Resolution

An experimental design of resolution R is one in which no l-way interactions are confounded with any other interaction of order less than R - I. For example, in a design of resolution R equal to 5, no l = 2-way interactions are confounded with any other interaction of order less than R - l = 3, so main effects are unconfounded with each other, main effects are unconfounded with 2-way interactions, and 2-way interactions are unconfounded with each other.

For discussions of the role of resolution in experimental design, see 2(k-p) Fractional Factorial Designs and Searching for the Best 2(k-p) Fractional Factorial Design.