Design and Analysis, Fourth Edition, by Keppel and Wickens Chapter 3: Variance Estimates and the F-Ratio | Stata Textbook Examples

Data from Chapter 2 from Table 2.2, page 22

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1 16 
1 18
1 10 
1 12
1 19
2 4
2 7
2 8
2 10
2 1
3 2
3 10
3 9
3 13 
3 11
end

Table 3.2, page 37. One-way analysis of variance

oneway score a

                        Analysis of Variance
    Source              SS         df      MS            F     Prob > F
------------------------------------------------------------------------
Between groups             210      2          105      7.00     0.0097
 Within groups             180     12           15
------------------------------------------------------------------------
    Total                  390     14   27.8571429

Bartlett's test for equal variances:  chi2(2) =   0.1014  Prob>chi2 = 0.951

Data from Table 3.5, page 51

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1 37
1 22
1 22
1 25
2 36
2 45  
2 47
2 23
3 43
3 75
3 66
3 46
4 76
4 66
4 43
4 62
end 

Table 3.6, page 53. One-way analysis of variance

oneway errors a

                        Analysis of Variance
    Source              SS         df      MS            F     Prob > F
------------------------------------------------------------------------
Between groups         3314.25      3      1104.75      7.34     0.0047
 Within groups          1805.5     12   150.458333
------------------------------------------------------------------------
    Total              5119.75     15   341.316667

Bartlett's test for equal variances:  chi2(3) =   1.5938  Prob>chi2 = 0.661

Data fromTable 3.6, page 57

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1 5
1 9
1 7
2 12
2 10
2 10
2 8
2 11
2 9
3 3
3 6
3 5
3 6
end 

Table 3.7, page 57. One-way analysis of variance with unequal sample size across cells

oneway score a

                        Analysis of Variance
    Source              SS         df      MS            F     Prob > F
------------------------------------------------------------------------
Between groups      62.3076923      2   31.1538462     12.98     0.0017
 Within groups              24     10          2.4
------------------------------------------------------------------------
    Total           86.3076923     12   7.19230769

Bartlett's test for equal variances:  chi2(2) =   0.3781  Prob>chi2 = 0.828