Lean Six Sigma Yellow Belt Certification Statistical Thinking and Variation 3

Question 1

What does DPMO stand for in Six Sigma quality measurement?

Accepted Answer

Defects per Million Opportunities

Answer

DPMO (Defects per Million Opportunities) is the standard Six Sigma metric for measuring quality, normalizing defect counts so processes of different scales can be compared.

Question 2

A process operating at Six Sigma quality produces approximately how many defects per million opportunities?

Accepted Answer

3.4 defects per million opportunities

Answer

Six Sigma quality is defined as approximately 3.4 DPMO, accounting for a 1.5-sigma long-term shift in the process mean from the centered target.

Question 3

The 'sigma level' of a process measures:

Accepted Answer

How many standard deviations fit between the process mean and the nearest specification limit

Answer

The sigma level indicates how capable a process is by measuring how many standard deviations fit between the process mean and the nearest specification limit — higher is better.

Question 4

Overadjusting a stable process that exhibits only common cause variation will:

Accepted Answer

Increase variation and worsen process performance

Answer

Tampering with a stable process — reacting to common cause variation as if it were a special cause — actually adds variation and worsens performance, a phenomenon Deming called 'tampering.'

Question 5

Process capability analysis compares:

Accepted Answer

The natural process spread to the customer specification width

Answer

Process capability compares the natural variation of the process (spread) to the customer's specification range to determine whether the process can reliably meet requirements.

Lean Six Sigma Yellow Belt Certification Practice Test

Lean Six Sigma Yellow Belt Certification Practice Test

Lean Six Sigma Yellow Belt Certification Statistical Thinking and Variation 3