In: Statistics and Probability
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 |
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