Lean Six Sigma Black Belt Certification Lean Six Sigma Black Belt Improve Phase: DOE Questions and Answers 2 — Questions and Answers
Question 1: In a 2^k full factorial design, what does the 'k' represent?
- The number of factors being studied (Correct answer)
- The number of replicates per treatment
- The total number of experimental runs
- The number of response variables
Correct answer: The number of factors being studied
In a 2^k factorial design, k represents the number of factors, each tested at two levels.
Question 2: What is the primary purpose of randomization in a designed experiment?
- To reduce the effect of lurking variables and bias (Correct answer)
- To increase the number of experimental runs
- To ensure all factors are tested at the same levels
- To eliminate the need for replication
Correct answer: To reduce the effect of lurking variables and bias
Randomization helps minimize the impact of uncontrolled variables by distributing their effects evenly across treatments.
Question 3: A Black Belt runs a 2^4 full factorial experiment. How many unique treatment combinations exist without replication?
- 16 (Correct answer)
- 8
- 32
- 12
Correct answer: 16
A 2^4 design has 2×2×2×2 = 16 unique treatment combinations.
Question 4: What does a significant interaction effect in a DOE indicate?
- The effect of one factor depends on the level of another factor (Correct answer)
- Both factors have no individual effect on the response
- The experiment has too many factors to analyze
- Randomization was not properly applied
Correct answer: The effect of one factor depends on the level of another factor
A significant interaction means the combined effect of factors differs from the sum of their individual effects.
Question 5: Which resolution in a fractional factorial design allows estimation of all main effects but confounds them with two-factor interactions?
- Resolution III (Correct answer)
- Resolution IV
- Resolution V
- Resolution II
Correct answer: Resolution III
Resolution III designs confound main effects with two-factor interactions, making them suitable only when interactions are assumed negligible.
Question 6: What is the purpose of center points added to a 2-level factorial design?
- To detect curvature in the response surface (Correct answer)
- To increase the resolution of the design
- To replace the need for replication
- To reduce the total number of runs required
Correct answer: To detect curvature in the response surface
Center points allow the experimenter to test whether the relationship between factors and response is linear or curved.
Lean Six Sigma Black Belt Certification Lean Six Sigma Black Belt Improve Phase: DOE Questions and Answers 2
In a 2^k full factorial design, what does the 'k' represent?