
344 Quality management for organizations using Lean Six Sigma techniques
This illustrates the difculty in using visual, intuitive weighting to make decisions.
What if there were more observations, what if there were fewer, how large does the dif-
ference really need to be, etc. There are two mistakes that can be made in answering the
question as to whether the lines being compared are really different:
• You decide that there is a difference between the two lines, but there really is no
difference.
• You decide that there is no difference between the two lines, but there really is a
difference.
In general, the same two mistakes can be made in ...