Balanced & Orthogonal Designs

Balanced and orthogonal designs are essential for producing clean, unbiased estimates in designed experiments. A balanced design ensures that each factor level appears the same number of times. An orthogonal design ensures that the effects of one factor are estimated independently of the effects of another. 

Balance and orthogonality are the backbone of clear interpretation. When a design is balanced, the estimates of factor effects are not influenced by unequal representation. When a design is orthogonal, the estimates of one effect are not distorted by correlations with other effects. 

In full factorial designs, balance and orthogonality occur naturally. In fractional factorial designs, they must be carefully preserved. Orthogonality ensures that main effects and interactions can be estimated cleanly, even when the design is reduced. 

In the Improve phase, balanced and orthogonal designs ensure that your experimental results are clear, interpretable, and actionable. They protect against bias, strengthen the validity of your conclusions, and support confident improvement decisions.