Assessment Flashcards
7 cards from real Lean Six Sigma Black 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 Assessment flashcards as text
A Black Belt assessing a manufacturing process finds OEE of 48%. Which three OEE components multiply to produce this score?
Answer: Availability × Performance × Quality
OEE = Availability (planned uptime actually running) × Performance (actual vs. ideal speed) × Quality (good parts vs. total parts produced).
During process assessment a team finds that the measurement system's linearity is poor. What does poor linearity indicate?
Answer: The bias of the measurement system changes across the operating range
Linearity measures how consistent the bias is across the full range of expected measurements; poor linearity means the instrument's accuracy varies depending on where in the range you measure.
When assessing process stability using a control chart, which pattern suggests a special cause related to a gradual process drift or tool wear?
Answer: Six or more consecutive points trending in one direction
A sustained trend of six or more consecutive points moving in one direction is a Nelson/Western Electric rule that signals a gradual shift—often caused by wear, fatigue, or drift.
A Black Belt uses a cause-and-effect matrix (C&E matrix) to prioritize inputs for further data collection. The matrix scores each process input against:
Answer: Customer output requirements weighted by their importance rating
The C&E matrix scores each process input (X) for its impact on each customer-critical output (Y), weighted by the customer's importance rating for that output.
Which type of sampling is most appropriate when a process runs in natural groups (e.g., shifts, machines) and the Black Belt wants each group represented proportionally?
Answer: Stratified random sampling
Stratified random sampling divides the population into homogeneous subgroups (strata) and samples proportionally from each, ensuring all sources of variation are represented.
During baseline data collection, a Black Belt discovers the data contains outliers due to measurement errors. What is the appropriate action before computing capability metrics?
Answer: Investigate and document each outlier; remove only those confirmed to be measurement errors
Outliers should be individually investigated; only confirmed measurement or recording errors may be removed—legitimate process events must remain in the dataset.
A Black Belt calculates the Cost of Poor Quality (COPQ) for a process during assessment. Which of the following is a category of internal failure cost?
Answer: Scrap and rework before product reaches the customer
Internal failure costs are incurred when defects are found before the product reaches the customer; scrap and rework are the primary examples.