CRE Quality Control Procedures 5

Question 1

What is the Consumer's Risk (Beta risk) in acceptance sampling?

Accepted Answer

The probability of accepting a lot at the Lot Tolerance Percent Defective (LTPD) quality level

Answer

Consumer's risk (β) is the probability that a bad lot at LTPD quality level will be accepted by the sampling plan.

Question 2

Which technique is used to quantitatively assess how much each factor and interaction contributes to variation in a DOE?

Accepted Answer

Analysis of Variance (ANOVA)

Answer

ANOVA partitions total variation into contributions from each factor and interaction, enabling statistical significance testing.

Question 3

A process produces 50 defects in 1,000 units inspected. What is the Defects Per Unit (DPU)?

Accepted Answer

0.05

Answer

DPU = total defects / total units = 50 / 1,000 = 0.05 defects per unit.

Question 4

What distinguishes 'tightened inspection' from 'normal inspection' in ANSI/ASQ Z1.4?

Accepted Answer

Tightened inspection uses a smaller acceptance number for the same sample size, applied after poor lot quality history

Answer

Under tightened inspection, the acceptance number is reduced (stricter), triggered when two of five consecutive lots are rejected under normal inspection.

Question 5

In measurement system analysis, what does 'bias' refer to?

Accepted Answer

The systematic difference between the observed average measurement and the reference (true) value

Answer

Bias (accuracy) is the offset of the measurement system's average from the true reference value, indicating systematic error.

(CRE) Certified Reliability Engineer Practice Test

(CRE) Certified Reliability Engineer Practice Test

CRE Quality Control Procedures 5