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 fishbone diagram is constructed and most causes cluster under the 'Methods' category. What should the team do next?
Answer: Conduct a 5 Why analysis on the 'Methods' causes to find root causes
After identifying the dominant category, 5 Why analysis drills deeper into that category to identify actual root causes.
Which assumption must be verified before using a one-way ANOVA to compare means across three process lines?
Answer: Variances across groups must be approximately equal
One-way ANOVA assumes equal variances (homoscedasticity) across groups, which should be verified with Bartlett's or Levene's test.
A process improvement team creates a scatter plot and finds points forming a curved (non-linear) pattern. What is the BEST next step?
Answer: Apply a data transformation or fit a non-linear regression model
When a scatter plot shows a non-linear pattern, a data transformation (e.g., log, square root) or non-linear regression model is appropriate.
What is the primary purpose of a Failure Mode and Effects Analysis (FMEA) during the Analyze phase?
Answer: To prioritize potential failure modes by their Risk Priority Number (RPN)
FMEA identifies potential failure modes and scores them by RPN (Severity × Occurrence × Detection) to prioritize which risks to address.
When conducting a 5 Why analysis, a team arrives at the same root cause from two different symptom branches. This most likely means:
Answer: A single systemic root cause drives multiple symptom paths
Converging paths in a 5 Why analysis often signal a single, systemic root cause that produces multiple downstream symptoms.
A Green Belt wants to determine whether the median cycle time differs significantly across three suppliers. Normality testing shows non-normal data. Which test is most appropriate?
Answer: Kruskal-Wallis test
The Kruskal-Wallis test is the non-parametric alternative to one-way ANOVA used when data is non-normal and comparing medians across three or more groups.
In an Analyze phase tollgate review, which deliverable is MOST critical for demonstrating that root causes have been validated?
Answer: Statistical evidence linking X variables to Y outcomes
The Analyze phase must produce data-driven, statistical evidence that identified X variables are the verified root causes of Y performance problems.