Business Statistics

Chapter 12 | Analysis of Variance and Experimental Designs 395

TABLE 12.7

ANOVA table for Example 12.1

Source of

variation

Sum of

squares

Degrees of

freedom

Mean squares F Value

Between

columns

(treatment)

SSC 4 – 1 = 3

MSC =

59.7083

3

19.9027=

= 19.9027

MSC

43.03

MSE

F = =

Within

columns

(error)

SSE 24 – 4 = 20

MSE =

9.25

20

0.4625=

= 0.4625

Total SST 24 – 1 = 23

Step 7: Arrive at a statistical conclusion and business implication

At 95% condence level, the critical value obtained from the F table is F

0.05, 3, 20

= 3.10. The calculated value of F is 43.03, which is greater than the tabular value

(critical value) and falls in the rejection region. Hence,