ICYB · Question #70
Six Sigma refers to a process whose output has at least 95% of its data points within 6 Standard Deviations from the Mean.
The correct answer is B. False. B (False) is correct because Six Sigma does not mean 95% of outputs fall within 6 standard deviations - it means the process achieves 99.99966% defect-free output, equating to only 3.4 defects per million opportunities. The "6 sigma" refers to having specification limits placed…
Question
Six Sigma refers to a process whose output has at least 95% of its data points within 6 Standard Deviations from the Mean.
Options
- ATrue
- BFalse
How the community answered
(45 responses)- A24% (11)
- B76% (34)
Explanation
B (False) is correct because Six Sigma does not mean 95% of outputs fall within 6 standard deviations - it means the process achieves 99.99966% defect-free output, equating to only 3.4 defects per million opportunities. The "6 sigma" refers to having specification limits placed 6 standard deviations from the process mean, making defects extraordinarily rare.
Why A is wrong: The 95% figure is a fundamental mischaracterization. In a normal distribution, 95% of data falls within ±2 standard deviations - that would be a 2-Sigma process, not Six Sigma. Claiming 95% for Six Sigma dramatically understates its quality standard.
Memory tip: Anchor on the number 2 for 95% (±2σ ≈ 95%). Six Sigma is far beyond that - think "6 sigma = near-perfect, 3.4 defects per million." If you remember that 2σ = 95%, you'll never confuse it with 6σ again.
Topics
Community Discussion
No community discussion yet for this question.