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A
NALYZE
Control charts: Calculation of control limits
S
TEP
6 (
NEXT
): I
NTERPRETATION OF THE CONTROL CHARTS
•
Verify that the process is stable over time in position and in
dispersion (no change, no adjustment during this period).
special causes in the data used to calculate the limits
.
•
Do you detect points out of the limits? Are they
outliers?
Are they
due to the
risk
?
Decide if you prefer removing them to
recalculate narrower limits
better quality.
•
Set your limits. They will be used to monitor next results
(samples 11 to 30) and to detect any potential special
cause.
03/10/17
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