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Design and Analysis of Multi-Factored Experiments. Design Resolution. Design Resolution for Fractional Factorial Designs. The concept of design resolution is a useful way to catalog fractional factorial designs according to the alias patterns they produce.
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Design and Analysis of Multi-Factored Experiments Design Resolution DOE Course
Design Resolution for Fractional Factorial Designs • The concept of design resolution is a useful way to catalog fractional factorial designs according to the alias patterns they produce. • Designs of resolution III, IV, and V are particularly important. • The definitions of these terms and an example of each follow. DOE Course
1. Resolution III designs • These designs have no main effect aliased with any other main effects, but main effects are aliased with 2-factor interactions and some two-factor interactions may be aliased with each other. • The 23-1 design with I=ABC is a resolution III design or 2III3-1. • It is mainly used for screening. DOE Course
2. Resolution IV designs • These designs have no main effect aliased with any other main effect or two-factor interactions, but two-factor interactions are aliased with each other. • The 24-1 design with I=ABCD is a resolution IV design or 2IV4-1. • It is used mainly for screening. DOE Course
3. Resolution V designs • These designs have no main effect or two factor interaction aliased with any other main effect or two-factor interaction, but two-factor interactions are aliased with three-factor interactions. • A 25-1 design with I=ABCDE is a resolution V design or 2V5-1. • Resolution V or higher designs are commonly used in response surface methodology to limit the number of runs. DOE Course
Guide (continued) DOE Course
Guide (continued) • Resolution V and higher safe to use (main and two-factor interactions OK) • Resolution IV think carefully before proceeding (main OK, two factor interactions are aliased with other two factor interactions) • Resolution III Stop and reconsider (main effects aliased with two-factor interactions). • See design generators for selected designs in the attached table. DOE Course