True or False, explain your answers (d) (5pts) For two random variables X and Y suppose...
True or False, explain your answers
(d) (5pts) For two random variables X
and Y suppose E[XY ] = 6 and
E[X] = −2. Then
we have E[Y ] = −3 if X and
Y are negatively correlated. (T, F)
Homework Answers
For two random variables X and Y suppose E[XY ] = 6 and E[X] =
−2. Then
we have E[Y ] = −3 if X and Y are negatively correlated. The
statement is "false".
Explanation: covariance [X, Y] = E[X, Y] - E[X] E[Y]
= 6 - [-2][-3]
= 6-6
=0
This means there is zero Covariance. This implies they are Uncorrelated.
Add Answer to:
True or False, explain your answers
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and Y suppose...
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