Design Types

The following design types are supported in DOE++. For standard design folios, all six types are available. For robust design folios, only the factorial designs are applicable.

Factorial Designs: For screening vital factors

Two Level Factorial: Each factor must have exactly two levels. This design type can be used to investigate all main effects and their interactions (full factorial) or just a subset of them (fractional factorial).

Placket-Burman Factorial: This is a special category of two level fractional factorial design, where only a few specifically chosen runs are performed to investigate the main effects (i.e., no interactions).

General Full Factorial: Different factors can have different numbers of levels. All effects and their interactions are investigated.

Taguchi Orthogonal Array (OA) Factorial: This is a highly fractional design type. It can investigate main effects with just a few runs, and different factors can have different numbers of levels.

Central Composite Design Response Surface Method: This is the most commonly used response surface methodology design. It is typically used to study the quadratic effects of factors.

Box-Behnken Response Surface Method: This design type allows you to consider from three to nine quantitative factors at three levels each (one level being a center point). If setting all factors at the high level at the same time carries a risk of equipment damage or violates other constraints, these designs provide a matrix that avoids setting all factors at extreme values simultaneously.

Only one factor is investigated, and the response is compared at different factor levels. The factor levels must be qualitative. (To perform one factor analysis with quantitative levels, use the Multiple Linear Regression folio.)

What's Changed? Although some of the options from the Design Wizard in DOE++ 1 are no longer identified as separate "Design Types" in the current version, the functionality is still supported. Specifically:

Two Level Full Factorial or Two Level Fractional Factorial: Select a Two Level Factorial design and specify a value in the Fraction field after clicking the Additional Settings heading (i.e., "Full" for full factorial or a fraction for fractional factorial). (See Two Level Factorial Designs.)
Taguchi Robust Design: Create a robust design folio, which allows you to select separate design types for the inner and outer arrays of the design. (See Robust Parameter Designs.)
Reliability DOE: Select any design type in a standard design folio and set the Response Type for one of the responses to Life Data. (See Reliability DOE.)