By Craig Gygi, Bruce Williams, Neil DeCarlo, Stephen R. Covey

Part of Six Sigma For Dummies Cheat Sheet

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 (theY) are determined by inputs (theXs) with some degree of uncertainty (å).

  • To change or improve results (the Y), you have to focus on the inputs (theXs), 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.