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Shift 3
Shift 2
Shift 1
1.501.251.000.750.50
Shift
95% Bonferroni Confidence Intervals for StDevs
Test Statistic
P-Value
0.30
0.862
0.02
0.984
Test Statistic
P-Value
Bartlett’s Te st
Levene’s Test
Test for Equal Variances for Size
FIGURE 4.25
Condence intervals for standard deviations of three shifts.
Test for Equal Variances: Size versus Shift
95% Bonferroni confidence intervals for standard deviations
Shift N Lower StDev Upper
Shift 1 20 0.671793 0.935314 1.49742
Shift 2 20 0.601368 0.837264 1.34045
Shift 3 20 0.604612 0.841781 1.34768
Bartlett’s Test (Normal Distribution)
Test statistic = 0.30, p-value = 0.862
Levene’s Test ...