DMAIC: Analyze Phase Techniques Flashcards
7 cards from real Lean Six Sigma Green Belt Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 DMAIC: Analyze Phase Techniques flashcards as text
A process improvement team wants to test whether the proportion of defective units differs between two production lines. Which test is most appropriate?
Answer: Two-proportion z-test
The two-proportion z-test compares proportions (attribute data) from two independent groups to determine if they are statistically different.
When a team performs regression analysis and finds that adding a second X variable increases R² from 0.72 to 0.73, the BEST interpretation is:
Answer: The second variable adds minimal explanatory value and may not justify model complexity
A marginal R² increase suggests the second variable contributes little additional explanatory power while adding model complexity, so its inclusion should be questioned.
In a Lean Six Sigma Analyze phase, what is the purpose of calculating takt time?
Answer: To set the pace of production required to meet customer demand
Takt time is calculated as available production time divided by customer demand, setting the required production pace to meet demand without overproduction.
A team uses an affinity diagram during the Analyze phase. What is the PRIMARY output of this tool?
Answer: Ideas or data grouped into meaningful themes based on natural relationships
An affinity diagram organizes large amounts of qualitative data (ideas, observations) into related groups or themes through collaborative sorting.
Which type of error occurs when a team concludes that a root cause IS significant when it actually has no real effect on the output?
Answer: Type I error (Alpha error)
A Type I error (false positive) occurs when the null hypothesis is incorrectly rejected, concluding a significant effect exists when it does not.
A Green Belt discovers through data analysis that the process mean has shifted over time but process spread remains constant. Which graphical tool would BEST confirm this finding?
Answer: I-MR chart showing a sustained shift in the individual values
An I-MR (Individuals and Moving Range) control chart reveals a sustained shift in the process mean while the Moving Range chart confirms spread is stable.
A team identifies three potential root causes through analysis. Before moving to Improve, what is the MOST important validation step?
Answer: Conduct designed experiments or additional data analysis to confirm each cause's impact
Root causes must be statistically confirmed through data analysis or controlled experiments before moving to Improve, ensuring resources are directed at true causes.