Question

In: Statistics and Probability

Consider the following sample of four observations of variables Y and Z Y 3 6 5...

Consider the following sample of four observations of variables Y and Z

Y

3

6

5

9

Z

9

12

13

16

The sample covariance of Y and Z is: (round to two decimal places)

a.

6.25

b.

7.55

c.

5.13

d.

6.83

e.

4.55

Solutions

Expert Solution

Dat Formula : Sample CoV (Y,Z) = E(Yi - 7) + (zi- Z) N-1 Y;- } Z; - -2.75 -3.5 E (71-7), (2;-2) 9.625 - 0.125 -0-375 11.375 12 -0.5 13 0.25 -0.75 3.25 3.5 Total 2-2005 50 7 = Iyi = 5.75 Ζ - ΣΖ, 12.5 4 El Y; -(2;-) = 20.5 N = 4 Hence N-1 =3 put all the values in formula, we get COV (Y,Z) = 20.5 = 6.8333 = 16.83 1 Hence option @ 6.83 D is the answer


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