Multiple Stream Process (MSP) X-Bar and R or S Group Control Chart (GCC)

Creates an X-bar and R or S group control chart for variables in the input descriptor continuous dependent Variable list. You can set the center line for the X-bar chart and sigma; also computes short-run multiple stream charts. If no categorical variable is specified, the program will compute samples from a (user-defined) fixed number of consecutive observations. Short-run charts can also be computed; if a second categorical predictor variable is specified in the input descriptor, then that variable will be used to assign samples to parts; otherwise always k (as specified by the user) consecutive samples will be assigned to consecutive parts.

General

Element Name Description
Detail of computed results reported Specifies the level of computed results reported. By default the respective chart summary is reported. If All results is requested, spreadsheet summaries for each chart, default results for runs tests, and outlier summaries are also computed and reported in results spreadsheets.
Type of X-bar chart Type of X-bar chart (how to estimate sigma; type of summary chart).
Number of obs. per sample Number of observations per sample; each consecutive set of k observations will be assigned to the same sample; if a categorical predictor is specified, then the (first) categorical predictor variable will be used to assign observations to samples.
Min. n per sample Samples with less than k number of observations will be ignored (not included in charts).
Short run chart Specifies whether the current chart is a short-run chart for multiple parts; if so, Statistica will either assign samples to parts based on the specified fixed number of samples per part, or take the second categorical predictor variable (if one is specified) to assign samples to parts.
Number of samples per part Number of samples per part (for short-run charts); if a second categorical predictor variable is specified, Statistica will determine the assignment of samples to parts from the integer codes found in that variable; otherwise, Statistica will use this parameter to assign consecutive k samples to parts.

X/X-bar Specs

Element Name Description
Applies user-defined centerline Applies user-defined centerline value for the X-bar chart; if false, compute the centerline value from the data (mean).
User-defined centerline value User-defined centerline value for X-bar chart.
Applies user-defined sigma Applies user-defined value for sigma to the X-bar group chart; if false, estimate sigma from the data (via overall R-bar or S-bar).
User-defined sigma value User-defined value of sigma (will automatically compute center line value for R/S group chart).
Lower control limit X Lower control limit for X-bar group chart; in multiples of sigma.
Upper control limit X Upper control limit for X-bar group chart; in multiples of sigma.
Show warning lines (X-bar) Show warning lines in the X-bar group chart.
Lower warning limit X Lower warning limit for X-bar group chart; in multiples of sigma.
Upper warning limit X Upper warning limit for X-bar group chart; in multiples of sigma.

R/S Specs

Element Name Description
Lower control limit R/S Lower control limit for R or S group chart; in multiples of sigma (R/S).
Upper control limit R/S Upper control limit for R or S group chart; in multiples of sigma (R/S).
Show warning lines (R/S) Show warning lines in the R or S group chart.
Lower warning limit R/S Lower warning limit for R or S group chart; in multiples of sigma (R/S).
Upper warning limit R/S Upper warning limit for R or S group chart; in multiples of sigma (R/S).

Process Capability

Element Name Description
Creates Cpk, Ppk, etc Creates process capability and performance indices (summaries) for each process (variable).
Type of specification limits Type of specification limits: Two-sided: Nominal plus/minus delta; Nominal, lower, Upper; One-sided: Lower, nominal; Nominal, upper.
Nominal value (for spec. limits) Nominal value, for process capability computations for each process (variable).
Delta value (for spec. limits) Value of delta, for defining specification limits as nominal plus/minus delta.
Lower specification limit Lower specification limit; not applicable if Type of specification limits is equal to Nominal Upper (one-sided).
Upper specification limit Upper specification limit; not applicable if Type of specification limits is equal to Lower Nominal (one-sided).
Show specs in chart Show process specification limits in the X or X-bar group chart.

Displays

Element Name Description
Formats for values on axes Select how to determine the display format of scale (axis) labels in control charts; choose From variable formats to format the scale (axis) labels using the display format of the respective variable in the plot; use Number of digits to specify a fixed number of digits for the display format.
Number of digits for scale Specifies the number of digits for the display format, for scale (axis) labels in charts; this options is only applicable if the Formats for values on axes option is set to Number of digits.
Number of digits values Specifies the number of digits to be used for displaying numbers (values other than scale or axes values for charts) in various charts and results tables
Process capability, n of digits Specifies the number of digits to be used for displaying process capability indices and related statistics.
Highlight consecutive runs Highlights consecutive runs of maximum plot points or consecutive runs of minimum plot points from the same stream at least as long as the number r specified in the edit field. For example, if the value of r is equal to 4, then in the plot, runs of at least 4 consecutive samples with maximum values or minimum values from the same stream will be highlighted.
Run length Specifies the minimum length of a run to be highlighted in the multiple stream (group) chart.