SIGMAS Subcommand (SPCHART command)

SIGMAS allows you to define the sigma level for a control chart. The value specified on SIGMAS is used in calculating the upper and lower control limits on the chart. It also determines the placement of reference lines on a process capability chart (/CPCHART) when the REFERENCE subcommand includes the keyword SIGMAS. You can specify a number larger than 1 but less than or equal to 10. A larger SIGMAS value means a greater range between the upper and the lower control limits. The default is 3.