Question

In computing an ANOVA involving four groups of 12 each, the following partially completed ANOVA table was given. Complete this table.

Source	SS	df	MS	F
Between	9
Within
Total	20

Answer 1

(A) degree of freedom (between) = number of groups -1

it is given that number of groups = 4

this implies

df(between) = 4-1 = 3

(B) degree of freedom (within) = total number of elements - number of groups

it is given that number of groups = 4 and total number of elements = 4*12 = 48

this implies

df(within) = 48-4 = 44

(C) df(total) = df(between)+df(within) = 3 + 44 = 47

(D) SS(within) = SS(total) -SS(between)

using the data values given in the data table

SS(within) = 20-9 = 11

(E) MS(between) = SS(between)/df(between)

this implies

= 9/3

= 3

(F) MS(within) = SS(within)/df(within)

this implies

= 11/44

= 0.25

(G) F statistics = MS(between)/MS(within)

using the calculated values

this implies

= 3/0.25

= 12