Let X and Y be random variables, and a and b be constants a Prove that Cov(aX, bY ) ab Cov(X,Y ) b Prove that if a 0 and b 0, then aX,bY X,Y Conclude that the correlation coefficient is unaffected by changes in units ...

a Cov aXbY aXbY aX bY abXY a X b Y a ...

Let X and Y be random variables, and a and b be constants. a. Prove that Cov(aX,

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Let X and Y be random variables, and a and b be constants.
a. Prove that Cov(aX, bY ) = ab Cov(X,Y ).
b. Prove that if a > 0 and b > 0, then ρaX,bY = ρX,Y. Conclude that the correlation coefficient is unaffected by changes in units.

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Statistics For Engineers And Scientists

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Question Posted: May 17, 2016 07:39 AM

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Let X and Y be random variables, and a and b be constants. a. Prove that Cov(aX,

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