What exactly is sigma performance?
Sigma performance measures process performance relative to customer requirements. It takes into account some degree of undetected, nonrandom variation (“shift”). Unlike the capability index, all qualities, both measurable and countable, can be combined into a single scorecard. Sigma can be normed to the complexity of the process using defects per million opportunities (DPMO) to facilitate comparisons across different processes. What is the goal of Six Sigma The goal is for an organization to achieve strength by moving progressively toward a sigma performance level of 6. At this level, the process is robust against undetected process shifts; that is, variation is small enough relative to the requirements that a shift will not result in more than a few defects in a million opportunities. Doesn’t “sigma” referred to the standard deviation of data. It does, and for measurable data, sigma performance is directly related to the standard deviation. The two uses of the term “sigma” should not,
