Using Group Options
main topic      see also 

In the worksheet at right, the two grouping variables Style and Size each cycle through three values.

However, not all logical combinations are represented. The group Hooded/Large does not appear here. This combination is considered an "empty cell." Also, one row pairs a missing value in the column Style with "Small" in the Size column. This pairing is considered a "missing group."

Use the Group Options tab in Data Options to control how these items are graphed.

If you uncheck both Include missing as a group and Include empty cells, Minitab excludes the group Hooded/Large and the group created by a missing value and "Small."

You might exclude "empty cells" simply to save space on your graph, or to show that the group does not exist.

You might exclude "missing groups" if you do not want to graph items with indeterminate group values.

If you check only Include missing as a group, Minitab includes a bar for the "missing group" formed by an empty cell and the value "Small."

If you check only Include empty cells, Minitab includes an empty placeholder for the group Hooded/Large.

If you check both Include missing as a group and Include empty cells (the defaults), Minitab includes both empty cell and missing groups from the earlier examples, as well as the empty cells created by their combination (a missing value with "Medium" and a missing value with "Large"). When used in the context of paneling, these options have a similar effect on the number of panels created.