Let y be a 3-dimensional multivariate normal random vector with mean and variance ? = [3 0 -2]^T, V = [[2, 0, 0], [0, 2, 0], [0, 0, 1]]. Let A = 1/10 [[4, -2, 0], [-2, 1, 0], [0, 0, 10]]. (a) Describe the distribution of Ay. (b) Find E[y^T Ay]. (c) Describe the distribution of y^T Ay. (d) Find all linear combinations of y elements which are independent of y^T Ay.
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Since $y$ is a multivariate normal random vector, the linear transformation of $y$ is also a multivariate normal random vector: $$ Ay \sim N(A\mu, A\Sigma A^T) $$ Show more…
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