Page 214 - Six Sigma Demystified
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194 Six SigMa DemystifieD
Individual 95% Confidence Intervals (CIs) for Mean Based on Pooled Standard
Deviation (SD)
Level N Mean SD ——-+————-+————-+————-+——
Product A: 6 161.67 3.01 (——*——)
Product B: 6 178.83 3.37 (——*——)
Product C: 6 162.33 3.33 (——*——)
Product D: 6 176.17 3.87 (——*——)
——-+————-+————-+————-+——
162.0 168.0 174.0 180.0
Pooled SD = 3.41
Excel
Menu: Data\Data Analysis\ANOVA: Single Factor; example is grouped by columns.
Result
SummAry
Group Count Sum Average Variance
Product A 6 970 161.6667 9.066667
Product B 6 1073 178.8333 11.36667
Product C 6 974 162.3333 11.06667
Product D 6 1057 176.1667 14.96667
ANOVA
Source of SS df MS F p Value F crit
variation
Between 1464.167 3 488.0556 42.01339 8.03E – 09 3.098393
groups
Within 232.3333 20 11.61667
groups
Total 1696.5 23
