Tip: When you have completed the Factors outline, consider selecting Save Factors from the red triangle menu. This option saves the factor names, roles, changes, and values in a data table that you can later reload in DOE platforms.
Figure 8.14 Factors Outline
The default values for a discrete numeric factor with k levels, where k > 2, are the integers 1, 2, ..., k. The default values for a discrete numeric factor with k = 2 levels are -1 and 1. Replace the default values with the settings that you plan to use in your experiment.
The default values for a categorical factor are L1, L2,..., Lk, where k is the number of levels that you specify. Replace the default values with level names that are relevant for your experiment.
Adds multiple factors. Enter the number of factors to add, click Add Factor, and then select the factor type. Repeat Add N Factors to add multiple factors of different types.
The name of the factor. When added, a factor is given a default name of X1, X2, and so on. To change this name, double-click it and enter the desired name.
The Design Role of the factor. The Design Role column property for the factor is saved to the data table. This property ensures that the factor type is modeled appropriately. The Role of the factor determines other factor properties that are saved to the data table. For details, see Factor Column Properties.
For each factor, various column properties are saved to the design table after you create the design by selecting Make Table in the Screening Design window. These properties are also saved automatically to the data table that is created when you select the Save Factors option. You can find details about these column properties and related examples in Column Properties.
If the Role is Continuous or Discrete Numeric, the Coding column property for the factor is saved. This property transforms the factor values so that the low and high values correspond to –1 and +1, respectively. For details, see Coding in Column Properties.
If the Role is Categorical or if a Block variable is constructed, the Value Ordering column property for the factor is saved. This property determines the order in which levels of the factor appear. For details, see Value Ordering in Column Properties.
Each factor is given the Design Role column property. The Role that you specify in defining the factor determines the value of its Design Role column property. When you select a design with a block, that Block factor is assigned the Blocking value. The Design Role property reflects how the factor is intended to be used in modeling the experimental data. Design Role values are used in the Augment Design platform. For details, see Design Role in Column Properties.
Each factor is assigned the Factor Changes column property with the value of Easy. The Factor Changes property reflects how the factor is used in modeling the experimental data. Factor Changes values are used in the Augment Design and Evaluate Design platforms. For details, see Factor Changes in Column Properties.