Process Capability Analysis Setup--Raw Data - Raw Data Tab

Select the Raw data tab of the Process Capability Analysis Setup--Raw Data dialog box to access options to select the variables for the analysis and optional grouping variable with sample codes (if the data consist of multiple samples, such as if the data were collected to produce a quality control chart).

Variables

Click the Variables button to display the standard variable selection dialog, in which you select the variables with the process measurements of interest, and an optional grouping variable with codes to identify to which sample each observation belongs. If a grouping variable is specified, then Statistica will compute capability indices (based on the inherent variation) and performance indices (based on the total variation; see ASQC/AIAG, 1991).

Process specs

Click the Process specs button to display the Enter/edit specification limits dialog box, in which you specify the process (engineering) specification limits from which the capability indices (such as Cpk) and performance indices (such as. Ppk) will be calculated. Note that the Process specs button is only available after Variables have been selected.