Question: In my opinion there are four main steps to determine if a process is statistically stable. They are as follows:

- First, review your data and determine if there are conditions that aren't normal. If less than normal conditions are identified test the data and re-check its predictability.

- If some of the data is out of control and varies from the majority of the data see if any factors existing when you did your data sampling.

- Check for numerous processes and distributions--if located separate it and check each part individually.

- Lastly, check your averages over longer periods of tiMeand use an i-chart to track data in a determined period of time. Examine your process and see if you can find one period of time that best makes your process more predictable.