Methods and formulas for the effects plots in Analyze Response Surface Design

Select the method or formula of your choice.

Pareto chart

Whether Minitab draws the plot depends on whether the model leaves degrees of freedom for error. If the model leaves 0 degrees of freedom for error, Minitab does not draw the plot.

The red line on the Pareto chart is drawn at t. This t is the (1 – α / 2) quantile of a t-distribution with the same degrees of freedom as the error term. Minitab labels this graph Pareto Chart of the standardized effects.

Normal Probability Plot

Whether Minitab draws the plot depends on the degrees of freedom for the error term. If the error term has 0 degrees of freedom, Minitab does not draw the plot.

Minitab plots the normal scores, probabilities, or percentages versus the standardized effects. The line corresponds to a normal distribution with a standard deviation of 1. Effects with p-values less than α are labeled significant on the graph. Minitab labels the graph Normal Plot of the Standardized Effects.

Half normal plot

Whether Minitab draws the plot depends on the degrees of freedom for the error term. If the error term has 0 degrees of freedom, Minitab does not draw the plot.

Minitab plots the normal scores, probabilities, or percentages versus the standardized effects. The line corresponds to a normal distribution with a standard deviation of 1. Effects with p-values less than α are labeled significant on the graph. Minitab labels this graph Half Normal Plot of the Standardized Effects.