![]() |
![]() |
The SHEWHART Procedure |
When control limits are determined from the input data, three methods (referred to as default, MVLUE, and RMSDF) are available with the MCHART statement for estimating the process standard deviation . The method used to calculate
depends on whether you specify the STDDEVIATIONS option in the MCHART statement. If this option is specified,
is estimated using subgroup standard deviations; otherwise,
is estimated using subgroup ranges. For further details and formulas, see Methods for Estimating the Standard Deviation.
![]() |
![]() |
Copyright © SAS Institute, Inc. All Rights Reserved.