Russel-Research-Method-in-Anthropology

600 Chapter 20
x 1,2...n
n 1,2...n
2
x total
Thus, the between-group sum of the squares is:
n total
Formula 20.5
(79.3 2 /9)(142 2 /12)(258.4 2 /16)(167.1 2 /13)8,367.005
698.721,680.334,173.162,147.888,367.005 333.09
And since:
within-group sum of squares
total sum of squaresbetween-group sum of squares
the within-group sums of square is:
56.16333,09223.07
We can now calculate s 2 between, the between-group variance, and s 2 within, the
within-group variance.
and
s 2 between
s 2 within
total between-group sums of squares
degrees of freedom between groups
total within-group sums of squares
degrees of freedom within groups
We compute the degrees of freedom between groups and the degrees of freedom
within groups as follows:
df between groups number of groups1
df within groups nnumber of groups
So, for the data in table 20.3, the df between groups is 413, and the df
within groups is 50446. Then:
and
the between-group variance333.09/3111.03
the within-group variance223.07/464.85
We now have all the information we need to calculate the F-ratio, which is:
s 2 between
s 2 within