Manufacturing and Production Six Sigma and Process Improvement 2 — Questions and Answers
Question 1: What is a regression analysis used for in Six Sigma?
- Scheduling maintenance tasks
- Identifying and quantifying the relationship between input variables and output outcomes (Correct answer)
- Mapping process value streams
- Auditing supplier performance
Correct answer: Identifying and quantifying the relationship between input variables and output outcomes
Regression analysis quantifies how changes in input variables (Xs) affect the output (Y) to guide targeted improvements.
Question 2: Design of Experiments (DOE) in Six Sigma is used to:
- Design facility floor plans
- Systematically test multiple input variable combinations to optimize process outputs (Correct answer)
- Draft engineering change orders
- Design employee training programs
Correct answer: Systematically test multiple input variable combinations to optimize process outputs
DOE efficiently tests multiple factors simultaneously to identify which variables most significantly affect the process output.
Question 3: What does DPMO stand for?
- Defects Per Machine Output
- Defects Per Million Opportunities (Correct answer)
- Daily Production Monitoring Operations
- Defined Process Measurement Objective
Correct answer: Defects Per Million Opportunities
DPMO normalizes defect rates to a per-million scale, enabling comparison across processes with different complexity levels.
Question 4: In the Control phase of DMAIC, which tool is most commonly used to sustain improvements?
- Fishbone diagram
- Control chart (SPC) (Correct answer)
- Pareto chart
- Scatter diagram
Correct answer: Control chart (SPC)
Statistical process control (SPC) charts are placed on the improved process in the Control phase to detect any drift back to old performance.
Question 5: What is a hypothesis test used for in Six Sigma projects?
- Writing project charters
- Statistically determining whether observed differences between groups are real or due to chance (Correct answer)
- Creating control plans
- Setting machine parameters
Correct answer: Statistically determining whether observed differences between groups are real or due to chance
Hypothesis tests (like t-tests, ANOVA) validate whether process changes or differences are statistically significant.
Question 6: What is a 'tollgate review' in a Six Sigma project?
- A final inspection of finished goods
- A structured phase-end review where the project team presents findings to leadership before proceeding (Correct answer)
- A machine calibration checkpoint
- A supplier quality audit milestone
Correct answer: A structured phase-end review where the project team presents findings to leadership before proceeding
Tollgate reviews ensure each DMAIC phase is properly completed and results validated before the team advances to the next phase.
Manufacturing and Production Six Sigma and Process Improvement 2
What is a regression analysis used for in Six Sigma?