Need help with that problem

lundi 26 janvier 2015

Hi there, I need help to solve that problem.



Suppose that the conditional distribution of N, given that Y = y, is Poisson with mean y. Further suppose that Y is a gamma random variable with parameters (r, λ), where r is a positive integer.



(a) Find E[N].

(b) Find Var(N).

(c) Find P(N = n)




My work so far.

a) E(N)=E(E(N|Y)=E(Y)=rλ

b)Var(N)=E(Var(N|Y))+Var(E(N|Y))=E(Y)+Var(Y)=rλ+rλ ^2



Is my work correct so far, and also I am not sure how to start part c.



Thanks for your help!





Need help with that problem

0 commentaires:

Enregistrer un commentaire

 

Lorem

Ipsum

Dolor