Question

pei

求解b小題🙇

9. In Section 9.2.1, we discussed two dependent samples X; and Y; for i = 1,...,n. Suppose
o2, and var(Y) = o for all i = 1,...,n. In addition,
cov (X, Y) = 0 for ij. Let di = X₁ - Y₁ denote the difference of two samples.
that cov(X, Y)
= p, var (X₂)
=
(a) Find the variance of o2 = var(d;).
(b) In page 21 of the course slides, we have already provided the formula of S2. Please show
that S is an unbiased estimator of o2. That is, E(S²) = 2/1.

Answer 1

✨ 最佳解答 ✨

Alstormeria5

As below.but you didn’t post the estimator in the second question

pei

here

Alstormeria5

Here

pei

Thank you!