1. Let Z = (Z1, Z2, Z3) be a vector with i.i.d. N(0, 1) components.
Let r be a constant with 0 < r < 1. Define X1 = √ rZ1 + √ 1 − rZ2 and X2 = √ rZ1 + √ 1 − rZ3.
(a) Give the distribution of X1 and the distribution of X2. Find Cov(X1, X2).
(b) Give the matrix A so that the vector X = (X1, X2) is a transform X = AZ. Give the distribution of X and its covariance matrix.
1.
(a)
According to the question,
&
Then,
Therefore ,
&
Now,
Also,
Then,
So,
(b)
Define,
and
Then , A is 2 x 3 matrix.
i.e.
1. Let Z = (Z1, Z2, Z3) be a vector with i.i.d. N(0, 1) components. Let...
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