Question

For a time series data set in a linear model, we expect Cov( u1, u2 )...

For a time series data set in a linear model, we expect Cov( u1, u2 ) to be

A.

zero.

B.

a random variable.

C.

nonzero.

D.

none of the above

0 0
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Answer #1

In the case of a linear model, the covariance between two error terms is simply zero. Hence the answer is:

{Additional note - If it's non-zero then the linear model suffers from autocorrelation}

Let me know in the comments if anything is not clear. I will reply ASAP! Please do upvote if satisfied!

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