Normal distributions are symmetrical and create a bell-shaped curve. If your process does not have a normal distribution, you will need to determine why not. If the process is bound by 0 on one side, it may be normally distributed, but not appear that way. For more information on non-symmetrical distributions, select: Study the shape
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The distribution appears to be normal. Have you calculated capability indices?
Yes No
You may wish to create a histogram with a curve to determine if your process has a normal distribution. Perform capability analysis to learn if the process is capable of producing output that meets specification requirements. For more information, select:
Does the histogram have a bell shape?
Yes No Not Sure
There are no special causes of variation and the process appears to be in control at this time. Have you created a histogram and calculated capability statistics for this process?
The process is not in control. Investigate the cause(s) of the variation and determine if effects are good or bad. For more information, select:
Declare the system stable or unstable and respond to the information on the control chart.
Are there any nonrandom patterns in the X-bar, X, or median chart?