Certified Six Sigma Black Belt Exam Certified Six Sigma Black Belt Measurement System Analysis (MSA) 1

Question 1

In Measurement System Analysis, what does 'bias' specifically refer to?

Accepted Answer

The difference between the observed average measurement and the accepted reference value

Answer

Bias (also called accuracy) is the systematic error component — it quantifies how far the average of repeated measurements deviates from the true or reference value. It is determined by comparing the mean of multiple readings on a reference standard to its known value.

Question 2

Which source of variation is captured by the ANOVA method in a Gage R&R study that the traditional Range (Average & Range) method cannot detect?

Accepted Answer

Appraiser-by-part interaction

Answer

The ANOVA method partitions variance into equipment variation, appraiser variation, AND the interaction between appraisers and parts. The Range method combines the interaction term into reproducibility and therefore cannot isolate it. Significant interaction means different appraisers are inconsistent specifically on certain parts.

Question 3

A Gage R&R study reports that the %Contribution of total Gage R&R to total variation is 6%. What does this value indicate about the measurement system?

Accepted Answer

The measurement system is acceptable because measurement error accounts for only 6% of total observed variance

Answer

%Contribution (variance-based) below 1% is ideal, and below 9% is generally considered acceptable per AIAG MSA guidelines. At 6%, the measurement system is acceptable — gauge error contributes very little to the observed variation, leaving the majority attributable to real part-to-part differences.

Question 4

In an Attribute Agreement Analysis, a Kappa value of 0.52 is calculated for an appraiser compared to the standard. How should this result be interpreted?

Accepted Answer

Moderate agreement — the system may require improvement before use in production

Answer

Kappa values are typically interpreted as: <0.40 = poor, 0.40–0.75 = moderate/fair, >0.75 = excellent. A Kappa of 0.52 falls in the moderate range, signaling that the attribute measurement system has meaningful disagreement with the standard and should be improved before relying on it for critical decisions.

Question 5

When is a nested (hierarchical) Gage R&R design required instead of a crossed Gage R&R design?

Accepted Answer

When the measurement process is destructive and the same part cannot be remeasured

Answer

A crossed design requires each appraiser to measure every part multiple times, which is impossible when measurement destroys the part (e.g., pull-strength testing, chemical titration). In a nested design, each appraiser measures a unique set of parts, so parts are 'nested' within appraisers, allowing repeatability and reproducibility to still be estimated.

Certified Six Sigma Black Belt Exam Practice Test

Certified Six Sigma Black Belt Exam Practice Test

Certified Six Sigma Black Belt Exam Certified Six Sigma Black Belt Measurement System Analysis (MSA) 1