The Six Sigma Cheat Sheet
To apply Six Sigma to your business and produce the best results, you need to understand what
Six Sigma is, the principles of Six Sigma, and the DMAIC problem-solving method. The correct
tools and use of the Six Sigma scale and methods will keep your data dependable and reusable.
What Is Six Sigma?
Generally, Six Sigma is a problem-solving methodology that helps enhance business and
organizational operations. It can also be defined in a number of other ways:
A quality level of 3.4 defects per million opportunities
A rate of improvement of 70 percent or better
A data-driven, problem-solving methodology of Define-Measure-
Analyze-Improve-Control
An initiative taken on by organizations to create bottom-line
breakthrough change
Six Sigma Principles
Six Sigma is based on a handful of basic principles, and these principles create the entire Six
Sigma arrangement. Here are Six Sigma’s fundamental principles:
Y=f(X) + ε: All outcomes and results (the Y) are determined by inputs
(the X’s) with some degree of uncertainty (å).
To change or improve results (the Y), you have to focus on the inputs
(the X’s), modify them, and control them.
Variation is everywhere, and it degrades consistent, good performance.
Your job is to find it and minimize it!
Valid measurements and data are required foundations for consistent,
breakthrough improvement.
Only a critical few inputs have significant effect on the output.
Concentrate on the critical few.
Every decision and conclusion has risk (ε), which must be weighed
against the context of the decision.
The Six Sigma Scale
The Six Sigma scale shows how well a vital feature performs compared to its requirements. The
higher the sigma score, the more efficient the feature is. This table shows the universal Six
Sigma scale:
