8.2.2 SP 2.2-1 Apply Statistical Methods to Understand Variation
Establish trial natural bounds for subprocesses having suitable historical performance data Collect data, as defined by the selected measures, on the subprocesses as they execute Calculate the natural bounds of process performance for each measured attribute Identify special causes of variation Analyze the special cause of process variation to determine the reasons the anomaly occurred Determine what corrective action should be taken when special causes of variation are identified Recalculate the natural bounds for each measured attribute of the selected subprocesses as necessary