Interaction diagram

Interaction diagrams only apply on DOE Full Factorial and Central Composite techniques.

It is used to determine if two factors (factor1 and factor2) interact with each other regarding a given response (response1).

It consists of two lines:

• The first line is the mean variation of response1 when factor1 varies from low level to high level and factor2 is at low level.

• The second line is the mean variation of response1 when factor1 varies from low level to high level if factor2 is at high level.

If factor2 has no interaction with factor1 then the mean variation when factor1 varies from high to low level does not depend on the value of factor2. Then the two lines are parallel as shown in the following figure.

Figure 102: No interaction between the two factors

If factor2 has interaction with factor1 then the mean variation when factor1 varies from high to low level depends on the value of factor2. Then the two lines are not parallel as shown in the following figure.

Figure 103: Interaction between the two factors

When Interaction diagram is selected, the dynamic part of the dialog box is as shown in the following figure.

Figure 104: Setup of an interaction diagram

Select the factors and the response you want to analyze using the drop-down lists and click on the OK button.

You must wait until the end of the design exploration process to create such a plot.

This type of plot cannot be updated.