Pareto Chart of the Effects
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Use a Pareto chart of the effects to determine the magnitude and the importance of an effect. The chart displays the absolute value of the effects and draws a reference line on the chart. Any effect that extends past this reference line is statistically significant.

The method Minitab uses depends on whether an error term exists:

·    If no error term exists, Minitab uses Lenth's method [5] to draw the line and displays the unstandardized effects.

·    If an error term exists, Minitab uses the corresponding p-value that is shown in the Session window to identify important effects and displays the standardized effects. The reference line corresponds to a = 0.05, by default. You can change the a-level by changing the confidence level in the Options subdialog box or by setting a in the Stepwise subdialog box.

This plot shows that terms A, B, and AB are significant.