Six Sigma SPC OEM Products
Six Sigma and SPC (Statistical Process Control) Software
Applications
Six Sigma SPC - 2070 W. Washington St. #5
Springfield IL 62702 Ph: 217.698.0063
6 Sigma Statistical Process Control (SPC) Software for Windows
95/98/NT/2000/XP/ME

X Bar is an average of a sample.
It is the arithmetic mean. It is calculated by adding the observation, (subgroup
using stratified sampling),
values and dividing by the total number of samples. This data is typically
charted on a line control chart with the
center line being X Double Bar, (an average of the averages), and upper
control limits and lower control
limits. You can also use Pre-Control
to establish control limits.