Statistics for Six Sigma Made Easy

1.4. WHAT WE HAVE LEARNED IN CHAPTER 1

1. The Six Sigma methodology uses a specific problem-solving approach and select Six Sigma tools to improve processes and products.

2. People with expertise in Six Sigma are called green belts, black belts, or master black belts.

3. The name Six Sigma came from the goal of reducing defects to 3 parts per million, which is ±6-sigma (including some process drift).

4. Most companies produce at an average ±3-sigma quality level (99.73% good product), which generates 2700 defects per million parts. For most real-world situations, this is a level of defects that is excessively high, but the optimum quality level is usually not as tight as ±6 sigma. A realistic goal is to make a product that satisfies the customer and minimizes ...