When r = 0, the best estimate of variable Y from a known variable X is…
a. the standard deviation of X
b. the standard deviation of Y
c. Mean of X
d. Mean of Y
Linear regression equation is - Y = b0 + b1X.
Where, b0 = & b1 =
Here, given that r = 0.
So, it implies that value of b1 also becomes 0.
Now, we have b0 = = =
Hence, linear regression equation becomes as -
Y = b0 + 0(X)= b0 = ........ ( since, b1 = 0)
Hence, best estimate of variable Y from known variable X is mean of y.
Option D is correct.
When r = 0, the best estimate of variable Y from a known variable X is…...
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