Capability Sixpack (Between/Within) - Tests
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Stat > Quality Tools > Capability Sixpack > Between/Within > Tests

Lets you select a subset of the eight tests for special causes. Each test detects a specific pattern in the data plotted on the chart. The occurrence of a pattern suggests a special cause for the variation, one that should be investigated.

You can set preferences for the tests to perform and for the sensitivity of these tests using Tools > Options > Control Charts and Quality Tools > Tests.

When a point fails a test, Minitab marks it with the test number on the plot. If a point fails more than one test, Minitab marks it by the lowest numbered test, and prints a summary table with complete information in the Session window.

Dialog box items

Tests For Special Causes (default definitions)

Perform all eight tests: Choose to perform all eight tests.

Choose specific tests to perform: Choose to specify a subset of the eight tests, then check any combination of the tests listed below.

One point more than 3 standard deviations from center line

Nine points in a row on same side of center line

Six points in a row, all increasing or all decreasing

Fourteen points in a row, alternating up and down

Two out of three points more than 2 standard deviations from center line (same side)

Four out of five points more than 1 standard deviation from center line (same side)

Fifteen points in a row within 1 standard deviation of center line (either side)

Eight points in a row more than 1 standard deviation from center line (either side)