Summary Statistics

The Summary Statistics pane may contain any of the following fields, dependant on whether the particular field is activated in the Stats tab in the Preferences dialog box :

Chart Type: The control chart that is used for analysis.

UCL: Upper Control Limit, either as calculated or as entered (if Control Limits Based On is set to a fixed value in the Define Characteristics Regions tab )

LCL: Lower Control Limit, either as calculated or as entered (if Control Limits Based On is set to a fixed value in the Define Characteristics Regions tab )

see:

X-Bar Chart Calculations

Range Chart Calculations

Sigma Chart Calculations

Individual-X Chart Calculations

Moving Range Chart Calculations

P Chart Calculations

Np Chart Calculations

U Chart Calculations

C Chart Calculations

PCL : Process Center Line, either as calculated from the data or from the midpoint of the entered control limits (if Control Limits Based On is set to a fixed value in the Define Characteristics Regions tab )

Note: PCL is the Grand Average (defined below) when X-Bar charts or Individual-X charts with Normal Curve Fit are shown, and is the Median of the fitted curve when Run Charts or Individual-X charts with non-normal curve fits are shown.

Grand Average : the overall average of the subgroups, including points removed by the Auto Drop feature.

Process Sigma: the process standard deviation, calculated using the specified control chart.

Cpk / Cp : the process capability indices Cpk and Cp

Ppk / Pp : the process performance indices Ppk and Pp

Sigma Level: the predicted long-term Sigma Level for the process, where Six Sigma equates to 3.4 DPMO

DPMO: Defects per Million Opportunities. The predicted defect rate for the process.

Percent High / Percent Low: The predicted percent beyond the upper spec (percent high) and lower spec (percent low), respectively.

Yield: The predicted yield.

Curve Fit Type: Normal or one of the Johnson distributions (Johnson Su, Johnson Sb, Johnson Sl or Johnson Sn).

K-S Test : the result of the K-S (Kolmogorov-Smirnov) goodness of fit test. Values will be between 0 and 1; values closer to 1 represent a better fit, while those close to zero represent a very poor fit.

Control Limits Based On: All Plotted Groups, or as set to a fixed value in the Define Characteristics Regions tab

Plotted Subgroups: All, Current Only, or Current + Query, based on the setting in the Define Characteristic dialog box Plotted Data tab .

Auto Drop Status: On or Off, based on the setting in the Define Characteristic dialog box Properties tab .

Ignored Subgroups: None, or the list of subgroups that were not included in the analysis

Run Tests Applied: None, All, or the list of specific Run Tests that were applied to the analysis, as specified from the Define Characteristics dialog box Run Tests tab .

Subgroup Average : the calculated mean of the selected subgroup

Subgroup Range (or Sigma ): the calculated range or sigma value of the selected subgroup.

Subgroup Active Status: Active or Inactive, based on the setting available from selecting the Current Subgroup Status option in the View menu.

Run Tests Failed: the list of applied Run Tests that were failed for this subgroup