Question

Suppose the random variables X, Y and Z are related through the model

Y = 2 + 2X + Z,

where Z has mean 0 and variance σ2 Z = 16 and X has variance σ2 X = 9. Assume X and Z are independent, the find the covariance of X and Y and that of Y and Z. Hint: write Cov(X, Y ) = Cov(X, 2+2X+Z) and use the propositions of covariance from slides of Chapter 4.

Suppose the random variables X, Y and Z are related through the model Y = 2 + 2x + Z, where Z has mean 0 and variance o2 = 16

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Answer #1

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