Consider the following data X 4 6 8 10 12 15 20 25 39 48 Y 1

Consider the following data:

X 4 6 8 10 12 15 20 25 39 48

Y 12 21 25 34 40 48 65 75 100 160

Calculate:

(ii) Calculate SS_xxSS_xy and SS_yy

Show your work

Solution

Step 1: Find X?Y and X2 as it was done in the table below.

Step 2: Find the sum of every column:

?X=187 , ?Y=580 , ?X?Y=16669 , ?X2=5435

Mean = 18.7, Mean Y = 58.0

Var(x) = 543.5-349.69 =193.81

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Var(Y) = 5172-3364 = 1808

coVar(xy) = 1666.9