Process Capability Charts

The Process Capability chart helps define the data distribution by illustrating minimum and maximum values in relation to the median. A Histogram Curve Chart is the traditional default chart type that opens in GainSeeker when a new Process Capability chart is created. However, the chart type can be changed.

Note: A minimum of five data values are needed to display this chart for a data distribution. These can come from: five or more data records with a subgroup size of one; three or more data records with a subgroup size of two; two or more data records with a subgroup size of three or four, or one or more data records with a subgroup size of five or more.

Process Capability chart options

Navigate to the Process capability chart options by following this path on the Settings tab:

Chart overrides | Charts | Multiple Charts | Process capability chart options |

You can also select default chart settings in the GainSeeker System Administration module. See Chart Defaults settings

Graph (chart) type

To change the graph type for a new or an existing chart:

• Click Graph type to display the settings. Then, click a graph type to select it.

Graph Type	Description	Display
Box and Whisker	Draws minimum and maximum values, a box based on two quartiles, and a line in the box for the median.
Box chart	Draws a box representing +3SD and -3SD, and a line in the box for the median or the mean, depending on the retrieval.
Centered Box chart	Draws a box representing +3SD and -3SD and a line in the box for the median or the mean depending on the retrieval. The box is centered on the nominal specification.
Histogram	Draws normal and non-normal curves based on the distribution. When a data curve does not display a line for the mean, it indicates non-normal data.

To change the default chart type in the GainSeeker Administration module, see Changing the default chart type

Show box values

Select the Show box values check box.

• Displays value labels for the data when this option is selected, as in this example on a traditional Box and Whisker chart:

Show data on graph

Click the checkbox preceding Show data on graph to select it.

• Shows data markers for individual data points when this option is selected.

Show entire chart element outside Spec

Click the checkbox preceding Show entire chart element outside Spec to select it.

• Allows the data illustration to display beyond the specification limits when this option is selected. Following are examples showing this option selected and not selected (the default setting). The upper spec limit in both examples has been highlighted for diagramming purposes.

Value to display on graph =

Sets the statistic or value to display on the chart when this option is selected.

1. Double-click the Value to display on graph option.

The Select Statistic dialog opens.

2. Click a statistic to select it for the chart. Then, click OK.

Displaying statistics under a Process Capability Chart

You can select the statistics to display under a Process Capability chart.

To select the statistics that display:

1. Navigate to statistics under multiple capability chart = following this path on the Settings tab:

Chart overrides | Charts | Default reports | Statistics under multiple capability chart

2. Double-click Statistics under multiple capability chart.

The Statistics under multiple capability chart dialog opens. See Using Select Statistics dialogs

Note: To display statistics under a chart on your screen, the Show statistics list under chart option must be selected on the Settings tab.