Suppose that random variable X 0 = (X1, X2) is such that E[X 0 ] =...

Suppose that random variable X 0 = (X1, X2) is such that E[X 0 ] = (µ1, µ2) and var[X] = σ11 σ12 σ12 σ22 . (a matrix)

(i) Let Y = a + bX1 + cX2. Obtain an expression for the mean and variance of Y .

(ii) Let Y = a + BX where

a' = (a1, a2) B = b11 b12 0 b22 (a matrix).

Obtain an expression for the mean and variance of Y .

(ii) Suppose Y = a + bX1 + cX2 and Z = d + eX2. Calculate cov(Y, Z).

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orchestra answered 1 year ago

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