Six Sigma Black Belt Flashcards

In the Measure phase of DMAIC, which metric represents the number of defects per million opportunities?

Answer: DPMO

DPMO (Defects Per Million Opportunities) is the standard metric used to quantify process defect rates in Six Sigma.

A process with a Cpk of 1.33 operates at approximately which sigma level?

Answer: 4 sigma

A Cpk of 1.33 corresponds to a 4-sigma process, yielding approximately 6,210 DPMO.

Which sampling method ensures every possible sample of a given size has an equal probability of selection?

Answer: Simple random sampling

Simple random sampling gives every possible sample of size n an equal chance of being chosen, minimizing selection bias.

In a cause-and-effect (Ishikawa) diagram for a manufacturing defect, which of the following is NOT a standard 'bone' category?

Answer: Market

The standard 6M categories are Man, Machine, Method, Material, Measurement, and Mother Nature (Environment) — Market is not one of them.

What does the term 'tollgate review' refer to in a Six Sigma project?

Answer: A formal phase-gate review where leadership approves advancement to the next DMAIC phase

Tollgate reviews are structured checkpoints at the end of each DMAIC phase where the team presents findings and obtains sponsor approval to proceed.

Which statistical tool is used to determine whether two or more population variances are equal?

Answer: Bartlett's or Levene's test

Bartlett's test (for normal data) and Levene's test (for non-normal data) are used to test equality of variances across groups.

In Design of Experiments (DOE), what is the purpose of 'blocking'?

Answer: To isolate and control the effect of a known nuisance variable

Blocking groups experimental units by a known nuisance factor so its effect can be separated from the treatment effects of interest.