Gatlin Education Six Sigma Green Belt - OVERVIEW Why Do Six Sigma - Page 2

What Is Six Sigma? We should begin with a brief explanation of the term Six Sigma. Sigma is the Greek letter used by statisticians to denote an estimate of variation called standard deviation. Sigma, or the standard deviation, can be calculated for any set of data, although its significance may be questionable based on the sampling techniques and analysis methods used. We can relate the calculated sigma to the customer requirements to determine a sigma level, as we will see shortly. When a process is at a Six Sigma level of performance, we are confident that there is only a very small chance for customer dissatisfaction. As we will soon see, improving a process to a Six Sigma level of performance is more of a journey than a task.