Bartlett's test was performed for the GEAR.DAT data set. The data set contains 10 measurements of gear diameter for ten different batches for a total of 100 measurements.
H0: σ12 = σ22 = ... = σ102
Ha: At least one σi2 is not equal to the others.
Test statistic: T = 20.78580
Degrees of freedom: k - 1 = 9
Significance level: α = 0.05
Critical value: Χ 21-α,k-1 = 16.919
Critical region: Reject H0 if T > 16.919
We are testing the null hypothesis that the batch variances are all equal. Because the test statistic is larger than the critical value, we reject the null hypotheses at the 0.05 significance level and conclude that at least one batch variance is different from the others.