Binomial distribution w/ param's n & p, unbiased estimator of Var(x)

Chimchim

New member
Joined
Sep 14, 2018
Messages
4
I have successfully proved a) and b)i), but is stuck on b)ii). Please help!



The random variable X has a binomial distribution with parameters n and p.

(a) Show that \(\displaystyle P\, =\, \dfrac{X}{n}\) is an unbiased estimator of p.

Let \(\displaystyle U\, =\, n\, P\, (1\, -\, P).\)

(b) (i) Show that \(\displaystyle E(U)\, =\, (n\, -\, 1)\, p\, (1\, -\, p).\)

(b) (ii) Hence write down an unbiased estimator of Var(X).
 

Attachments

  • Screen Shot 2018-09-14 at 5.36.07 pm.jpg
    Screen Shot 2018-09-14 at 5.36.07 pm.jpg
    22.6 KB · Views: 9
Last edited by a moderator:
Top