Control Chart Builder options appear in the red triangle menu or by rightclicking on a chart or axis. Some of the rightclick chart options also appear on the bottom left hand side of the chart for easy access. You can also set preferences for many of the options in the Control Chart Builder at File > Preferences > Platforms > Control Chart Builder.
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the Select Columns box

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Individual Points show or hides individual observations in a subgroup. Available only with a subgroup variable or Set Sample Size.

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Show Connect Line shows connecting lines between the points.

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Show Points shows or hides the points on the chart.

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Zones shows or hides the zones on the chart. The zones are defined as one, two, and three sigmas on either side of the mean. Control Chart Builder does not extend the size of one zone over another. If the limits are not centered around the mean, (UCLAvg)/3 is used as the width of each zone. Zones are not drawn below the LCL or above the UCL. Available only for Variables and Attribute chart types.

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Spec Limits shows or hides the specification limits on the chart.

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Set Control Limits enables you to enter control limits for tests.

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Add Limits specifies additional control limits to be plotted on the chart. These limits are not used in tests.

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Show Limits hides or shows the control limits on the chart.

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Show Center Line hides or shows the center line on the chart.

Adds a dispersion chart to the chart area. Change the chart type with the Points options. A dispersion chart illustrates the variation in the data by plotting one of many forms of dispersion, including the range, standard deviation, or moving range. Available only for Variables chart types.
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Customize Tests lets you design custom tests. After the option is selected, the Customize Tests window appears for designing the tests. Select a test description, and enter the desired number (n) and label. You can save the settings to preferences and also restore the default settings. Available only for Variables and Attribute chart types.

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Note: Move your cursor over a flagged point on the chart to see a description of the test that failed.
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Westgard Rules lets you select which Westgard statistical control tests to enable. Because Westgard rules are based on sigma and not the zones, they can be computed without regard to constant sample size. For more information about tests, see Westgard Rules. Available only for Variables and Attribute chart types.

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Test Beyond Limits enables the test for any points beyond the control limits. These points are identified on the chart. This test works on all charts with limits, regardless of the sample size being equal.

The Warnings option in the rightclick menu or on the left hand side of the window displays a submenu for Tests selection. You can select one or more tests for special causes (Nelson rules) from the menu. Nelson (1984) developed the numbering notation used to identify special tests on control charts. The tests work with both equal and unequal sample sizes.
Description and Interpretation of Special Causes Tests lists and interprets the eight tests, and Illustration of Special Causes Tests illustrates the tests. The following rules apply to each test:
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Detects a shift in the mean, an increase in the standard deviation, or a single aberration in the process. For interpreting Test 1, the Rchart can be used to rule out increases in variation.


Westgard rules are implemented under the Westgard Rules submenu of the Warnings option when you rightclick on a chart or on the left hand side of the window. The different tests are abbreviated with the decision rule for the particular test. For example, 1 2s refers to a test where one point is two standard deviations away from the mean.
Rule 1 2S is commonly used with LeveyJennings charts, where control limits are set 2 standard deviations away from the mean. The rule is triggered when any one point goes beyond these limits.


Rule 1 3S refers to a rule common to LeveyJennings charts where the control limits are set 3 standard deviations away from the mean. The rule is triggered when any one point goes beyond these limits.


Rule 2 2S is triggered when two consecutive control measurements are farther than two standard deviations from the mean.


Rule R 4S is triggered when one measurement is greater than two standard deviations from the mean and the previous measurement is greater than two standard deviations from the mean in the opposite direction such that the difference is greater than 4 standard deviations.


Rule 4 1S is triggered when four consecutive measurements are more than one standard deviation from the mean.


Rule 10 X is triggered when ten consecutive points are on one side of the mean.

For details about the Axis Settings, Revert Axis, Add or Remove Axis Label, and Edit options, see Using JMP.