Measurement System Analysis (MSA) Flashcards
7 cards from real Certified Six Sigma Black Belt Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Measurement System Analysis (MSA) flashcards as text
Which of the following is the correct interpretation when a Gauge R&R %GRR (based on study variation) is reported as 8%?
Answer: The gauge is acceptable for most applications
Per AIAG guidelines, a %GRR below 10% indicates an acceptable measurement system suitable for most applications.
What is the key difference between 'precision' and 'accuracy' in a measurement system?
Answer: Accuracy refers to closeness to the true value; precision refers to consistency of repeated measurements
Accuracy (low bias) means measurements are centered on the true value, while precision (low variation) means repeated measurements cluster tightly together regardless of where they center.
When should a Expanded Uncertainty be used instead of a simple %GRR in reporting measurement system performance?
Answer: When measurement results are used for legal, regulatory, or customer-contractual purposes
Expanded Uncertainty (per ISO/IEC 17025 or GUM) is required for calibration labs and situations where measurement results have legal, regulatory, or contractual significance.
A Gauge R&R study is run on a force-testing machine where each tested spring is permanently deformed after measurement. The appropriate study design is:
Answer: Nested (destructive) Gauge R&R design
Destructive tests require a nested Gauge R&R design because each part can only be measured once, so operators cannot all measure the identical same parts.
In MSA, 'effective resolution' differs from 'stated resolution' because it accounts for:
Answer: The actual measurement variation relative to the readable increment
Effective resolution considers whether the gauge's increments are fine enough relative to actual measurement variation to meaningfully distinguish different values.
Which statistical test is typically used to assess whether bias in a measurement system is statistically significant?
Answer: One-sample t-test comparing the mean measurement to the reference value
A one-sample t-test determines if the average measurement is statistically different from the known reference (true) value, indicating significant bias.
When analyzing a Gauge R&R using the ANOVA method, a p-value > 0.25 for the operator-by-part interaction term typically leads to:
Answer: Pooling the interaction into the repeatability (error) term
When the operator-by-part interaction is not statistically significant (p > 0.25 per AIAG guidance), it is pooled into the repeatability error term to produce a cleaner model.