Can you express ##f(k, λ)## in terms of ##f(k-1, λ)##?
 
Thank you, that was extremely helpful . I was also able to use this to get a value for P(X≤4) which was the next part of the question!

Regard,

Dave K
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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